mpiffaretti

Guys good afternoon, quick question, how can I tell if my SC has had the Carrera tensioner upgrade? if somebody can post a picture with the "before" and "After" it would be great. Lastly, if needed to be replaced, how much should the cost be for labor alone?
thanks!

obscene

you'll see an oil line coming out of each of your tensioner covers if the carrera tensioners have been installed

psychoideas

^^^^
what he said!

psychoideas

^^^

mpiffaretti

perfect, thank you. I just checked and I don't have that upgrade. Is it absolutely necessary in your opinion? I read some many contradicting posts in which some will swear by Mechanical tensioners, and some by their oil fed ones. Both sides claim both tensioners fail at some point. What's the definite answer?

obscene

the oil fed tensioners are less likely to fail, but not 100% immune to failure. I don't have the link handy, but the safest bet is to use the oil fed tensioners with a piece of metal tube inserted in the base of the tensioner which prevents it from collapsing completely in the event of a failure.

mpiffaretti

I've seen those. I think they are called Collars made of aluminum that go around the Piston.

obscene

the collars are only compatible with the non-oil fed tensioners. they are a much debated 'fix' that clamp to the piston and prevent it from collapsing. I think people worry that pieces could break off and cause futher damage.

the inserts I was referencing are better described here: http://911t.pca.org/tech_tips/limiti..._pressure_.htm

autobonrun

Pressure fed tensioners are universally accepted as the optimum solution. I chose the less expensive option of adding the mechanical stops 30 years ago for about $60 in material. I think the pressure upgrade now is over $1000 parts and labor. Back then it was around $600. If I do have a tensioner failure or have to go in that area of the engine, I'll go back with mechanical tensioners and new collars. So far I'm at 213k miles and have not had to open engine. You'll have to decide which gives you peace of mind. My comfort level is fine with just the collars and mechanicals, but I understand those that go the extra step.

Here's good reading on the subject by Roland Kunz. It's a thirteen year old post but the details remain valid. One guy interrupted intelligent conversation but you can ignore that part.

http://www.early911sregistry.org/for...p/t-31886.html