Air box Oil leakage

[peterkenzler]

After a few miles when I shut down my 83 R100RT I get some oil seapage out of the conection between the air box air tube and the carb inlet. The plumbing in the air box apears to be correct.

Any sugestions

[dduelin]

Possibly worn or unseated rings and the associated blow-by allows oil to settle out in the plumbing in the airbox thence leak out the carb elbows. The only way engine oil is getting in the airbox is through the PVC valve and tube that connects to the airbox.

[crazydrummerdude]

Possibly worn or unseated rings and the associated blow-by allows oil to settle out in the plumbing in the airbox thence leak out the carb elbows. The only way engine oil is getting in the airbox is through the PVC valve and tube that connects to the airbox.

PVC valve?

[Slablog]

He meant PCV, or in our case the CCV. I just 20 minutes ago replaced the rubber hose between the CCV and the air box on my R1150R. I thought it was a proper "valve" like cars have, but my dealer mechanic said it was just an open pipe out the top of the crankcase.:dunno

[dduelin]

Yeah, not Polyvinyl Chloride Valve but what whatever, the circular reed valve to the right of the starter motor on top of the crankcase. Nearly bulletproof in your model, it allows blowby gases to exit the crankcase. If there is alot of oil mist in the blowby it settles out and eventually makes its way to the airbox thru a passageway in the top of the crankcase and through the rubber hose that runs next to the starter motor. Check under the air filter to see if you have oil accumulation in the airbox. Just cleaning it out along with the rubber carb intakes in the airbox will temporarily "fix" the oil leak at the carb inlet but does not address the real problem. A clogged air filter will aggravate blowby too.

[Jeff]

The airheads would sometimes blow oil if you lug the engine too often, keep your rpms up and don't lug the engine.

[tghsmith]

check your oil level, R100's don't like to much oil, just above the add mark is fine(if you fill it to the full mark it will find ways of getting rid of it)

[peterkenzler]

Thanks to you all, the rings were replaced as well as the valves just before I bought the bike, only a few thousand miles ago. I first thought oil level but I have insured it is just below the add level.

Still confused though, is the PCV valve a bit that I can replace or is it more likle that the rings are indeed letting too much mist going by.

The bike is running great and if I don,t correct the problem this season I feel like I should be able to ride it long and hard, any body disagree?

[GrantMacEachern]

hi. on my 83RS I have been having a very similar issue. even after a full carb rebuild and topend rebuilt (rings, valves etc etc) i am still getting an oil residue in the intake tubes (tubes between airbox and carb intake). it's a gassy / oily residue. i've never gone in and changed the "reed" valve but may give it a try.

I don't find any oil or residue pooling or collecting in the bottom of the airbox, only where the tubes connect to the airbox.

as for rpms, i definitely keep the revs up...which seems to generate more of this residue.

other than the PCV valve i am at a loss too. the bikes runs great but leaves a bit of a mess around the carbs. would like to get this solved.

g

[GrantMacEachern]

i was just checking an online fiche for the assy of the pcv valve. i've not ventured into that part of the engine but figured if it's just a valve then a quick remove/replace would do it. what i can't figure out is which part and part number is the valve since i have not done this part before. can anyone help out with the part number and ideally a link to the fiche/diagram? i usually refer to max's fiche or the realoem.com website.

i hope this doesn't seem like a thread hijack...i just thought it was the same topic and may be of mutual benefit. g

[peterkenzler]

You go Grant is seems exactly the same issue. I have seen a similar thread before but still have not seen "the right answer"

[GrantMacEachern]

You go Grant is seems exactly the same issue. I have seen a similar thread before but still have not seen "the right answer"

i've tried a few times on boxerworks too. it's hard to diagnose from afar. often i just get:
it's an airhead. it's an older airhead. just ride.
while this is true, it didn't come out of the factory like that and i'd like to fix it if possible. it doesn't stop me from riding but i'd just prefer to get it all buttoned up.

let's see who else is out there to chime in....

g

[kbasa]

There are a couple different case breather configurations. If your bike is making this sound like a turkey gobbling, you're probably due for a new breather.

They're kind of a pain to remove. You need to either use a slide hammer or a little puller to get the old one out. The new one should go right in.

You can buy the puller from these guys: http://www.northwoodsairheads.com/Tools.html

There's a picture of it about halfway down the page.

[GrantMacEachern]

Kbasa, yup, there is definitely a turkey nested in my engine. Thanks for the tip. Much appreciated. Do you think that has an effect on the oil blow-by too?
I've not yet got that far into the engine (under starter cover) to know exactly what you are talking about. I'm sure I can figure it out, but does the puller just back the valve out/off of its mount? Does a replacement valve need any sort of force to remount (i.e. mechanical tightening) THANKS!

[GrantMacEachern]

Hi Kbasa, ok, checked out the puller. seems to make sense now. but:
. should the area be heated first before pulling?
. should the new reed valve be cold before installing?
. do you know the part number for the new valve?
. is assy #3 the part we are looking for in this fiche link:
http://www.realoem.com/bmw/showparts.do?model=0437&mospid=47886&btnr=11_1725&hg=11&fg=10
...and does is simply replace all of what is illustrated in assy #2?
sincere thanks!

g

[donbmw]

When I bought my 1982 R65 that i still had I oil seeping out the intake attached tor carbs. The dealer said to reposition the clamps on the tubes were the worm gears are not on the bottom like they came from the factory. I have done this on this bike for all these years and on my 1975 R90/6 that has to oil breather going on to the RH Carb. I have not had any oil drips when setting. Your are always going to have some oil in the intake tubes. Changing the breather valve will not stop this. Find where you engine oil level likes to go and stay just under the full mark as you add oil.

Don

[20774]

Have a look at this:

http://www.bmwscotter.com/procedures/procedures.htm

It's specific for the /5 but there's a lot of similarity....

[GrantMacEachern]

Have a look at this:

http://www.bmwscotter.com/procedures/procedures.htm

It's specific for the /5 but there's a lot of similarity....
now that's perfect explanation. wow. much appreciated. i think i'll take 'er apart on monday if i get the chance, for an inspection to see what's going on.

g

[ebeeby]

I used the directions Kurt posted a link to above.

You do not need to heat anything. It is an easy replacement. The positioning of the tube as stated in the article is important.

But an upgraded valve is not a cure-all. An over-filled airhead will quite pointedly dispose of the excess (usually in a way for it to end up on your boot).

Often times, filling the crankcase to full with the dipstick screwed in rather than not screwed in as the manual specifies will solve the problem.

[20774]

You may want to check something else regarding the path of the oil mist as it leaves the breather. On my /7, the oil mist out of the breather first runs forward into a channel that's built into the top of the engine case. Just forward of the breather in this channel is a small well with a tiny hole in the bottom. This is designed to let condensed oil drain back in the case. After that, the oil mist is routed forward where it turns 180 degrees and heads back to be send to the carbs. Check to be sure this small hole is clear. Find a fine piece of stiff wire and clear the hole. Don't drop the wire into the case...put a bend at the end to prevent it from falling through. I'm sure you can imagine the doo-doo you'd be in if it fell through.

[JETHRIDGE]

I have an 83 R100 RT. I noticed Oil On the rear of the Transmission. Thinking it was the Clutch Lever Seal Leaking i had it Replaced. Still Got Oil On the rear of the transmission. Pulled the Air Cleaner an found that the Vent Tuber (Hose) from the crank case had some Sort of thing With sponge in it, Full of oil and leaking to the rear of the tranny. (All The pulition control stuff removed by PO) I went to
true Value and
Bought a T that would fit the vent hose and Ran a tub (Hose) to each carb. Now The oil mist goes in the carb and burned up. No oil on the tranny.

[peterkenzler]

Well done I have a turkey in my engin as well. I am ordering the new valve today.

Thanks for takeing over the thread it was a big help..

[GrantMacEachern]

i'm picking up a valve tomorrow as well. it'll give me something to do. essentially an experiment. i'm praying the turkey flies away, otherwise it may be another issue as noted earlier - main seal or timing cover.
g

[peterkenzler]

Just took a peak at the valve. It seems on the 83 RT the starter will need to be removed in order to access it. I am thinking I will wait untill I need to service the starter before I tackle the valve replacment..

[JETHRIDGE]

I have an 83 100 RT and had the same problem. When I pulled the Air Cleaner Cover I found that All The polution crap had been removed by PO> Attached to the end of the Hose that comes out of the crank case was a Filter of some sort with foam full of oil. I went to true value and bought a "T" that fit the breather Hose and Had a conection for a smaler hose to each side. I attached a short pc of hose to the Rt & Left Outlet and ran it to the carb tubes( An inch or so) No more problems. I have no knowledge of CPV,PVC, or What ever valve mentioned. Mine workes Great Without one so why bother, just vent the crank vent to each carb and burn up the oil mist. I had an R90/6 that I fixed this way and no problems.

[DennisDarrow]

Grant......there are a couple of articles over at "Airheads". No you do not need to purchase any special tools......

Did this job a couple of months ago and discussed it here: http://www.bmwmoa.org/forum/showthread.php?t=23640&highlight=breather+valve

Vech has the part on hand and will have it to you very quickly. The best part about them is that they take the time to talk with you about what you need and how to fix it.

Really is an easy job. Be careful about which direction you "point" the screw when you put it back in.
Dennis

[GrantMacEachern]

hi dennis et. al.
ok, so yesterday with a cold one in hand off came all the covers etc to go at the breather valve (which I have a new one). like mentioned above I noticed the starter blocked access to one of the allen bolts for the valve cover. drat. after encouragement from boxerworks forum I went further to dissassemble the fairing, the front cover etc etc. The only problem was I just couldn't get the mounting bolt at the left rear of the starter to free up. The space is so tight in there and I didn't have a tool to get the nut off. My socket would fit on but the drive head was too big. It was suggested to use a 1/4" flex-head ratchet, which I didn't have. I contemplated going out and driving around all day looking for one and just decided to button everything back up and take it out for a spin. I still get the turkey gobble but I'll have to save the valve replacement for another day. I feel a bit dejected but I just didn't have it in me to go further. Someday I'll pick up the ratchet and give it a go again.
tks all!

check out www.boxerworks.com and go to the message boards / general BMW discussion. My post is titled
Gaining access to the crankcase breather valve - help
dated June 7.

Good info from Hugh too! Thanks everyone.

[peterkenzler]

Grant I am glad I did not go in, I am heading out to CA and WA in a few days from here in Flagstaff and I just did not want to go that deep in with out the luxury of time.

This may seem strange but one of the posts sugested rotating the hose clamps so that the knurl and slots are at the top instead of at the bottom of the conection. I tried it, went for a high speed run and low and behold no drips. I supect the oil will again find it's way outside but I can say it did make a difference..

[donbmw]

This may seem strange but one of the posts sugested rotating the hose clamps so that the knurl and slots are at the top instead of at the bottom of the conection. I tried it, went for a high speed run and low and behold no drips. I supect the oil will again find it's way outside but I can say it did make a difference..

Have done this since early 1982 the only oil I get is when a valve cover gasket, oil press switch or some other gasket start leaking. By the BMW breather systems you are going to have some oil in the intake all the time.

Don

[GrantMacEachern]

Grant I am glad I did not go in, I am heading out to CA and WA in a few days from here in Flagstaff and I just did not want to go that deep in with out the luxury of time.

This may seem strange but one of the posts sugested rotating the hose clamps so that the knurl and slots are at the top instead of at the bottom of the conection. I tried it, went for a high speed run and low and behold no drips. I supect the oil will again find it's way outside but I can say it did make a difference..

yup, been rotatating the screw on the hose clamps to the top position for some time now. seems to help a bit but not solve the overall issue.

[donbmw]

yup, been rotatating the screw on the hose clamps to the top position for some time now. seems to help a bit but not solve the overall issue.

To solve the issue you are going to have to learn to live with it. Do the the designe of the breather system some oil is going to be in the intakes.

Don

[GrantMacEachern]

To solve the issue you are going to have to learn to live with it. Do the the designe of the breather system some oil is going to be in the intakes.

Don

that's what i've been coming to terms with. thanks!

[bearsfolks]

What kind of air filter do you have? Stock paper or K&N? I over-oiled my K&N and got this oily mess on the left carburetor hose and float bowl.