Valve adjustment on 82 r100rt gone wrong

[asaint]

Hi all,

I read through the Clymer procedure on performing valve adjustment this morning and thought it looked straight forward. Encouraged by a neighbor (who is an old auto mechanic) who walked into my garage, I decided to give the procedure a try.

Things didn't go well. Here is what I did;

1. Put the bike up on a block of wood and shifted into 5th
2. Removed both head covers
3. Removed both spark plugs
4. Rotated the back tire until the following appeared in the timing hold

OT
S

5. Using a feeler gauge, set gap to .10mm Intake, .20 mm exhaust
*note - the rocker arm has a little "rocker play" in it after tightening the outer nut
6. Rotated the tire and repeated on other head

Started the bike and it felt/sounded like my washing machine. Vibrations and what sounded like pinging or metal hitting.

I took a deep breath, and repeated the procedure. Same results.

Ok, what did I do wrong here?

peace,
Asaint

[20774]

You need to set the valves on the cylinder that is at TDC of the "compression" stroke. If you have the plugs out, put your thumb over the spark plug hole and rotate the tire. As soon as you begin to feel pressure on your thumb, begin to look for OT in the window. Stop...set the valves on that side.

Repeat for the other side. When you're at TDC on the compression stroke, be sure that both pushrods can be spun by your fingers. They should once the clearances are set right.

You don't necessarily need to remove the plugs, but it does make it easier to turn the engine. Otherwise, just watch the intake valve on, say, the left cylinder. As soon as you see it open and then begin to close, you're beginning the compression stroke. Slowly continue engine rotation until you see OT...set the valves. Again, repeat for the other side. Or, if you've set the left side, then rotate the engine one complete revolution and you should be at TDC on the right side.

[asaint]

20774,

Ok, I just followed your procedure and the bike is almost normal. However, I now have "tapping" sounds coming from each head. I just idled it and havn't taken it for a ride.

Is this tapping normal? um.. how can I make it go way??

Just so I'm double-triple sure I did this right, here is what I did.

1. I watched the intake valve on left side. Once the intake valve started to move IN, I turned the wheel forward/backwards until the OT:s mark appeared in the hole

2. I adjusted the valves

3. I turned the wheel 2 full rotations

4. Repeated the above on the right side

Is it safe to ride?

peace,
Asaint

[20774]

I don't know about the 2 full wheel revolutions...it depends on the final drive, gear your in, etc...I don't really want to do the math. Either watch the other side intake valve or carefully watch the timing marks until you see the next OT in the window. That should be the proper position to set the valves on the opposite side.

Another thing...once you saw the intake move IN, you want to keep moving the tire rotation forward...try not to go backward. I sit beside the bike with a flashlight shining in the timing hole. When I start to get close, I use my hand and grab the spokes and easily bounce the wheel so that the engine moves a little at a time. Once I see the F mark, then the S mark, then I start to be more careful with the bounces so I creep up on the OT mark. Probably OK for slight back and forth at this point, but try to just keep moving the flywheel in one direction.

Tapping valves? Well, they say "a tapping valve is a happy valve". There will be some tapping noises once set correctly.

One thing you may be experiencing is the whole rocker arm moving up and down too much. When you've set the clearances for a given side, try to move the rocker arm up and down. You should only see an oil film movement where the rocker arm meets the pillow blocks. If you see any substantial movement, then you have too much movement and this will create extra noise.

The '82 rocker arms are indexed better than the previous versions in the mid '70s. But there can still be some adjustments to minimize this up-down movement. This can be done by squeezing the pillow blocks together while the head bolts are torqued. Duane Ausherman shows this on his website:

http://w6rec.com/duane/bmw/valve/index.htm

Taking a step back, one of things you should be sure of is the torque of the head bolts. This should be done on a cold engine prior to setting the valve clearances. Using a proper technique, a good calibrated torque wrench, the head bolts should be torqued up to about 25 ft-lbs. While doing this, the pillow blocks can be squeezed together to minimize the up and down movement of the rocker arms.

[asaint]

Ok,

I shot a 1 minute video and you can hear my tapping valves. Take a gander and let me know if this is a problem

http://www.youtube.com/watch?v=BgkKUIN0Npo

[20774]

From the sounds of it, something's not right...that's too much noise. I wouldn't ride it until I figured out what's wrong. Sorry to say, but I think you need to go back over the process.

You said you set the valves at 0.10 and 0.20mm. You didn't by any chance go with 10 and 20 "thousandths" did you? That would be fairly huge for a gap...

[asaint]

20774,

The feeler gauge has both MM and Inches. I used the MMs.

Thanks for the Snowbum link. I read over his valve article. One piece of the procedure that caught my eye is his instruction to push down on the rocker end of the arm while performing the gap measurement. I can't remember if I did this.

I'll perform the procedure for the (gulp) 4th time tomorrow and push down on the rocker arm while gapping. See if that makes a difference. I'll also take some still photos of what I'm doing and post a couple. Maybe I'm overlooking something obvious.

peace,
Asaint

[20774]

I reread your first couple of posts. You said twice that you put the OT:S mark in the window. You shouldn't see the S mark, just the OT mark. If the S mark is visible as well, you won't be at true top dead center and if you set the valves at that point, you'll have "extra" clearance which could be the extra noise you're hearing.

[Bill Burke]

You know who's "a saint"? It's kurt for trying to explain this in writing. I agree that the video indicates valves that are making too much of a racket. You don't happen to know any other airheads do you? How about an airhead shop? The valve adjust procedure is a practiced art which can indeed be reduced to a matter of minutes but it can be handy to have an experienced teacher for the first effort. This is one of the best things you can learn to do with your airhead. Hang in there.

[asaint]

Bill,

I very much advice and tips Kurt is giving me. Hopefully someday I can return the favor somehow.

I tried to join my local BMW club but I never received an acceptance to join their Yahoo group (their only contact). Next step is for me to join the Chicago BMW group. That group meets about an hour from me. Not too bad a trip but I was hoping for something closer.

I'm happy to give the procedure another go. Might try it this time without removing the spark plugs (ala snowbum).

I'm hanging in there!

peace,
asaint

[Bill Burke]

Good. It's well worth the effort. Your machine's idling and overall performance is heavily dependent upon well-adjusted valves. Oddly enough, really quiet valves are a sign that they've closed up (and in time will overheat). Airhead valves are supposed to make a pleasing sewing machine racket, but not a real clatter. Keep pulling the plugs to do this exercise....especially if you're working alone. Trying to turn the engine over with the plugs in is asking for an early trip to the back surgeon to fuse a few discs.

[asaint]

Bill,

You're not kidding about taking the plugs out. I went out and did the valve procedure (4th time - I hear I get a tee-shirt if I make it to 6), and tried to move the wheel with the plugs in. No way brother - Snowbum must be power lifter or something. I pulled the plugs....

I was meticulous in setting the valve gap and carefully tightening the lock bolt on each rocker arm. Bike isn't any better.

For no particular reason, here's a picture of my right cylinder's valves.

[20774]

I don't remove the plugs unless I really need to...one less thing to cross-thread!!

Yes, it's hard to turn the engine over with the rear wheel but you're just fighting the compression (that's good!) and all you have to do is let it bleed a bit as you move through the stroke. Plus there's one spot in the rotation where it becomes the hardest due to the geometry of the rod, crank, etc.

I'd still like to hear about what mark you're seeing in the timing window....it should just be the OT...the S mark should not be visible.

I don't see anything unusual with the photo. It appears that you have a reasonable number of exposed threads on the rocker arm adjusters.

Another thing you might try is confirming that OT is truely top dead center. They make a screw-in device for this, but it can be done without it. With the plugs out, and the piston nearing top dead center, put something into the plug hole like a pencil or something that won't harm the metal. You also don't want this to break or drop inside the cylinder. Continue to turn the rear wheel as you hold the pencil as it pushes out of the hole. At some point it will stop moving out. Later it will begin to move inward as you go past TDC. Play with these two points and try and estimate the midway point between them. That should be where OT is in the middle of the window.

There is a band over which the piston is all the way out and the cam lobe that is moving the rocker arm is pushing all the way out. The valves can really be set anywhere within this band.

But I don't believe the S mark should be visible in this process when setting the valves.

[sumran]

When you have the clearance adjusted on the first set of valves, rotate the push rods with your fingers. They will spin freely. When you come to the OT mark again, try to spin the pushrods on the side you just adjusted. If you can spin them, you have gone around twice (easy to do) and the second side is in the wrong position for adjustment. Adjusting the second side in that position would lead to noises like what you described.

[asaint]

20774,

Find attached a very blurry image of the

OT
S

I am seeing through the hole. The little "card" comes around and the OT is stamped directly above the S. From what I remember, there appears to be 2 of these. In between is another "card" with a Z.

Now for the pencil trick. What I want to do is hold a pencil in place and when it is pushed out fully and about to descend back in, this is top dead center?

peace,
Asaint

[asaint]

Sumran,

Ok, that sounds easy enough to try. Let me list this to insure I have it right;

1. Adjust left valves
2. Spin the rods (will spin freely)
3. Move the rear tire, align OT with intake valve just about to descend on right side
4. Attempt to spin left side rods - if they spin freely, <gong> wrong mark

Is this right?

asaint

[20774]

asaint -

From the picture, it appears that the S mark is in the middle of the timing window...it might just be the parallax of the shot. There should be a cutout in the round window, a nick on the left side IIRC. This nick and the line associated with OT should line up. Don't use the letters "OT" but rather the line associated with it or maybe there's a dot. It's the mark, not the letters.

As for the pencil trick, yes, just hold the pencil so it can move freely while you rotate the engine such that the pistion moves out fully and then begins to move back towards the crank. Somewhere in between when the piston stops moving and starts moving should be OT.

[asaint]

Kurt,

Wow! I just ran out to the bike and see there is a nick on the middle left center of the hole.

I have not been aligning the nick with the line below the OT. I just got the "OT" in the middle of the window and began my adjustments.

I'll have to get down pretty low to line those 2 up. Not to mention the wheel is a bit of a bear to spin for small adjustments.

Thanks!
Asaint

[manicmechanic]

Disconnect the ground wire from the battery. Remove the front cover from the engine. Remove the spark plugs. Use a larger allen wrench(6mm, I believe) to rotate the alternator bolt which rotates the engine. Watch the valves. When the intake valve opens, then closes, look for the OT mark on the flywheel. The side on which the intake valve just closed is at TDC on compression. Adjust the valves as needed on that cylinder. Then rotate the engine one complete revolution and adjust the valves on the other cylinder. Replace the front cover and restore the rest of the parts that were removed. Start the bike and see if it isn't quieter. Proper clearance is .006" intake and .008" exhaust.

[sumran]

Sumran,

Ok, that sounds easy enough to try. Let me list this to insure I have it right;

1. Adjust left valves
2. Spin the rods (will spin freely)
3. Move the rear tire, align OT with intake valve just about to descend on right side
4. Attempt to spin left side rods - if they spin freely, <gong> wrong mark

Is this right?

asaint

Correct. It wouldn't mean you had the wrong mark; it would mean you missed it the first time it came around.

[AnnapolisAirhead]

I think Randy and Kurt nailed it. Here' is your picture and the blue line where the OT mark should be sitting. Currently, you are splitting the "OT" and the "S" mark.

I do the same trick with the pushrod tubes and watching the compression stroke. When I see the "Z" mark ("F" on older airheads), I start watching for the "S" mark. When that appears, I go very slowly until the "OT" mark is centered on the little nick in the timing hole (at 9:00 if you are looking at the timing hole as a clock). Then, I try to twist the pushrod tubes--the tubes will only be able to be twisted on one side and that's the side you set the valves on. After setting them, start to turn the rear wheel again until you see the "Z" or "F" mark, then look for "S". go slowly until "OT" is centered again--then set the valves on the other side.

For simplicity sake, I set the left side valves first.

That YouTube video was a good way to share the sound--it needs to be fixed before you ride. Nice job.

[mmmalmberg]

I could be crazy but I never thought it critical to be right on the OT mark. The cams are in a constant radius during TDC, aren't they?

With plugs in, use 5th gear to turn the rear wheel, much easier...

[20774]

We'll see...from what I can tell, the OP might have been 3-4 degrees away from TDC. Seems like that could make a difference. I've never tried it anywhere but exactly at the OT mark, so I wouldn't know the amount of distance you could go either way and still get a good valve setting.

[asaint]

alright guys,

I just completed my 5th attempt at valve clearance. No it didn't work, but 2 observations;

1. The difference in the valve clearance between when the line above the OT mark is aligned with internal nick and when it is at the bottom of the window DOES make a difference.

2. I guess I don't understand what is being meant by "spin the push rods". Let's take a peek at the photo below as a guide to my newebness to all this.

What I understand to be the "push rods" are the rods that extend into the cylinder behind the 2nd adjustment nuts. The red arrows point to these. What I did was attempt to spin these. Problem is they ALWAYS spun when the OT was aligned and the internal valve starts to descend. I would rotate the wheel, align and the rods would spin. They always seem to spin

What am I doing wrong?

BTW - anyone out in the Elgin area of Chicago reading this and wants to look over my shoulder, let me know.

peace,
asaint

[AnnapolisAirhead]

Asaint, I think you are doing it right. The side that is at TDC and you are about to adjust, you SHOULD be able the spin/twist between your fingers. So, if you are about to adjust the valves on the left side, those pushrods should be 'spinnable' and the right side pushrods should not.

Make sense?

I'm about to set my valves in a few minutes (after 500 miles on new valves) and I'll try to take a few picture. I'll also PM you my phone number if you want to call.

[20774]

Problem is they ALWAYS spun when the OT was aligned and the internal valve starts to descend. I would rotate the wheel, align and the rods would spin. They always seem to spin

They always seem to spin?? Now that's not right. At some point in the rotation of the rear tire, away from OT, the pushrod tubes (and you were correct in where they are) should NOT spin. Only when you are at top dead center on the compression stroke for one cylinder will they spin under the proper amount of valve clearances. For most if not all of the remainder of the flywheel movement, the rods will be under some compression. I could be wrong there...for instance, what is the situation with the intake pushrod when the exhaust valve is being compressed. Normally, the intake valve will be closed which might mean there's no compression on the rod and it could spin. I've never checked that before...I'd have to think about that.

But I find it odd that you intimate that the pushrods could be spun ALL the time.

And when you're setting the clearances when the cylinder is positioned properly, you pushing back on the adjuster nut and pulling the feeler gage between the valve stem and the tappet extension on the rocker arm such that there is a slight drag on the feeler gage? The place that you're testing the clearance is at the "working end" of the valve just the the work "2nd" in your previous photograph?

I'm beginning to wonder about collapsed pushrods, the wrong type of pushrods, cam lobes worn down, failed bearings in the rocker arms, head bolt torque, etc.

I wish I was closer I'd come help...here's a video I found on youtube:

- basic valve operation -- http://www.youtube.com/watch?v=2afi8wKr2_Q

I thought I might be able to find someone actually setting the valves, but I didn't find anything...

[asaint]

Annapolis,

Yes it makes sense and I did it right. Now, why the heck are the valves still tapping away with hammers?

I appreciate the photos and the phone #. I'll give this another go tomorrow if I see something in your photos I did wrong.

Oh, after doing this 5 times it finally dawned on me to check the oil level. Each head dumps a glob onto my rags when I remove the cover.

I also have the battery on a smart charger. I've been doing the valves, starting it, etc, etc.

peace,
asaint

[asaint]

Kurt,

I mis-phrased that piece about always spinning. I blame my fingers that are covered in engine oil and both knuckles skinned from loosening nuts and banging them on some bolts. Funny - but I'm quite happy at the moment.

Yes, when at OT, the rods always spin. For some reason I got it into my head that the cylinder could be at OT but the rods not spin (makes no sense now that I type it out).

Bingo on where I'm using the feeler gauge. At the end of the rocker arm and the top of the valve. I have the feeler gauge in one hand while the other adjusts the 2nd nut. Once it feels right, I drop the feeler gauge, pick up the 2nd wrench and tighten the first nut.

Dunno if this has anything to do with anything but the top end was done back at 110,000 miles by the PO. I'm currently at 122,000.

peace,
Asaint

[AnnapolisAirhead]

Oh, after doing this 5 times it finally dawned on me to check the oil level. Each head dumps a glob onto my rags when I remove the cover.

Psst, that's a good thing. Oil travels along the top two studs to lube the valve train. You want that oil in there.

If you wipe the oil off your skinned hands and the pushrods, are you saying that at OT both sides can spin? Only one side or the other should be able to spin. Not both.

Also, when you tighten the valves (with two wrenches, right?), it can be tricky as even the slightest movement of the inboard nut you are holding can change the clearance you have so carefully set. So, check them again AFTER you've tightened the nuts. You may find that they have changed. I'm be no means a guru at this, but I try to get it set so that I can feel friction on the feeling gauge but not so much that any serious tugging is required to remove it. When in doubt, I leave it too loose rather than too tight.

[skiteach]

Most tool dealers, Snap On & Mac come to mind have "go, nogo" feeler gauges. They have a step milled into them. The drag should be like a hot knife thru butter. Adjusting Porsche valves, it's really handi to have these types of gauges and for the rest of us that do not do it as part of daily routine. I've also never trusted the spin the push rod method. Rather, rock(turn) the engine back and forth, if the valves move-Wrong time to adjust, rotate again. Removing spark plugs is easy and makes the engine turning much easier

[asaint]

Annapolis,

The rods only spin on one side when the OT sign is aligned in the window.

I've found out the hard way how delicate the final setting is on the 2 nuts to adjust the valves. Even putting the 2nd wrench on offsets the valve clearance enough so you have to re-adjust.

Funny, the intake valves are more difficult to set then the exhaust (not withstanding the increased clearance on the exhaust valves). I find it super easy to have too little clearance set on the intakes. For some reason just tightening the outside nut pushes the valve closed too far.

go-nogo feeler gauges? hmmm... sounds expensive - how much are they?

peace,
Asaint

[skiteach]

go-nogo feeler gauges? hmmm... sounds expensive - how much are they?

Probably not very much more than regular-mine are at least 20 yrs old-don't remember. Should be able to find them online, or a tool dealer.

[seniorasi]

A few questions: Did the engine rattle before the first valve adjustment attempt? Did you measure the valve clearance before you re-set the clearance? If the answer to these questions is no my suggestion is to check for bent push rods by removing and rolling them on a flat surface. It might help to read through the procedure in the Clymer manual as well.

[asaint]

Seniorasi,

Well.. I didn't measure the clearance before the 1st attempt. Did they rattle before? I purchased the bike about 6 weeks ago, it always sounded a bit loud. However, I didn't even know what a valve was back then and wasn't listening for taps in the heads.

Interesting idea to take the rods out and see if they are bent. I'll read up on that procedure tomorrow. Can't hurt to give it a try.

peace,
asaint

[skiteach]

Asaint, Snap On web site shows 22 blade step feeler gauge set for $13.90, part # FB322. Looks like you can now order online, glad you couldn't do that when I worked for them!

[sumran]

Checking for bent pushrods is worthwhile, but understand that you will need to be careful about torque on the head bolts during removal and reinstallation. You will get various opinions about whether you can leave the bolts at 12 o'clock and 6 o'clock in place while you check the rods.

Besides needing to torque in the cylinder studs you would also need to set rocker clearance, which could provide another source of noise.

You may need to check the pushrods, but you are getting a lot of things that are new to you on the table at once.

[AnnapolisAirhead]

I just had a sobering thought. When you are setting the valves, are you 100% certain that the pushrod is in the valve socket before you set and tighten them? It does sound too noisy in the video. If you ever loosened the nut enough, the pushrod can actually slip out of that little socket on the backside of the rocker arm. If that were the case the first time you fired it up to listen...it may have/probably would have bent the pushrod. Hopefully that's not the case.

+1 on Randy's last post.

Snap-On sells online...eeegads, who'd a thunk that day would come? :dunno

[paulfinney2]

In order to keep the valve adjustment from changing when tightening the lock nut, I use a small needle nose vise grip. I clamp it on the adjuster nut [closer to the engine] , loosen the lock nut, set the gap with the feeler guage by moving the vise grip, then hold the vice grip without moving it, while I tighten the lock nut. Then re-measure the gap. And repeat as necessary.

[FLbmw]

Reading these posts makes me wonder. After all these adjustments, then running the bike, then re-adjustment, time after time. Are you adjusting the valves with the bike totally cooled down. You have to adjust with the bike cool. A warm engine expands and will not get an accurate setting.

[26667]

asaint, if you have trouble hooking up w the Chi Reg club for a tech day, get in touch w me after the fourth of july(sorry but I'm vacationing till then), maybe we can get together at my garage or yours and I'll go thru it w you face to face. Having my guru walk me thru the process was an enormous help to a formerly-wrench-challenged guy such as myself. Once you've got it you'll be a very happy camper. I don't think it'll matter much if we do my bike or yours, just so we walk you thru the process, but it'll need to be the cold one. then we can have a cold one.

Be sure and join Airheads or at least go to the ABC website calendar and see if there's a tech-day that you can get to. Aside from meeting all the crazies...I mean nice people who will show you all there is and a little more, you'll have some fun, too. Keep an eye out for saturday tech sessions at Johnny's place...Motoworks at 19th and Western. They have a site too, but I'm not sure how regularly it's updated.

Wish I could get out there and help, but we're off to the airport.

[asaint]

26667,

Happy vacation. I appreciate the offer and if I still have a problem by the 4th, I'll give you a holler.

I applied online yesterday for the Airheads club. I haven't received my membership yet. Once I do, I'll poke around over there and see how to get hooked into the local club stuff. Looking forward to it.

peace,
Asaint

[asaint]

Randy,

I haven't read the procedure on how to remove the pushrods, but your comments give me pause. Upon reflection perhaps I'll wait on removing the pushrods until all other options have been explored and exhausted. Might be worthwhile to wait until I have someone standing next to me who can guide me through it.

peace,
Asaint

[asaint]

Annapolis,

Great thought and one that never occurred to me. After work I'll take the head covers off and check if the pushrod is seated. Now, so I have this perfectly clear in my head;

I should loosen the outer nut and pull the pushrod toward me to check if it's seated?

peace,
Asaint

[asaint]

FLBMW,

<DOH>! yes, that is perfectly true for Sunday where I performed this procedure 4 times back to back. Talk about me missing the bigger picture..

However, yesterday when I performed the procedure, the bike is stone cold and I still have tiny hammers.

peace,
Asaint

[asaint]

Paul,

Good tip. I need to get over to Sears for a couple tools and will add this to my list. Current list;

1. Torque wrench
2. 11mm Flare wrench (for brake lines -different thread)
3. Needle nose vise grip

peace,
Asaint

[BubbaZanetti]

Randy,

I haven't read the procedure on how to remove the pushrods, but your comments give me pause. Upon reflection perhaps I'll wait on removing the pushrods until all other options have been explored and exhausted. Might be worthwhile to wait until I have someone standing next to me who can guide me through it.

peace,
Asaint

back before i became more confident in my wrenching abilities, i used to be nervous about upsetting anything in the engine that required very precise shimming or torque numbers. that being said, removing the rockers and their associated hardware to pull the push rods is EASY, easier than getting the exhaust off, easier than reattaching the cables to the carburetor and certainly easier than balancing the carbs. you basically just loosen the nuts at the 2, 4, 8 and 10 o'clock positions (in an x pattern), lift the assemblies out as a unit. if it helps, put them on a piece of paper or cardboard and label them (up/down, left/right) so they go back in the right spots. if you keep the assemblies pinched together, they will not come apart. after they are removed you can pull the rods. note which end is which and which rod goes to which valve. you can roll these on a piece of glass to check their straightness. after you confirm this, you can reassemble, this will give you a chance to pinch the rocker assemblies together as you torque the heads, again, looking for just a film of oil as the acceptable end play for the rockers. this does not require much more than a firm pinch from your fingers on either side of the assembly. torque in the same cross pattern you used above, starting at 11 ft/lbs, then 18 then 25, i did mine in 4 steps just to be safe. even if your rods are fine, excessive rocker arm play may lead to excess noise.

[AnnapolisAirhead]

I should loosen the outer nut and pull the pushrod toward me to check if it's seated?
The pushrod should seat on the back side of the valve adjustment bolt (#4). The backside/head of that bolt (#4 in this picture) is a cupped area for the pushrod (#3 in this picture) to seat. #7 is the nut on the outboard side of the valve that you tighten after setting the clearance, it's the easy one to access.

[20774]

you basically just loosen the nuts at the 2, 4, 8 and 10 o'clock positions (in an x pattern), lift the assemblies out as a unit.

In this situation, I would only remove the two nuts for one of the valves at a time. This lessens the change of warping the head with only the 6 and 12 o'clock nuts still tight. After checking the pushrods, put the two nuts back on, torque them some (maybe up to 15-18 ft-lbs), and go after the second set of nuts. Afterwards, perform the stepwise torque for the four nuts.

[BubbaZanetti]

In this situation, I would only remove the two nuts for one of the valves at a time. This lessens the change of warping the head with only the 6 and 12 o'clock nuts still tight. After checking the pushrods, put the two nuts back on, torque them some (maybe up to 15-18 ft-lbs), and go after the second set of nuts. Afterwards, perform the stepwise torque for the four nuts.

good point, better to be safe than sorry.


also, DISCLAIMER: if you don't feel comfortable loosening up the rocker assemblies; don't. wait till you can have a more experienced friend or member help you out.

[Bill Burke]

Upon reflection perhaps I'll wait on removing the pushrods until all other options have been explored and exhausted. Might be worthwhile to wait until I have someone standing next to me who can guide me through it.
Smart move. BTW, it's sort of typical for the ABC to take about 3 months to activate a new membership and get the first Airmail to you (unless something's changed recently). So don't hold your breath on that. Hook up with 26667 or another airhead in Chicagoland as soon as possible. I don't think it's that great an idea for a new airhead owner who's having issues adjusting the valves to head down to Sears for a torque wrench and start disassembling the heads and jugs. But that's just me.

[3moskvichi]

Yes, when the pencil (a dowel rod might be better, to avoid possibly breaking off the pencil tip and getting debris in the cylinder) is pushed out by the piston as far as it can go, you're at TDC. Rotate the engine a few times (without the plugs in) for practice and you'll get used to seeing and feeling exactly where TDC is.

[AnnapolisAirhead]

Yes, when the pencil (a dowel rod might be better, to avoid possibly breaking off the pencil tip and getting debris in the cylinder) is pushed out by the piston as far as it can go, you're at TDC

I use a chopstick, marked with a sharpie and carry it in my tool kit.
(No MSG please) :brow

[asaint]

Hi guys,

Just back in from my evening valve clearance exercise (#6 for you who are counting). No change in the sound.

I checked if the pushrods were pushed into the socket at the end of the bolt. It's just a ball and socket joint - very interesting. I was able to pop the ball out of the socket and push it back in. All appeared to be in and set.

Since I had the heads off I went through the procedure again. A couple thoughts;

1. The exhaust clearance never changes between doing this - always at .20

2. The intake clearance is always too tight - I can't get the .10 feel in there and must readjust each time.

3. I didn't use the pencil trick yet. I like the idea of a long dowel and will find one tomorrow and try it again tomorrow evening using this trick. This appears to me to be the absolute true way of finding TDC.

Man I'm getting good at taking the head covers off and doing this procedure!

Thinking back on it this bike has never really been quiet. My first BMW so I've had no idea what it should sound like.

peace,
Asaint

[AnnapolisAirhead]

Since I had the heads off I went through the procedure again.

...I'm thinking/hoping you you really mean the valve covers off, not the heads. It takes 6 nuts to take the heads off and you are really getting into it then.

Goes like this:
valve cover --- head (the valves and rockers) --- cylinder/jugs/piston --- engine block.

[sumran]

When you tighten the lock nut, how are you keeping the adjuster in place? I put a 12mm wrench on the adjuster and then use a 12mm socket on the lock nut. After the adjusment is done, I rotate the engine again and recheck. If I have done it right no additional adjustment need to be made. I'm just getting the engine to its mark and rechecking with the feeler gauge.

If you are setting it at the correct gap and it is correct on the recheck described above you should be fine. If it is out again after a few minutes of running the engine, there is a more serious problem.

[asaint]

Annapolis,

Yes, you are correct, I'm using the wrong terminology. Wrencher newbie mistake.

I meant the valve covers.

peace,
asaint

[asaint]

Randy,

After I tighten the outer bolt, I check the clearance again. It's at .10. After everything is back together I run the bike for 20 seconds, hear the tapping, shut it down, repeat procedure the next day.

I like the idea of checking again after I spin the wheel and find TDC. That never occurred to me.

Tonight I'll verify that the OT mark is not off by using the dowel trick. If the dowel is fully out and the OT is lined up, then I can eliminate that. I'm thinking of building a little stand with ruler markings on it and sit it right behind the tip of the dowel. This way I can be absolutely accurate when the dowel is fully "out" by checking the highest mark it reaches.

More serious problem - don't keep me in suspense. Lay it on me.

peace,
Asaint

[sumran]

Randy,

More serious problem - don't keep me in suspense. Lay it on me.

peace,

Asaint

:laugh I wasn't trying to keep you in suspense. There are a few possibilities, most of which would involve removing the heads or at least the head nuts. There could be problems with the push rods or the lifters or rocker arms. The cam is involved in the valve action, but I don't know that it would produce that kind of rapid inconsistency. There is also the possibility that your noises are ignition related. It is hard to diagnose without seeing and hearing the bike.

If there is some clearance on the intake, it is unlikely that the excessive noise is caused by a slight reduction in clearance. You should use smaller gauges to determine how much it is closing before you readjust. Checking with a dowel rod may provide another data point, but you are getting a variation in clearance using a consistent mark. Something is moving; it is not just an issue of an improper timing mark.

It is hard to eliminate possibilities because you don't have an established baseline of engine noise. You indicated it may have made these noises before the adjustment (you are unsure about this if I understand your posts correctly), so you can't necessarily attribute the noises to the valve adjustments you have been performing. You have the added disadvantage of not being used to the normal sounds of an airhead. I have not heard your youtube video yet, but noises can be easily distorted or amplified when recorded.

The point of rotating the engine for the second check of the valve clearance is that it checks your completed work. If it is already tightened and it is spot on when you are at the mark, then you can have confidence that the adjustment was made properly.

[535is]

Smart move. BTW, it's sort of typical for the ABC to take about 3 months to activate a new membership and get the first Airmail to you (unless something's changed recently). So don't hold your breath on that.

Email the membership chair and he'll get it done fast.

[asaint]

Happy Update,

Good news for me. A few days ago one of my neighbors stopped in the garage while I was attempting to set the valve clearance. This neighbor has 50 years of experience on every type of engine you can think of. He quietly asked me what procedure I was using, thought about it and gave me a mini class on valve clearances.

Sketches of the valve system appeared on paper towels so I was rooted in the theory. Practical knowledge was gained when he had me remove the head cover and run the engine. Pushing in the rocker arms while the engine was idling was exciting.

Long story short is the engine is purring nicely now. I haven't take it for a ride yet as I'm still struggling with the rear brake problem (different thread).

Interesting guy my neighbor. All he asked in return for his extensive help is that I someday do the same - pass the hands on knowledge on to another newbie biker mechanic.

A big thanks to everyone on this thread. You gave me great advice, technical knowledge and encouragement. However (as many of you indicated), it really takes somebody at your elbow to learn this procedure.

Thanks!
Asaint

[20774]

Asaint -

Just curious...what did you learn from your neighbor and what did you do that made the difference? How was it different than what has been offered by the collective group?

We want to learn just as much as you!

And I'm sure you're looking forward to that nice quiet ride!

[sumran]

That is great news. :clap My favorite part of owning an airhead is the relationships I gained through the experience. You have learned about valves, but more importantly, that house down the street now has a friend in it.

I bet you could even build on that with a dinner and a lesson on brakes. I guarantee you there are hours of amazing stories just waiting to heard.

[asaint]

Kurt,

Here is what we did;

1. I would perform the valve clearance adjustment at TDC. This did not work
2. With the head cover off and the engine running, I pushed in on the ends of the rocker arms. It was immediately apparent that the clearance was HUGE - hence the hammering.
3. Turned engine off, rotated tire until the clearance gap was at it's largest for both rocker arms.
4. Adjust clearance.
5. Put engine back to TDC, rechecked clearance.

It appears that TDC on my bikes is not the point where the clearance is greatest (or at least not this time).

peace
asaint

[asaint]

Randy,

Amazing stories - oh yes - he has a ton of them. Formula 1 pit crew, Performance enhancing Harley's in the 70's, working with Ford engineering, drag racing .. and many more.

He was over yesterday for the great MC rebuild mini disaster. Anyone care to cringe in your chair this morning - ok, here comes the gruesome details....

The rear MC on this bike is in a horrible spot. Clymers has you put the bike on center stand (on a block of wood) and begin the removal process. At some point, Clymer's has you "roll the back tire away from the bike". Problem - the back rear well is in the way. I can't get the tire out.

Sooo.. down to Sears for my first bike lift (note the "first" here ). Get it under the bike, elevate it up and notice it won't go up any further - ooops, I tightened down the strap. No problem, I'll drop the bike down and inch or two, loosen strap and all is well.

I didn't read the lift manual... I turn the lever arm counterclock wise too far and the bike drops like a rock. Now, remember, the rear tire is off and just standing under the bike. Bike goes "BAM!", I reach out to catch it, end up grabbing the lower fairing - tears the lower fairing away from the upper fairing and the bike goes over on it's side pretty hard.

Gas is coming out of my carbs (yes I forgot to close the petcocks) and I'm in shock.

Fortuntately my other neighbor is walking past. He just setup his own auto body biz and he rushes in. He works with jacks and banged up vehicles all day. We get the bike up with the lift under the back luggage carriers and survey the damage.

Amazing, other then the torn fairing and my Sears rolling tool chest that is now dented in, the bike has a few more scratches (body on this bike is in poor shape). These heads on this bike seem really tough - almost like built in crash bars.

I'll be chatting with my auto body neighbor this week and see what he'll charge to fix the fairing. Heck, I might just see what he'll charge for a whole new paint job.

As for details on the brakes, I'll go update that thread. I've hit a wall...

peace,
Asaint

[20774]

It appears that TDC on my bikes is not the point where the clearance is greatest (or at least not this time).

Interesting...once you get past all the other "fun" things, it sure would be nice to confirm the theory and find out where the OT mark is relative to actual TDC. If they're very, very far off, then the flywheel has been put on one bolt hole rotated one way or the other, meaning the bike has been apart before. If they're only 3-5 degrees off, then this flywheel has been badly marked from the factory. I've not heard of that happening very much, though.

[racegun]

asaint...i admire your tenacity & bravery!

lots of good reading: http://www.ibmwr.org/r-tech/airheads/index.shtml

and here:

http://w6rec.com/duane/bmw/index.htm


you will be an expert in short order!

my first attempt at mechanic work was in 1968. I needed to tune up my 1964 ply slant 6 engine. I put the plug wires in the empty plug holes so as not to get the firing order mixed up. Later on, i needed to crank the engine to check the point gap. GUESS WHAT? The plug wires sparked in the open cavity of the block and the damn thing exploded... blew off the valve cover, caught on fire, i took off my clothes to put the fire out, I did not have on skivies, my cloths caught fire, the neighbot girl came out side to see the commotion and etc etc etc. A twenty minute job of changing points took about 19 hrs, all of my pride ( i was in my teens) and yet I still did mechanic work for the next 40 yrs..... hang in there bro!

[sumran]

asaint...i admire your tenacity & bravery!

lots of good reading: http://www.ibmwr.org/r-tech/airheads/index.shtml

and here:

http://w6rec.com/duane/bmw/index.htm


you will be an expert in short order!

my first attempt at mechanic work was in 1968. I needed to tune up my 1964 ply slant 6 engine. I put the plug wires in the empty plug holes so as not to get the firing order mixed up. Later on, i needed to crank the engine to check the point gap. GUESS WHAT? The plug wires sparked in the open cavity of the block and the damn thing exploded... blew off the valve cover, caught on fire, i took off my clothes to put the fire out, I did not have on skivies, my cloths caught fire, the neighbot girl came out side to see the commotion and etc etc etc. A twenty minute job of changing points took about 19 hrs, all of my pride ( i was in my teens) and yet I still did mechanic work for the next 40 yrs..... hang in there bro!

That would make a great movie scene.:laugh It would require careful camera work.

[asaint]

Dave,

Your experience trumps me - nice to hear not everyone slipped into being a wrencher smoothly.

Thanks for the encouragement!

peace,
Asaint