Wayne, In 1995, you wrote the following in the tech forum regarding the pre-priming of the new tensioners before installation. I was wondering if anything has changed since then: ie: do they need to be pre-primed or not. Thanks

Thanks for the comments / feedback. These tensioners are one of the most mis-understood items on these complicated 911s. Firstly, they are not oil-pressurized tensioners, they are oil-dampened, which makes a huge difference. That means they are spring-loaded and then oil filled to dampen them like a shock absorber during operation. I believe that the oil dampening reduces the spring-back effect of the natural spring inside and helps to keep tension on the chain and prevent "bouncing" of the chain tensioner against the wheel.

That said, in my two books, I do recommend priming them in a bowl of oil. I cannot remember what the "factory" recommends, but I do remember that the information the factory has put out on these is not 100% clear. Simply putting them into the engine and letting them fill up with oil by themselves should also be adequate too, as they have bleed valves in the tensioner that will / should bleed the pressure off. I would let the engine idle for several minutes before revving or driving it to make sure they are fully bled.

The bottomline is that you're not likely to have instant chain tensioner failure even if they are completely devoid of oil. If they are not charged / fed with oil, then I would suffice they would wear out a lot faster and probably cause other problems with the chain wheel. My conclusion is that either method would probably be okay, but I prefer to "prime" them "just in case."



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The priming discussion goes both ways. I have done it both ways myself and not had an issue. If you want to be safe, prime them and be done with it.



- Nick