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Discussion Starter · #1 ·
hello all,



i recently embarked on my first engine drop to fix a shifting problem which turned out to be a broken can chain tensioner guide and arm.

well, the GOOD NEWS is i got all oem parts and buttoned it all back up with a new gasket and o-rings.

The BAD NEWS is that i've got it back on the bike and went to do the cam chain adjustment and the bolt doesn't tighten.

Now my confusion come into the picture as I don't understand why it needs to be locked down if it's supposed to be an "automatic" chain tensioner?



I haven't run it (haven't even put the oil in yet) but i was NEEDING to do that tonight because I have a road test for my motorcycle license in two days!!

Is the locking down of the bolt crucial?

Is this an engine out thing?

I've read other posts with similar problems so i think i know the answer (engine out) but i don't understand why based on it being supposedly an automatic tensioner.



Thank you.
 

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hello all,



i recently embarked on my first engine drop to fix a shifting problem which turned out to be a broken can chain tensioner guide and arm.

well, the GOOD NEWS is i got all oem parts and buttoned it all back up with a new gasket and o-rings.

The BAD NEWS is that i've got it back on the bike and went to do the cam chain adjustment and the bolt doesn't tighten.

Now my confusion come into the picture as I don't understand why it needs to be locked down if it's supposed to be an "automatic" chain tensioner?



I haven't run it (haven't even put the oil in yet) but i was NEEDING to do that tonight because I have a road test for my motorcycle license in two days!!

Is the locking down of the bolt crucial?

Is this an engine out thing?

I've read other posts with similar problems so i think i know the answer (engine out) but i don't understand why based on it being supposedly an automatic tensioner.



Thank you.


Sounds like you need to pull the back cover again unfortunately. The '79 isn't a "auto tensioner". It's a pretty light weight spring, and won't hold the tensioner against the chain unless it's locked. Later models (like my '83) with the true auto tensioner has a pretty high tension spring that puts a significant force against the chain to hold it.



Here is the auto tensioner:







Here's yours:



 

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The 500's are not fully automatic.



"Rotate the engine again to TL and back off the cam chain bolt near the inspection cover 1 1/2 to 2 turns out. Don't go any farther or serious problems could happen. Then tap the side of the engine/bolt with a mallet a couple times. This action will move the spring loaded cam chain if for some reason it is stuck. Some also suggest to rotate/rock the crank bolt that you have been turning with the ratchet slightly back and forth so the adjuster falls into the right place. Then tighten up the cam chain bolt again. It is a low torque bolt so if you do any more than 6-9 pounds it could strip or snap. Then put the bike back together and run the engine. "



And another description...



" Whilst we are doing this job I mentioned the Cam chain Adjustment.Whilst you have the Left hand side Cylinder at TDC you can slack off the 10mm Adjuster nut just above the rear inspection hole around 2 turns.This will release the spring operated mechanism inside the engine that pulls the Cam chain tight so you get Two jobs done for the price of one.Re-tighten firmly but again do NOT over tighten as these are M6 bolts and have a max!!!! Torque of 9 Ft lbs and are easily stripped." (from the link below)



see here for some help. Those who actually have a 500 should chime in...
 

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Discussion Starter · #5 ·
okay cool. so i don't have an auto tensioner.



as for what i saw before i closed it all up, the spring was holding the guide right up against the chain with a good amount of pressure. And the Arm had the entire slot open for future movement. Is it supposed to have that full spring pressure? or is there supposed to be some breathing space for the chain to slide along the guide?
 

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okay cool. so i don't have an auto tensioner.



as for what i saw before i closed it all up, the spring was holding the guide right up against the chain with a good amount of pressure. And the Arm had the entire slot open for future movement. Is it supposed to have that full spring pressure? or is there supposed to be some breathing space for the chain to slide along the guide?


Normally, when you release the bolt the full spring pressure will press the tensioner blade against the chain, removing the slack. When you lock it down, the blade will stay put. The idea for periodic adjustment is to keep the blade moving in to take out the slack.



If yours isn't locking the tensioner down, when you run the engine the chain will push the blade backwards because the spring tension isn't enough to hold it there, and you might as well have no adjuster at all in that case.



Good news is you already know how to drop her, so I will be much quicker this time 'round. Hopefully all is well with the bolt on the inside.
 

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Discussion Starter · #7 ·
i had some threading issues with the bolt when it was opened up. The bolt didn't want to go back into the threads in the engine. I ended up tapping the threads to clear any damaged ones and it went back in no problem after that. only it never tightened up.



what i think is happening is that it felt like the threads on the bolt have gone past the threads in the engine. So it IS locked in there but not locked down.



This is my ultimate question. If I know the bolt wont come out, am I all good?

Or if not all good, how long could i be good for?



I kinda want to just pass my road test and not have to pay for everything all over again.
 

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I don't think the bolt adds any tension, it just holds the tension the spring exerted when the bolt was loosened. If the bolt is not holding the adjuster from moving, there will not be enough tension on the chain, as stated in the other posts.



As far as riding it this way...you are taking a chance but possibly it will be ok if you run VERY easy and baby it till you can fix this issue...your call really.



BTW Abes-CW, I was referring to myself as a non 500 owner, and did not see your post until after I posted mine.
 

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Discussion Starter · #9 ·
Normally, when you release the bolt the full spring pressure will press the tensioner blade against the chain, removing the slack. When you lock it down, the blade will stay put. The idea for periodic adjustment is to keep the blade moving in to take out the slack.



If yours isn't locking the tensioner down, when you run the engine the chain will push the blade backwards because the spring tension isn't enough to hold it there, and you might as well have no adjuster at all in that case.



Good news is you already know how to drop her, so I will be much quicker this time 'round. Hopefully all is well with the bolt on the inside.


Thanks. Thats the kind of knowledge i was looking for.

So frustrating. But best to do it right.



D.I.Y (do it yourself)

D.I.R (do it right)
 

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Discussion Starter · #10 ·
I don't think the bolt adds any tension, it just holds the tension the spring exerted when the bolt was loosened. If the bolt is not holding the adjuster from moving, there will not be enough tension on the chain, as stated in the other posts.



As far as riding it this way...you are taking a chance but possibly it will be ok if you run VERY easy and baby it till you can fix this issue...your call really.



BTW Abes-CW, I was referring to myself as a none 500 owner, and did not see your post until after I posted mine.


Thanks for the help.

I love that everyone is so willing to help. This place Rocks!
 

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Discussion Starter · #11 ·
Does anyone living in the GTA (toronto, Ontario) want to help a brotha out and lend me their bike for wednesday May 18th at 2:30 so i can take my M2 road test?



Anyone?



Aghh!
 

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This is my ultimate question. If I know the bolt wont come out, am I all good? or will there be TOO MUCH tension on the chain?



No you wont have too much tension, you'll have too little

I think its been established you have a manual tensioner on your 79er



Normally when you set the manual adjuster, loosening the bolt allows the

setting spring to flex the guide against any play in the chain.

Once it takes up position the bolt clamps the guide in place

and the setting spring does no further work.

When the engine is running the continual tension and release of the chain

acts against the slightly flexible guide.



With a loose clamp bolt, the guide will be unable to hold tension and

the adjuster arm will be nodding up and down with only the setting spring

trying to push it back.



Not an ideal situation.
 

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Being only a month old '82 GL500, I'm quickly absorbing all the great knowledge on this forum. After reading this thread, I now know what the huge glob of RTV was supposed to repair. I guess I'm dropping the engine…
 

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If it's a new chain and guide, I'd take my test on it. With a new chain and guide, the chain stays really tight as the motor turns, even without the cam bolt set.
 

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Being only a month old '82 GL500, I'm quickly absorbing all the great knowledge on this forum. After reading this thread, I now know what the huge glob of RTV was supposed to repair. I guess I'm dropping the engine…
do not rush into that conclusion.your issue may be the oil seal failing.not,an engine out job.
 

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for a 79, is it enough to loosen the tensioner/hold down bolt a 1 to 2 turns give her a rap, and hope the spring does its job? I remember the first time ever adjusting the cam follower I loosened the nut, and never really rapped on it, just sorta assumed the spring did its thing, and the tensioner is in its place.



With the cam follower hold down bolt loose, has anyone ever opened the inspection port and pushed on the backside of the follower to make sure it moves and contacts the timing chain?



With the aid of a dental mirror, can the follower be seen contacting the chain? I just want to make sure mine is adjusted properly is all.
 

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Discussion Starter · #17 ·
i dropped the engine last night and tapped more threads into the tensioner bolt hole. and now it locks tight! what a relief! im a little worn out having dropped the engine twice in as many days, but its all good now. and im all the more aquainted with my bike.

thanks everyone

will inform if i get it running and hopefully pass my test tomorrow.
 

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i dropped the engine last night and tapped more threads into the tensioner bolt hole. and now it locks tight! what a relief! im a little worn out having dropped the engine twice in as many days, but its all good now. and im all the more aquainted with my bike.

thanks everyone

will inform if i get it running and hopefully pass my test tomorrow.


That's terrific! Now that is fixed you have one less thing to worry about at your test. And the confidence you gained by fixing the bike will stand you in good stead as well. Good Luck!
 
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