Carrera tensioner upgrade

[Clark Griswald]

I'm heading out to the garage now to put carrera tensioners in my '77. I've read the tech article and a few posts about bad tensioners.

Seems wise to test the tensioners before installing. I press on the pistons and find the spring tension is solid. Should I do anything else to test these puppies before they go in?

Anyone have tips in addition to the tech article?

Okay, start the timer. I moving now.

[rstoll]

Put 'em in and don't read any more articles.

[Early_S_Man]

You ARE replacing the chain ramps at the same time, RIGHT, Chuck?

[Doug Zielke]

When you press on the plungers, you really can't tell anything as the "safety pin" is still inserted in the tensioner body. And you don't pull that out until you are ready to button up the cases.

The tension is generated two ways: A internal spring and oil pressure acting on a piston, supplied from the motor's oil gallery.

When you first start the motor with the new tensioners installed, you may hear a bit of rattling. It *should* stop after the tensioners pump themselves up. If the noise continues (unlikely), then there may be something wrong with them.

Don't worry. Just have fun.

[makaio]

Chuck i just read the article and then did it. You have much more Porsche wrenching experience than I, so it should be a breaze for you.

The hardest part for me, was removing the distributor, and installing the left side oil line.

[Clark Griswald]

Actually I bought the setup used. So the pins have already been pulled and the tensioners have residual oil in them.

I am anticipating that I need to re-compress these to get them installed.

Warren you are going to lecture me on this one but I decided to open it up and have a look at the chain ramps before deciding if need to replace them.

I've been out cleaning and inspecting the parts. Everything looks to be in order except for a rusty cad plated line. Hopefully it holds oil so I can get through this, but it will be replaced as soon as I can get a new part.

[Clark Griswald]

The tensioners are in and the covers are on. Tomorrow I'll put the rest of it back. I am going to POR-15 the engine sheet metal while I have it out.

Everything went smoothly. I used a big C clamp to compress the new tensioners so they could slip on. I had one cover bolt that was very tight, I was sure it would snap off. So I heated the base metal with a torch and it came right out.

One thing has me a bit concerned; the passenger side piston sits cleanly on the idler arm. The driver side hangs off the idler arm by about 1/3 of its diameter.

There is no way the piston would slide off the idler but I just doesn't look right. Here is a picture, but it is kinda hard to see.



I know there are two different types of idler arms. The early ones need to be spaced out for the upgrade. But my car is a '77 so I don't think it needs the spacers.

Here is Wayne's picture from the tech article:



Again it is hard to see from the camera angle, but it appears that the piston on Wayne's install hangs off the idler as well.

I have an extra set of idlers which are the later style, so I can swap it out if needed. But I don't think it is required.

What do you guys think?

[911pcars]

If your idler arms are pre'81, then you have the early versions and you will need either the spacers or the later arms.

Since you have them, I suggest installing the late arms now. BA says the narrow-bushing arms contribute to tensioner failure due to binding.

Obviously, you have compressed these already and confirmed they're okay. However, if these were new tensioners, I would suggest temporarily installing the oil lines w/o the covers, then cranking the engine to build oil pressure and verify they don't go soft.

BTW, from your camera angle, it looks like you're doing this w/the muffler installed. I know it's a little more work, but access is easier w/o it and recommended if you're going to replace the idler arms. You want to make sure the cams/chains don't move when you do this.

Sherwood Lee
http://members.rennlist.org/911pcars
www.seinesystems.com

[Clark Griswald]

I think I will try swapping that idler and see if the other one looks better. However, the passenger side one looked just fine.

The muffler is out, it would be a bear with that muffler in place.

Warren you are probably right and I should replace the chain ramps as a matter of course. But they look fine and I don't have replacements in hand. I may live to regret it but onward I go.

[BK911]

Clark!

Might be a good time to check/adjust the cam timing as well.

Good luck!
BK

[Clark Griswald]

Apparently the night shift fixed the problem while I slept. When I pulled the cam cover the piston was nicely positioned on the idler.

It seems that when I first put the tensioner on (in the dark with only a trouble light to guide my way) it was not fully seated. I realize this now because when I first installed the cam cover I had to tap it on. I attributed the resistance to the rubber O ring seal friction, but it was more than that.

So when I Installed the cover, the tensioner seated properly but I couldn't see it. Of course the tensioner retaining nut was loose, so it's a good thing I pulled the cover back off to check.

Re-timing the cam would seem like a good idea. Unfortunately I don't have the tools to do this. That will have to be deferred until I rebuild this puppy (maybe another 100k miles).

Anyway the tensioners where completed yesterday, now I am painting the engine sheet metal and rear engine mount. Seems I always spend more time cleaning and painting than I do wrenching.