MOTOR GURU'S HELP part 2

[dabreitbach]

I have everything pulled apart see http://www.spyderlovers.com/forums/showthread.php?33569-motor-problem-HELP-From-the-motor-guru-s and I can find no wear or bad parts anywhere. Even the chain is still well with in specs. No play in anything or wear marks any. Here are pics of the broken adjuster guide and the bottom timing gear. You can see the wear marks on the chain guide are the heavyest at the bottom were it broke very close to the bottom timing gear. The wear marks are pretty heavy at the top also. But look at the last pic. There is almost no wear in the middle of the guide and thats where the tensioner pushes against the back of the guide. You would think that since the guide has a reverse curve, that point would have the most contact with the chain and the most wear but there's almost none. Correct me if I'm wrong but I think I have a bad tensioner.

Now if that is the case would you just get a new tensioner and guide since everthing else is good and in spec or would you get a new chain and gear also.??? Let me know what you guys think

 

[NancysToy]

I am concerned that the guide shows evidence of either being contacted by something on one side, being squeezed at the bottom, or of being forced sideways by misalignment. That makes little sense, with how it is built and the good condition of the chain, but the break is not even and there is a chunk out of it in a place where you would not expect that to happen after the fact. Are you sure the missing bolts did not go down into the engine and kill the guide? Are the other guides properly aligned? Are the bolts properly torqued and was Loctite used where required? How about the drive gears? Good condition, needle bearings good, and thrust washer the proper one in the proper place? Any slop or misalignment there could cause contact or lateral tension. Also check the sleeve at the end of the guide. If it fits loosely, or does not support both sides of the guide, it could cause this kind of breakage.

You did not say anything about the tensioner itself, or show it. Is it in good working order? Does it move freely and apply tension to the guide properly? Was it oiled when installed, and is it receiving lubrication? This is really the critical part of the system. If it doesn't apply the proper tension, it could lead to the problems you have shown.

If everything is in good working order, I would replace the guide...or maybe all three of them, if available, and I would replace the chain, just for luck. I personally would probably also replace the tensioner assembly, but BRP lists them as "Not available".

 

[dabreitbach]

If the bolts went down thru they would of taken everything out including the cylinder. There is just no room and the bolts are almost 2 inches long with washers. All other guides are in good shape, so are the needle bearings and all washers and thrust washers are good. The drive gears are good and all the timing marks lined up. The sleeve on the bottom of the guide has no slop and fits tightly into guide.
The tensioner looks good to me. It compresses like it should and springs back smoothly and appeared to be well lubed. The only thing I cant tell is if it is giving enough tension or pressure. I suppose I could pull the front one to give me something to compare it to. Also there are absolutely no wear marks on the case or cylinder timing chain galley or anything else that shows any kind of lateral movement. All the spaces are pretty tight and would show any lateral movement. Now the sleeve on the bottom of the guide fits pretty tight and would not let the guide float on it easliy to keep aligned with the chain. Maybe that could be the problem and the missalignment is coming from?:dontknow:

 

[NancysToy]

.....Now the sleeve on the bottom of the guide fits pretty tight and would not let the guide float on it easliy to keep aligned with the chain. Maybe that could be the problem and the missalignment is coming from?:dontknow:

I would agree. This may be the weak link. Whether it was that way from the start or got that way in time is hard to say. I think I would replace the sleeve, too, and fine tune the fit before reassembly. Not sure whether the guide moves on the sleeve, which would require it to be looser, or the sleeve moves on the bolt/post, which would mean a tight fit was better. I expect the latter, just because of the wear factor. If the sleeve fits too tightly though, they could have cracked the guide when they inserted it originally.

 

[MikeinGA]

I have everything pulled apart see http://www.spyderlovers.com/forums/showthread.php?33569-motor-problem-HELP-From-the-motor-guru-s and I can find no wear or bad parts anywhere. Even the chain is still well with in specs. No play in anything or wear marks any. Here are pics of the broken adjuster guide and the bottom timing gear. You can see the wear marks on the chain guide are the heavyest at the bottom were it broke very close to the bottom timing gear. The wear marks are pretty heavy at the top also. But look at the last pic. There is almost no wear in the middle of the guide and thats where the tensioner pushes against the back of the guide. You would think that since the guide has a reverse curve, that point would have the most contact with the chain and the most wear but there's almost none. Correct me if I'm wrong but I think I have a bad tensioner.

Now if that is the case would you just get a new tensioner and guide since everthing else is good and in spec or would you get a new chain and gear also.??? Let me know what you guys think

I worked on one that was wearing tensioners at a fast rate. It was the due to the chain. The chain links were worn in one part of the chain, causing chain to vibrate. The fix was thet they found a better quality of chain. If you have modified the engine to increase the power output may find other EOM parts that will not take the stresses of the modifications.


Mike

 

[dabreitbach]

Got my parts late this afternoon. Took my time and double checked everything as I assembeled it. I have all gears,chains and balence shafts back in. Clearences and all tolerances are good. Everything is timed as it should be. Tommorrow morning all I have to do is install the clutch, clutch housing, radiator and valve cover to finish. Those will go real fast because they were not the problem.
I think it was to tight of a fit between the chainguide and the sleave that goes in it. It would not let the guide to (float) to keep aligned with the chain. The new guide has alot looser fit with the sleave than the old one did. I guess I will keep an eye on it and see if I'm right.ray:ray:opcorn:

 

[NancysToy]

:thumbup::thumbup::thumbup: Here's to a successful test ride and many carefree miles to come!

 

[dabreitbach]

Test ride and a joy ride and everything is great. Boy the engine is sure quiet now. Can Hardly hear it.:clap: