cam chain tensioners

Farm Shop · Post by **Farm Shop** » Thu Feb 12, 2015 3:42 pm

So in the boxes of parts that my 67 scrambler came in there are 2 cam chain tensioners. One is the early style with the wider mount and one is the narrower which I need.

Someone I can see replaced the whole arm on the narrow one so it had a good wheel. But the arm is from an early style wider tensioner and it just doesn't look right.....

How different were the arm Assembly's?

The second pic shows the narrow style tensioner with the plunger compressed all the way

Fs

OldScrambler · Post by **OldScrambler** » Thu Feb 12, 2015 9:56 pm

As long as the arm and wheel are straight and centered, and the arm rotates freely on the pin............it should work. If the metal is sharply bent to fit, or the pivot pin is cramped, it could bend to the side under pressure from a down-shift. That would likely cause trouble.

Farm Shop · Post by **Farm Shop** » Thu Feb 12, 2015 10:08 pm

The arm moves freely but it seems like the arm doesn't have the range of motion as it should?

I started looking at pictures of other tensioner and it almost looks like the later ones had somewhat of a curved arm?

OldScrambler · Post by **OldScrambler** » Fri Feb 13, 2015 9:41 pm

The arm needs to rotate from a little less than pictured to almost perpendicular. It needs to swing easily so the spring tension will keep it in constant contact with the chain when it relaxes ........slowing down with clutch engaged.

Farm Shop · Post by **Farm Shop** » Sat Feb 14, 2015 10:36 am

Thanks for the replys oldscrambler.

I actually was able to get my hands on a good used one off eBay last night. The one I have might work but I don't want to trash the motor I just rebuilt from the crank up over a 40 dollar part.

When I get the new one in the mail I'll post a picture of how they are different.

Fs

OldScrambler · Post by **OldScrambler** » Sun Feb 15, 2015 5:42 pm

Wise choice....................and the pic will be educational for others.

Mark your calendar..........June 5-6-7............Vintage racing (AHRMA) and Rocker Box Moto-Fest at Road America.

LOUD MOUSE · Post by **LOUD MOUSE** » Sun Feb 15, 2015 7:57 pm

OPS!
When you tighten the Shaft Setting Bolt that arm is LOCKED IN PLACE and doesn't move. ........lm

OldScrambler wrote:The arm needs to rotate from a little less than pictured to almost perpendicular. It needs to swing easily so the spring tension will keep it in constant contact with the chain when it relaxes ........slowing down with clutch engaged.