My 1100GS rattles but I can't trace it!

[steve case]

I have a mysterious tapping/rattle in my engine and I cannot work out what it is.

It is from the front of the engine not the heads (I've checked the valve and rocker clearances), It appears when the engine is warm (at least 4 bars showing) and even then its not continuous.

One thing I 've noticed is that once I overfilled the oil and the engine was silent, when I realised I'd put too much in and took some back out the tappy rattle was back.

I thought it was from the timing chain to the auxiliary shaft and replaced these and the tensioners which although needed (the tensioners were badly worn) the rattling tappity sound was still there.

Please if someone has an idea what this could be please let me know as I am at the point of looking for a new engine!

Steve

P.S is this really an Adolf smilie?!?!? The mind boggles!

 

[MattW]

I'll jump in first.

Have you checked the camchain tensioners - especially the left tensioner - is it the updated version or the original item with separate spring, piston and housing?

Edit: Scratch the throttle body thing - high oil level wouldn't quieten them
Throttle bodies?

I'm sure others will contribute more ideas.

cheers
Matt

 

[steve case]

Thanks Matt

Thanks Matt, but the cam tensioner on the LHS is brand new and the RHS I looked at....but it does ask another question, how many miles will the cam chains do. They are a long run and although they are supported by the tensioners they must have a lifetime!

 

[Bronco Billy]

Youve not left a couple of spanners in your pocket have you! ....



Curl your finger round the right hand throttle body and put some pressure from the inside on the end of the shaft that turns the butterfly. its connected by the throttle cable quadrant. If the tapping goes away then it means youve got a worn TB spindle.

Pound to a penny thats what it is ........

 

[MattW]

Thanks Matt, but the cam tensioner on the LHS is brand new and the RHS I looked at....but it does ask another question, how many miles will the cam chains do. They are a long run and although they are supported by the tensioners they must have a lifetime!

I guess everything wears out in the end, although I've no idea what the projected lifespan of a camchain is. How many miles on your engine? How's oil pressure (no flickering light at tickover)?

Another thing that I have heard of causing problems (although its very rare) are the camchain tensioner blades (the black plastic guides which the chain runs in - one of which the tensioner assembly bears on). From what I've heard, these only usually give problems at very high mileages or as a side effect of some other event (duff cam chain tensioner etc).

I guess if you're positive that an oil over-fill quietened everything down then it sort of narrows down the possibilities (i.e. excludes things like throttle body balance, alternator, starter clutch etc).

I'm afraid that's me out of ideas - hopefully Steptoe or one of the other guru's will notice this and chip in

good luck!
Matt

 

[Decster]

.....
I'm afraid that's me out of ideas - hopefully Steptoe or one of the other guru's will notice this and chip in

..and before he does, lets have the year of bike and anything else that might help, modifications, milage, pics and more pics...have you serviced it yerself recently and what service it got.....

 

[ianboydsnr]

have you checked the rocker end float?

 

[MattW]

......

It is from the front of the engine not the heads (I've checked the valve and rocker clearances)

 

[ianboydsnr]

have you checked the rocker end float?

That does'nt mean thats not the cause

 

[MattW]

That does'nt mean thats not the cause

True enough , but you asked if he'd checked them and I quoted from his initial post which says he has

 

[steve case]

Thanks for all your replies

The bike is an R1100GS with a build date of June 97, the mileage is unknown it shows 64K but I ran it for 7K with the speedo cable broken when I was commuting on it and I suspect the 1st owner did the same, I can only say
70K+.

Its not the throttle bodies as one of mine is worn and ticks but not badly, I checked the rocker end float as I have had this in the past and they are about 0.10mm (also rocker end float noise is usually on one side and this is both). I thought it was aux chain and tensioners so replaced these (they were worn) but the noise remains.

The odd thing was the high oil level quietened it so it has to be low in the engine, also it only occurs when warmed up and the rockers tend to get quieter and that it fades in and out which made me think it was the chain.

It could also be that I've buggered up fitting the chain but I would think this would be a little more terminal and get a lot louder very quickly closely followed by a long silence!

 

[steve case]

Oh also

I forgot to say, yes it could be the cam chain tensioner blades, if it is are these replaceable without splitting the main casing?

And no its not loose spanners (or nuts) as I was standing next to the bike after riding it to see if had quietened down. Nice try though!

 

[Stewart H]

I forgot to say, yes it could be the cam chain tensioner blades, if it is are these replaceable without splitting the main casing?

And no its not loose spanners (or nuts) as I was standing next to the bike after riding it to see if had quietened down. Nice try though!

It is rumored that theres a cheat for the cam chain tensioner blades that avoids the need to split the crankcases, someone posted over on ADV rider a method where the old ones were cut off with a wire saw and the new ones (which pivot on a steel pin) can have a slice taken out of the locating eye, enabling them to be clipped into place, merely needing the removal of heads and barrels, But the poster deleted the thread and images, probably making a living doing them now I believe Steptoe can perform this procedure, I would certainly give it a try before going fully drastic and removing the motor, I have a 97 1100 too and used to be alarmed by some of the sounds, I always wear earplugs they are not the quietest, one thing I found was that the throttle cables need virtually no slack at all.
Stewart

 

[MattW]

Saw this thread and thought of you - might be worth checking your cam followers?:

http://www.ukgser.com/forums/showthread.php?t=187775

cheers
Matt

 

[asnore]

If you have any questions about checking camshaft and cam followers, feel free to ask.
By the way, as the head nuts should be removed, torque wrench is needed, also cam sprocket bolt has to be tightened with a great force and bolt lock should be applied there.
Regards,
Andris

 

[steve case]

OOOO! I never even thought of that!

Blimey I would never even have thought of that one, I think I will have a look at the followers this weekend
Thanks for everyones help
Steve Case

 

[Steptoe]

Don't forget to check the pushrods. BMW changed the design a couple of years ago because of the problem .

The ends become loose on the old style rods, and cause a rattle/knocking. The play on the pushrod only becomes apparent when it's hot.


The picture below shows what happens.



The old style is above in the picture below, the new style is underneth.