1100 GS broken timing chain guide. Call for help

[danbarnettphoto]

A call for help (info) to BMW oil head wrenchers out there. I sent my 1995
BMW R 1100 GS to my local mechanic (non-dealer) to replace the leaking head
gasket on the left (driver’s side) cylinder. When he pulled the head he
discovered the upper timing chain (plastic) rail was broken off about 1/3
distance from the pivot point. This rail covers the top part of the timing
chain and is pressed upon by the timing chain tensioner which causes it to
press against the timing chain and I suppose suppress timing chain noise.
The shattered pieces were lying about the engine and he removed all that he
could see. The lower timing chain guide rail was intact.

I can see three possibilities.

1. Obtain a new upper timing rail and try to slip the old one out and the
new one in without further dismantling (splitting) the engine. He says
maybe, I say it is a long shot due to limited clearances inside the engine.
If anyone has ever tried, and or succeeded at this task please let me know
as soon as you can. This is my one chance to fix it right at a reasonable
price.

2. Leave it as is. The engine was running perfectly. I only removed the
head to replace the head gasket due to a leak bad enough to give me an oil
wet boot after every ride. I heard no excessive noise. I can remove the
spring and piston from the tensioner leaving just the plug to seal the
engine. I am hoping to get another year or two out of the bike and upgrade
to a 1200. If the timing chain guide is mainly to suppress chain noise I
could live with a little noise and disclose the issue to any future owner
and discount the price appropriately.

3. Haul it to the dealer 40 miles away and bite the bullet. The bike is in
good shape and has 75k miles on the clock. I am guessing $2 to 3K to pull
and rebuild the engine. It is hard to put that into a bike that will never
be worth more than about $5,000 due to age and mileage.

I am open to and grateful for any and all suggestions

Dan Barnett

e-mail danbarnettphoto @ msn.com

Phone 561 329-4087 from 9:00 am to Midnight EST

December 5, 2006, See post below for happy ending!

[danbarnettphoto]

A call for help (info) to BMW oil head wrenchers out there. I sent my 1995
BMW R 1100 GS to my local mechanic (non-dealer) to replace the leaking head
gasket on the left (driver’s side) cylinder. When he pulled the head he
discovered the upper timing chain (plastic) rail was broken off about 1/3
distance from the pivot point. This rail covers the top part of the timing
chain and is pressed upon by the timing chain tensioner which causes it to
press against the timing chain and I suppose suppress timing chain noise.
The shattered pieces were lying about the engine and he removed all that he
could see. The lower timing chain guide rail was intact.

I can see three possibilities.

1. Obtain a new upper timing rail and try to slip the old one out and the
new one in without further dismantling (splitting) the engine. He says
maybe, I say it is a long shot due to limited clearances inside the engine.
If anyone has ever tried, and or succeeded at this task please let me know
as soon as you can. This is my one chance to fix it right at a reasonable
price.

2. Leave it as is. The engine was running perfectly. I only removed the
head to replace the head gasket due to a leak bad enough to give me an oil
wet boot after every ride. I heard no excessive noise. I can remove the
spring and piston from the tensioner leaving just the plug to seal the
engine. I am hoping to get another year or two out of the bike and upgrade
to a 1200. If the timing chain guide is mainly to suppress chain noise I
could live with a little noise and disclose the issue to any future owner
and discount the price appropriately.

3. Haul it to the dealer 40 miles away and bite the bullet. The bike is in
good shape and has 75k miles on the clock. I am guessing $2 to 3K to pull
and rebuild the engine. It is hard to put that into a bike that will never
be worth more than about $5,000 due to age and mileage.

I am open to and grateful for any and all suggestions

Dan Barnett

e-mail danbarnettphoto @ msn.com

Phone 561 329-4087 from 9:00 am to Midnight EST

[PGlaves]

A call for help (info) to BMW oil head wrenchers out there. I sent my 1995
BMW R 1100 GS to my local mechanic (non-dealer) to replace the leaking head
gasket on the left (driver’s side) cylinder. When he pulled the head he
discovered the upper timing chain (plastic) rail was broken off about 1/3
distance from the pivot point. This rail covers the top part of the timing
chain and is pressed upon by the timing chain tensioner which causes it to
press against the timing chain and I suppose suppress timing chain noise.
The shattered pieces were lying about the engine and he removed all that he
could see. The lower timing chain guide rail was intact.


Voni's R1100RS did this several years ago. It was not possible to replace hers without removing the engine and splitting the cases, so I did that. I'm in Texas - my manual is in Kansas, so this is from memory.

Two of the 4 guides are on a pin captured by the two case halves. Splitting the cases is necessary to replace either of these two. The other two are on stub shafts with circlips on exposed ends which theoretically could be unclipped and replaced. But there is a very severe limitation to the lateral clearance to slide the guide sideways and it would take needle nose pliers about 8" long to remove and replace the clip. And a very steady hand and probably a decent supply of clips on hand too. And I'm not sure with the clearance limitation that it is even possible.

I think in your case this is academic. I just looked at a cutaway drawing and the top guides are the two captured on the pin between the case halves. That is the movable guide on the left side and the fixed guide on the right side.

You are down to two choices: leave it alone or pull and split the engine.

I suspect it would run many miles if you just left it alone. It really depends on several factors - where the break is, how brittle it is, and why it broke in the first place. If the tip broke off and the "block" on the guide that the tensioner rides against isn't cracked or brittle you could probably ride with the defect. If it is brittle and the tensioner "block" is cracked and breaks off then the chain goes slack, starts slapping, and all bets are off as to further damage. There is a risk of shards either blocking the oil pump intake, and or getting sucked through the screen into the oil pump.

Been there - done that - and can't think quite what else to tell you.

[PGlaves]

See my reply on the other thread with this same post.

[jeffsdale]

http://i31.photobucket.com/albums/c359/gsbiker/IMG_4015.jpg

http://i31.photobucket.com/albums/c359/gsbiker/IMG_4018.jpg

Here are a couple shots of the interior of a R1100 block I have on the bench right now. The plastic rail you can see is the left upper rail. You can see the pin and the groove where the "C" clip rides. The metal pin sticks through the block. As you can see in the lower picture the pin is located at the point where the block splits.

What would happen if you loosened the bolts that hold the block together just enough to allow the pin to be pushed to the rear allowing the plastic rail to be removed and replaced?? I guess you would run the risk of not being able to seal the block back together.

Just a thought. Maybe somebody else can chime in with a suggestion.

-jeff

[cjack]

Most of the time, it's faster to just fix something than to try to work around it.

[jeffsdale]

Most of the time, it's faster to just fix something than to try to work around it.

Sounds like the voice of experience.

[danbarnettphoto]

Thank you all for the advice. I will have the part tomorrow and will try to slip it in. I do not think I have the clearance. I really do not have the knowledge to remove and split the engine myself. My local mechanic does not either. Dealer option looks expensive. I will let everyone know if we are successful. DanB

[jeffsdale]

Thank you all for the advice. I will have the part tomorrow and will try to slip it in. I do not think I have the clearance. I really do not have the knowledge to remove and split the engine myself. My local mechanic does not either. Dealer option looks expensive. I will let everyone know if we are successful. DanB

So? What was the outcome? Were you able to fit the chain guide without splitting the case?

-jeff

[danbarnettphoto]

I took my 1995 BMW R1100 GS to my local mechanic Joe Taffuri in West Palm Beach because it was leaking a little oil from the left (drivers side) head gasket. When Joe removed the head he found the left upper cam chain rail shattered. This black plastic ($10.00 part) rail sits on top of the cam chain and is pressed down upon by the cam chain tensioner (a simple metal plunger with a spring to provide pressure). The rail is attached at a single pivot point on a metal stud about six inches inside the engine. The rail is over 10 inches long and extends out into the cylinder head. A few calls determined that the manual calls for the engine to be removed and split to install the part. That could mean $1500.00 to $2000.00 or more to replace a $10.00 part on a $5000.00 motorcycle. Joe thought he could snake it in. I thought the clearance was not there. I put out the word on BMWMOA and my GS mailing list. Anton Largiader from the mailing list suggested it could be done if we broke off a corner of the baffle at the left of the pivot point to give the approximately ¾ inch clearance needed. I gave Joe the O.K. and he surgically removed the old one and installed the new one after removing a corner of the baffle. I have included a picture to show the baffle and chain guide as best as I could. This is a big deal as it saves a huge amount of labor, and/or money if anyone has this problem. Thanks to Anton and all who replied and to Joe Taffuri for his careful surgery.
If you cannot see the pictures here try the BMWMOA forum “Oilheads” and look for “1100 GS broken timing chain guide. Call for help”

"OOPS, it seems I cannot post my picture but if you look at the fine picture posted by jeffsdale you will see the pivot point and the end of the rail. The baffle is down and to the left of the pivot point. It is thin like the one above and to the left. Joe broke off the corner and saved the day.

[cjack]

Anton Largiader from the mailing list suggested it could be done if we broke off a corner of the baffle at the left of the pivot point to give the approximately ¾ inch clearance needed. I gave Joe the O.K. and he surgically removed the old one and installed the new one after removing a corner of the baffle. I have included a picture to show the baffle and chain guide as best as I could. This is a big deal as it saves a huge amount of labor, and/or money if anyone has this problem. Thanks to Anton and all who replied and to Joe Taffuri for his careful surgery.
.

Originally Posted by cjack
Most of the time, it's faster to just fix something than to try to work around it.

And sometimes not. Great job. I actually came across this issue once and although it didn't result in an easy answer due to other issues, I'll remember this fix.

[AntonLargiader]

Here's the solution Dan used:
http://www.largiader.com/misc/chain_rail.jpg

[mcholt212]

It's been a few years since this thread was created, but I now find myself in this very same predicament. Actually, my case is a little more severe....seems when my left side lower guide rail broke the chain slap was so severe (or I was able to ignore unusual sounds for long enough) that the top rail went too. And, as if my day didn't suck enough at that point, I lost my tension piston and spring into the motor as well. Man, you should have heard the clanging in the motor at that point.

2002 R1100SA with 54,000 miles.

After two weekends (about 14 hours total) I now have the motor all by itself strapped to a lift and I'm ready to pull the heads, pistons, conrods and split that sucker in two.

I am doing it myself because I don't have the 2K to give Tom Cutter at Rubber Chicken Racing to do the job (sorry Tom!)

I just hope I can get the thing back together by summer. I've taken lots of pictures during the teardown, notes, labeled and tagged wiring and put all bolts back in their place after removal of respective parts.

One question.....why would the Motherland load PLASTIC rails into an oil cooled motor?????

Anybody that's been there and done that please feel free to share any tips/tricks! I'd love to know if there are any special tools I can get around using inside that case. I've made my own gearbox guide pins, TDC lock, etc....but the stuff the manual shows you using in the case (like alignment attachments, etc) I'm not so sure about shortcutting...