engine and drivetrain Cam Chain Tensioner

[ndog]

is anyone running this on a street car

http://www.iemotorsport.com/bmw/2002-engine/02tensionmech.html

thanks for any info

nate

[TobyB]

Never needed that- even on the race car...

 

But it's not a bad idea for a race car.

 

t

[Harv]

I have one on my motor but I have yet to fire it so..... I can say the one I got is too long and the finish of the internal rod is poor. My plan was to shorten it in a lathe at my friends shop.

Then I heard on the web that it has a problem with leaking oil at the adjustment.

I can't remember who made it but someone makes one with an internal o ring and it uses the stock push rod. I have yet to install it but it's laying on the rad support waiting.

My guess is that it will require regular adjustment.

John

Edited December 10, 2013 by Harv

[FB73tii]

 I can say the one I got is too long and the finish of the internal rod is poor. My plan was to shorten it in a lathe at my friends shop.

Then I heard on the web that it has a problem with leaking oil at the adjustment.

 

Yes, the rod is a bit long but I ran into a different problem on my race engine--the body is too long if you use really thick aftermarket head gasket. To make my 11.5:1 pistons work it turned out I would either need to flycut the piston valve relief pockets (will do next year) or raise the head with a 0.120" MLS head gasket (which I did this Fall to be able to run the car) for sufficient V/P clearance. This pulls the timing chain way tight, I had to bend the rubber -coated timing guide ear just to relax tension enough. Then every time I put in the mechanical adjuster it got too tight. I shortened the rod portion twice to no effect. Then I realized the outer threaded body is longer than stock and that was pushing the plunger piston in when tightening. I ended up just putting in an oil pan plug and that worked perfect for now.

 

I did two things to avoid oil weeping from the adjuster threads, and ran the engine about 2 hours with no oil leaks before V/P contact killed it this summer. (1) coat the threads with a non-setting sealer like Hylomar; and (2) drill holes in the bottom of the aluminum pocket that holds oil for the stock hydraulic timing chain tensionser. Perry Genova gave me this tip, but it means you need a new front cover if you ever go back to the stock tensioner.

 

I recall another way to accomplish the same effect (mechanical tensioning) for less $$ (but more hassle) is to just remove the spring from the stock tensioner and pack washers of the appropriate diameter and thickness in its place until it provides the tension you want. Would require some very thin washers to get perfect, so not only can you index your spark plugs and safety-wire bolts holes, you can index your chain tensioner!

Edited December 10, 2013 by FB73tii

[bnam]

My car had one on it when I first got it.  Ran it that way for about a 1000miles.  Then switched to regular tensioner.  Avail for sale if you want it.

B