Big problem - tensioner clicking??

[natedees]

All,

I just got finished with a big overhaul on my 82 GS550L which included rebuilding the cam chain tensioner. I think I put it back together right based on instructions posted here, but when I went to put it back on the bike, I had to REALLY shove it back in it's hole to get it to fit all of the way in. I must have been moving something...

And then, the instructions say to loosen the set screw and release the pushrod, allowing it to pop into whatever it must be up against inside the engine - well, with mine, it was already up against something it felt like, so it never popped when i released it - I just turned it out by the amount the instructions said, a 1/2 or 1/4 turn (a clearance I had tested before) and figured it would be released and work fine.

Today - everything back together, fired it up, and I hear a clicking noise. I believe that tensioner might not be working right. When the bike is off, should I be able to turn the knob against the spring? When the bike is on, I can turn the knob, and the clicking gets more pronounced, like I am pushing the pushrod against the chain or whatever it is actually touching. I dont know what to do with it - I am afraid to ride it, and I can't get it to a shop any other way. Please help!

Thanks in advance.

 

[mark]

Before you install the tensioner, the plunger should be pushed into the tensioner and held with the lock-nut. It should not have to be "shoved" or forced into the block at all. Then, when you release the lock-nut, the tensioner will automatically take up the slack. I can't think of why you might have had to "force" yours.

I think you're right not to start the bike until you've installed your tensioner correctly. I'd take it off, check it and re-install.

One thing you can do to check for proper operation is to back your engine crankshaft anti-clockwise a bit (just a tad) so that the tension in your cam chain is on the "back" side. Install the tensioner and then rotate your crankshaft in the proper direction. You should be able to see the knurled knob on your tensioner take up the slack if its working properly.

You can turn the knurled knob on the tensioner when the bike is off.

 

[natedees]

Hi Mark - I actually did have the plunger pushed in and held with the lock nut. I don't understand why it had to be shoved in either. Can you tell me how to perform the test you suggested - "back the engine crankshaft anti-clockwise a bit"? I'm not sure how i would do this. Thanks.

 

[mark]

Hi Mark - I actually did have the plunger pushed in and held with the lock nut. I don't understand why it had to be shoved in either. Can you tell me how to perform the test you suggested - "back the engine crankshaft anti-clockwise a bit"? I'm not sure how i would do this. Thanks.

If you take off the engine cover on the lower right side of your motor, there's a hex nut that is used to turn the crank. If you back it up anti-clockwise (maybe 1/8 of a turn) the cam chain tension will move to the back side of your cam chain. This test can only be done when you are installing the tensioner, not after its taken up the slack.

But that's really not the important thing at this point. You have to figure out why you had to force your tensioner on first before you do anything else. I really don't know why that might be.

Maybe wait to see what somone else has to say, but I'd take it apart and try to figure that out first................

 

[49er]

What was the extent of your engine overhaul? Did you replace the cam chain? If so, are you sure that you fitted the correct length chain for your model?
If you have correctly compressed the plunger and locked it in position before attempting to fit the cam chain tensioner, the likely causes of the tightness are an overtight camshaft chain or an incorrectly fitted/ wrong chain guide.
Check this link on the Bikebandit site to confirm your cam chain assembly and components are correct.
http://houseofmotorcycles.bikebandi...el_dept_id~988021~model_dept_name~GS550LZ.asp

 

[natedees]

Actually, I didn't replace the cam chain - major overhaul for me was only putting in a new stator, and replacing the cam cover gasket because of oil leaks. (and rebuilding the tensioner.) That's why I dont understand, like Mark, what changed between when I took the tensioner out and put it back. I wish I knew better how it worked, what the plunger hits, because maybe I put it back together wrong even following the instructions...

 

[mark]

Actually, I didn't replace the cam chain - major overhaul for me was only putting in a new stator, and replacing the top cylinder gasket because of oil leaks. (and rebuilding the tensioner.) That's why I dont understand, like Mark, what changed between when I took the tensioner out and put it back. I wish I knew better how it worked, what the plunger hits, because maybe I put it back together wrong even following the instructions...

I'm just brainstorming here. But when you push the plunger into the tensioner, you have to twist the knurled knob out in order to make room for the plunger to get back far enough into the tensioner. Did you do that?

 

[natedees]

Well, I think so - I had to twist the knurled knob out to push the plunger into the tensioner unit (as far as it would go), and then locked the plunger in with the setscrew. So at this point the knob was locked in its position also. Then I put it on the bike, but still there wasn't enough clearance - I am absolutely sure that the plunger was in as far as it can go. And whatever I was pushing against finally gave inside the engine - it's just that then I feel that the end of the plunger was resting against whatever I had pushed inward, and so when I released it, it did not "pop" out as expected. I just turned the setscrew out enough to release it by what I had tested, and then tightened the locknut.

When the bike is on, I can turn the unit counter clockwise, and it seems like the plunger is pushing on something that makes a clicking noise. Is that normal.

And when the bike is off, It seems like I can't turn it at all, which would make me think that the plunger is pushed all the way in the tensioner unit.

I've got to get this right after going this far. Thanks for your help.

 

[mark]

Yeah, somehow you're all jammed up. The knob should turn when the bike is off. I don't see any other option for you other than taking it all apart and trying to see what the heck happened.

 

[drejal]

bump?

sorry to resurrect such an old thread, but I just had the tensioner out of my 79 550L so that I could pull out and test the starter. (apparently needs the brushes replaced)

I cleaned the tensioner well, re-installed properly (I believe), and now it's making this same "clicking" rather loudly when I started it. I didn't have any trouble re-installing, like natedees had.

I can't see if "natedees" is still an active member, so I have no idea if he was able to solve the problem.

I actually did a few things while I was working on the bike in addition to the starter and cam tensioner. I also replaced the clutch springs and the gasket, and also turned my pilot air screws a little richer according to my plug readings. I don't think any of those can cause a rattling or clicking while running the engine, but figured I'd include them just in case.

any help would be appreciated, would rather not run the bike in this condition!

 

[tkent02]

Any chance you turned the crankshaft while the tensioner was not installed???
The valve spring's tension will cause the cams to POP to the next position as the chain skips a few sprocket teeth. Then if you ran the engine there could be all kinds of expensive noises coming out depending on how far the cam timing is off.

 

[drejal]

hmmmm....could pulling the starter out, and reinstalling have done that?

I never turned anything or hit the starter button / kick starter to move the crankshaft.

 

[tkent02]

No, you should be OK.

 

[drejal]

ok....took the carbs back off to make getting to the tensioner a little easier, pulled the plugs, and am turning the engine manually. I can hear something click about once every revolution. i can actually see the tensioner jump also. It's like there is a kink in the cam chain? has that been known to happen? or stumbled onto something else?

I'm getting a little beyond my scope of knowledge here. I understand the function of the timing chain, I just have no earthly idea what i've stumbled into!

thanks for the help so far, it's truly appreciated.

andre

 

[tkent02]

ok....took the carbs back off to make getting to the tensioner a little easier, pulled the plugs, and am turning the engine manually. I can hear something click about once every revolution. i can actually see the tensioner jump also. It's like there is a kink in the cam chain? has that been known to happen? or stumbled onto something else?

I'm getting a little beyond my scope of knowledge here. I understand the function of the timing chain, I just have no earthly idea what i've stumbled into!

thanks for the help so far, it's truly appreciated.

andre

Stop turning the crank, read this:

Any chance you turned the crankshaft while the tensioner was not installed???
The valve spring's tension will cause the cams to POP to the next position as the chain skips a few sprocket teeth. Then if you ran the engine there could be all kinds of expensive noises coming out depending on how far the cam timing is out.

Check the timing marks on the crank and the marks on the cam, do not turn the crank unless the cam timing is correct and the tensioner is in place.

That click is the cam popping over to the next unsprung position.

OK, as the cam turns, the valve is pushed down against it's spring. As tension builds, the cam sprocket wants to turn to relieve this spring pressure, since the chain is not tight it can, by slipping a few teeth. POP or CLICK, whatever it sounds like. The next noise is the valves hitting the pistons, since the cam timing is no longer correct, valves are open when the piston is up, it doesn't fit that way.

Get your cam timing back to the right place, see if it rotates freely, then check the compression to see if you bent any valves.

 

[drejal]

one more note...

I found that if I lock the plunger on the chain tensioner down, as though it's a manual tensioner, the engine rotated smoothly. Started it again, and it's fine.

SO...unless someone knows why this might be a bad idea, I'm just gonna go with it!ray:

dre

 

[drejal]

Stop turning the crank, read this:

Any chance you turned the crankshaft while the tensioner was not installed???
The valve spring's tension will cause the cams to POP to the next position as the chain skips a few sprocket teeth. Then if you ran the engine there could be all kinds of expensive noises coming out depending on how far the cam timing is out.

Check the timing marks on the crank and the marks on the cam, do not turn the crank unless the cam timing is correct and the tensioner is in place.

That click is the cam popping over to the next unsprung position.

wow, I just reread that and realized how bad it sounded. I never rotated the crank with the tensioner out!

thanks for your concern!

 

[BassCliff]

Hi Mr. drejal,

Here is some wisdom that I've collected from this forum. It might help you.

Cam Chain Tensioner Repair
Reset Cam Chain Tensioner


Thank you for your indulgence,

BassCliff

 

[Guest]

Don't run the bike with the tensioner locked down. Check the links that BassCliff gave you and put it in the right way.

 

[drejal]

Thanks for your guidance! It was because of these two guides that I decided to tackle cleaning the tensioner. (well, frankly, i consult basscliff's site and GSR before tackling any project!)

The confusing part is that the one on my 550L is a much simpler design. Two mounting bolts, allen head bolt with locking nut, pushrod with spring. So I have to skip over a lot of the "turn the knob" and "watch the knob when you..." because mine has no knob!

I'll be pulling the timing cover off to inspect what is going on with the cam chain. I figure it's better to actually SEE what is up with the chain rather than guess. It'll be a few days before I really can set aside time for the job, but I'll report back so hopefully the next guy with this problem will find a solution.

Again, thank you all for the help!