Cam Chain Noise

[Morgan]

Hi all,
I recently completed the valve adjustment at 60,000 miles. I replaced the original spring loaded cam chain tensioner with a manual one. The instructions were to tighten it down until it contacts the guide and then turn a single quarter turn. I did this. With the engine cover off I manually turned the engine over a few times check for slack and found almost none. Put it all back together and started it up. Everything was fine, but I did hear a bit of chain rattle. I gave the tensioner another small turn and the noise stopped. I have driven about 1000 miles and everything feels fine but I have noticed that the chain noise has come back, but only when the engine is warm. I tried tightening the tensioner another quarter turn but the noise didn’t stop this time. I’m reluctant to keep tightening lest I break something. What should I be checking to figure out why the chain is still loose. Or does the S10 just makes some chain noise? I can’t remember what is sounded like before did the valve job. The odd thing is there is no noise when the engine is cold and first starts up. It’s only after I have ridden for awhile. Ideas?

 

[~TABASCO~]

Its sounds to me that it's still loose.... NO pun intended.... LOL

The way I have found that tends to work really well is this.........

-Back off the jam nut
-take off the service cover for the crank shaft
-Manually tighten the MMCT with a socket BY HAND while spinning over the crank with a ratchet.
(you will find that as the crank goes around in a circle the chain will tighten at a certain spot each revolution of the 360*)
(keep doing this with your hands until you can't turn the socket on the MMCT any longer by hand)
-At this point I mark 12:00 position. (make note)
-Now you put the service cover back on the crank hole
-With the GRAVES MCCT I can then manually turn the screw out approximately 1.0-1.5 turns out (and your good)
-If you dont have a Graves unit, you will have to do as fallows (because of the thread pitch)

-Start the motor and loosen the MCCT slowly until you hear a slight chain chatter...
-Turn motor off
-Mark the 12:00 again in a different color (I typically use red for loose / black is tight)
-So now you have two marks, loose and tight.
-Start the motor again.

-What I do is tighten the screw and loosen the screw several times and listing to the motor very carefully.
-You will hear a 'whine' when it's tight and the chain chatter when its loose.
-Once I know the two spots (and checking them several times just to make sure)
-I split the difference and tighten the jam nut

Your done

 

[Morgan]

Thanks for the detailed reply. Just a few points of clarification. When you say “by hand” you mean with a wrench or ratchet, not my fingers. Correct? The marks are made on the MMCT threads?

 

[~TABASCO~]

Thanks for the detailed reply. Just a few points of clarification. When you say “by hand” you mean with a wrench or ratchet, not my fingers. Correct? The marks are made on the MMCT threads?

Turn the socket on the MCCT by hand (literally). No wrench or ratchet needed as you spin the crank with a ratchet.... Keep pressure on the socket (tighten) as you spin the crank. As you spin the crank your will feel the socket slightly tighten each time the crank spins 360*..... Keep doing this whole process until you spin the crank with a ratchet and you can no longer tighten the MCCT with your fingers (using the socket).

Your finger tips are sensitive. You will be able to feel the small amount of movement holding / tighten the socket. DO NOT USE any wrench for ratchet on tightening the MCCT at this point... Now it's down to the "fine tune"..............

Im very particular.... When I do all these steps I typically do them over and over probably five times to make SURE everything is as accurate as possible.

I dont always come back and read post...... If you have more questions PM me or post the question and PM to tell me there is another question, otherwise I would probably not ever see or answer the next question....

Thanks