Initial adjustment of mechanical cam tensioner

smt71targa · 05-20-2011, 01:13 PM

I am doing a top end refresh on a 2.2 liter and it had mechanical tensioners in it. I want to put them back in, but need some help on setting up the initial tension. I am aware of the draw backs of the mechanical tensioners. The reason I decided to stay with the mechanical tensioners is because of the intended use of the car, it will be a low mile car, only driven about 5000 miles a year. I don't know how many miles were on the engine, it ran well (just leaked oil like crazy) The chains and sprockets were in good shape, no unusual wear marks. So who can give me some advice on how to set the tension? Thanks in advance. (please no lectures on using the adjusters)

Flat6pac · 05-20-2011, 06:11 PM

With the mechanicals, you decide how tight you want it because once youre running it will be looser than you set it. Thats why the hydraulics work.
Bruce

chris_seven · 05-20-2011, 11:39 PM

Quote:

Originally Posted by Henry Schmidt

Remember that as the engine heats up the chains get tighter, so the chains when cold will seem loose.
I use the thumb nail method.
Turn the engine over in reverse. That will put maximum slack in the chain. Now adjust the tensioner so you can lift the chain off the chain rail (with your thumb nail) 1/2 inch. Now rotate the engine clockwise one turn. Now go back one turn and check again. If you can still lift the chain 1/2 inch you're good to go.
Remember loose is better than too tight. Too tight when cold will cause damage when hot.
When you start the engine if you hear a chain rattle it may be too loose, but don't worry it won't fail. If it rattles when it's hot it's way too loose.

Henry posted this some while ago and I have not seen anything better since.

smt71targa · 05-21-2011, 05:24 AM

Thanks Chris, I think I saw this post earlier, and will probably go with that. I just figured porsche mechanics being as anal as they are, and since they run these in race engines, that someone would have a by the numbers precision adjustment technique.

Flieger · Flieger's Garage

Are you sure the factory used to use these in race engines?