Cam Chain tensioner install

5 replies to this topic
  • jroon

Posted October 04, 2009 - 05:36 AM


Hi folks, been awhile since I posted, I have been working on my old Husky but now its time to finish the 426. I had the motor redone by some students at the College where I work and they apparently forgot to install the dowels for the head, no big deal, I removed the cams and head and installed the dowels and today was gonna be the big final assembly day. Now, as I read my manual I see I am supposed to fabricate a "Cam chain tensioner stopper plate" Holy cow, I wasn't planning on that...Do I need to? Is there any tricks to avoid it?
Also, the "I" mark on the flywheel for timing looks like more of an "H", should I use that when setting up the cam sprockets? Before diassembly I checked and it seemed like one of the dots on the exhaust cam sprocket was about a tooth out from being lined up horizontally with the top of the head(as per the manual) This was probably not cool right? Any other pieces of advice? I would like to have it ready for a Hare Scambles next Sunday(PS The motor is out of the frame, any antifreeze bleeding procedures I should worry about?
Thanks for your time everybody!
If anybody cares I have a good story about riding a 1985 Husky CR500 in an ultra tight Hare Scrambles last weekend. My God, never again!

  • grayracer513

Posted October 04, 2009 - 08:15 AM


On the timing mark, the "H" is for ignition timing. Turn the engine a little farther forward and you'll find another, single mark that is TDC.

On the tensioner, you should find that if you turn the internal shaft to the right until it stops, it will stay there on it's own. Then you can install it without using the plate. Once it's in place and tightened down, you turn the shaft slightly to the left, and the spring takes over and runs the tensioner plunger in.

  • jroon

Posted October 04, 2009 - 08:26 AM


Grayracer! Thank you very much! I am heading out to the garage RIGHT now!

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  • jroon

Posted October 04, 2009 - 02:37 PM


OK, top end assembled, motor in frame, cooling system complete. Now, what is probably a silly question. I have found my TDC, my cams are splayed out and the marks aligned with the top of the head, BUT, how do I know on which TDC the ignition will fire on? Now I am worried, there is no mention of checking your spark timing anywhere. Does it spark on the compression stroke as well as the exhaust stroke?

  • grayracer513

Posted October 04, 2009 - 06:40 PM


The ignition is triggered by a sensor coil on the crank, and fires every revolution, regardless of whether it's the compression or exhaust stroke.

  • jroon

Posted October 04, 2009 - 06:48 PM


Whew! Thanks again, have a good night.

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