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Manual cam chain tensioner adjustment (MCCT)

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For those of you who run manual cam chain tensioners - I'm wondering how you guys recommend setting them properly?  Between the how-to's I've read on Thumper Talk, Big Bore Thumpers, and manufacturer installation instructions...there are two main methods that people recommend setting them:

1.)  Set the engine to TDC.  Screw the tensioner in with your fingers until you can feel resistance from the cam chain.  Then, rotate the motor forwards (by hand), while screwing the tensioner in (with fingers) until you feel the cam chain drag against the cam chain guide. Then back it out 1/4 turn.  Lock it down and you're good to go.

2.)  Set the engine to TDC.  Screw the tensioner in until the tensioner just touches the chain guide (finger tight only).  Then, start the engine and let it idle.  While the engine is idling, back the tensioner out until you hear a distinctive rattle from the cam chain/guide.  Tighten the tensioner JUST until the rattle goes away.  Lock it down and you're good to go.

Which method is correct/safest?  Is the end result of the adjustment the same for both?

 

Referenced links:

http://www.thumpertalk.com/topic/552694-mcct-install-guide-and-why-one-is-recommended/

http://www.bigborethumpers.com/installtensioner.html

http://www.aperaceparts.com/tech/tensioners.html

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LOL, depends. I like the 'can of washers' (running engine #2) method. Problem is, many people simply are unable to discern it.

The next best mthod is with the cam lobes at 2 and 10 o'clock. Tightened till resistance is just felt. Grab the chain, confirm it 'feels tight'. Rotate the engine 720 degrees (back to TDC/ cams at 2 and 10) and confirm it is the same. Do not tighten the tenshioner more. It is very possible to overtighten it with just your fingers. All you want to do is remove the slack.

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Just remember to snug up the lock nut on that thing because if it loosens up while riding it could roach the engine.

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LOL, depends. I like the 'can of washers' (running engine #2) method. Problem is, many people simply are unable to discern it.

The next best mthod is with the cam lobes at 2 and 10 o'clock. Tightened till resistance is just felt. Grab the chain, confirm it 'feels tight'. Rotate the engine 720 degrees (back to TDC/ cams at 2 and 10) and confirm it is the same. Do not tighten the tenshioner more. It is very possible to overtighten it with just your fingers. All you want to do is remove the slack.

 

I could see how many people - even myself, might not be able to discern the sound of the cam chain being too loose...especially since the 450 thumpers have a noisey top-end anyways - IMO.  Thanks for the input William - appreciate it.

 

Just remember to snug up the lock nut on that thing because if it loosens up while riding it could roach the engine.

 

Absolutely!

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LOL, depends. I like the 'can of washers' (running engine #2) method. Problem is, many people simply are unable to discern it.

The next best mthod is with the cam lobes at 2 and 10 o'clock. Tightened till resistance is just felt. Grab the chain, confirm it 'feels tight'. Rotate the engine 720 degrees (back to TDC/ cams at 2 and 10) and confirm it is the same. Do not tighten the tenshioner more. It is very possible to overtighten it with just your fingers. All you want to do is remove the slack.

Bumped this old thread because I hear a noise occasionally from my timing chain.

Before making valve shim adjustments, I measured the distance from the lock nut to the end of the screw (alen, not hex head), and set it back to the same dimension ~3/8" IIRC.

I am going to try the engine running method and loosen the tensioner up some then go back in.

I think the chain may have too much tension on it now.

Just curious if anyone has any more input or additional links to simplify the job?

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