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mark houghton mark houghton is offline
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Join Date: Jul 2008
Location: Central Washington State
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Quote:
Originally Posted by Flieger View Post
All Porsche cam chain tensioners are hydraulic. They all use oil to dampen the spring. The spring is what does the actual tensioning. The difference is in where the oil comes from. Some just have a one-time fill of oil while Carrera style get a constant feed of pressurized oil.

"Mechanical" tensioners commonly refer to the solid metal ones used for setting timing.

The safetry collars only work on non-pressure fed tensioners. There is a mod that involves cutting a length of rod to fit inside the pressure-fed ones so that it acts as an internal stop. "Jerry Woods mod" would be a good term for searching.
So true. I guess the reason that the "mechanical" (misnomer) tensioners...although they are sealed hydraulic/spring units...is that when the seal fails and the oil leaks out, then all you have is the tension of the internal spring, which isn't sufficient to keep the proper tension. I guess that's the attraction of the pressure fed system.
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Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 11-07-2010, 03:10 PM
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