Chain Tensioner Question...

Glen Pettigrew · 06-09-2010, 04:47 PM

1974 911S 2.7 (completely stock, or so I thought)

What kind of tensioners are these?

Removed Chain box covers to replace seals and install pressure fed
tensioners and this is what was installed for tensioners on both sides:

These appear to be purely mechanical tensioners and are adjusted with
an allen wrench. No springs at all.

Thanks...
Glen

yelcab1 · 06-09-2010, 05:08 PM

Fully mechanical tensioner, used for racing engine a lot.

silverc4s · silverc4s's Garage

Solid, mechanical tensioners are generally not a good idea on a street car. In order to work properly, they will need adjustment at regular intervals, as the chains wear & stretch.
Carrera tensioners are the best solution for most of us.

Glen Pettigrew · 06-09-2010, 06:35 PM

yelcab1,
Thanks much for the quick answer!
Bill,
Thank-you for your answer & advice.

Can't imagine why these were put on the car. The owner of
the car that this motor came from never raced it.
Anyway, as seen in the photos, I have already removed them
and am putting on the pressure fed tensioners. I guess I
can keep them as a tool when working on tensioners and/or
cam timing etc.

Thanks again to both of you..

Glen Pettigrew

DanielDudley · 06-10-2010, 02:27 PM

People use them because the can not fail, and they are fairly inexpensive. I found a set on my 78 SC as well. Carrera tensioners now.

DanielDudley · 06-10-2010, 02:32 PM

BTW, I am not advocating them in any way. The biggest downside IMO is that they cannot compensate for engine expansion during warm up and cool down. I would expect that if they were too tight they would cause rapid chain wear or stretch, which is similar. Set up properly, I would expect them to be slightly sloppy when dead cold.

But I am not a doctor.