bds1

I installed my chain tensioner upgrade kit (OEM porsche) into my 1980 SC over the winter. I had only run it at idle and all seemed quiet and well.
Last nite I finally took it for a spin and heard a nasty noise on engine speed change. I assume that since I had no noise prior to upgrade, the noise is due to my "upgrade".

Has anyone had a simular problem? IS the oil pressure stretching my chain so that it hits the case. When I get it apart I'll probably use 50 psi air pressure to expand the tensioner and check clearances, will this damage anything?

My oil pressure is normal. I guess I'll start by loosing lines and make sure oil squirts out with vengence . Luckily this is not a major tear down....yet?

Bruce

bds1

The evil noise comes after the engine is warm. Quiet and tight at startup. There was no noise prior to upgrade. I use 20-50 oil. time to get the wrench!

emcon5

I installed pressure-fed tensioners just after Thanksgiving of last year. One of the new tensioners in the kit was good, one wasn't. The replacement for the bad one was bad. The replacement for the replacement was also bad. I currently am running a good used tensioner my wrench had laying around.

All the bad tensioners would leak oil out of the pressure relief valve with the pressure of a small oil can (small thumb pump). <a href="http://forums.pelicanparts.com/showthread.php?s=&threadid=53565" target="_blank">More info on my tensioner saga here.</a>

There is a thread on Pelican with a instalation proceedure that came from on of Pelican's suppliers, with instructions for removing air from them by submerging them in oil before installing. I am not sure I buy it, but you can see the somewhat heated discussion here:

<a href="http://forums.pelicanparts.com/showthread.php?s=&threadid=55326" target="_blank">http://forums.pelicanparts.com/showthread.php?s=&threadid=55326</a>

bds1

Thanks for the post! I applied air to the tensioner .... I expected it to hold pressure. Neither left or right holds pressure. My gut tells me I can't have two bad (OEM) tensioners. I will read the post on pelican. I observed a very large gap between the tensioner and the idler. I know when I bought the tensioners there was question on a "spacer" I may need. It was deemed that I didn't need them ....but I have about .1 inch (100 mils) between the idler and the tensioner. I assume that the racket may be this, See attached pix.

<a href="http://boards.rennlist.com/upload/tensioner.jpg" target="_blank">http://boards.rennlist.com/upload/tensioner.jpg</a>

bds1

After reading the pelicanparts news thread on pressure fed tensioners I would NEVER put one set in. I would of stayed with OEM spring fed ones. I don;t like the fact how if they fail you loose needed oil PRESSURE!

Bill Gregory

1980 and earlier 911's need a spacer, part number 930.105.513.00 between the tensioner and engine. It goes in the spot you identified as "gap" in your picture. This is documented in the Porsche Parts and Technical Reference Catalog (best $12 you'll spend on your 911), in Technical Bulletin 2, "Hydraulic Tensioners". They are not part of the Porsche tensioner upgrade kit.

Paul Brewer

bds1,
Oil fed tensioners use springs to apply tension to the chain, just like the old style of tensioner did. The oil is used only for damnping, acting just like a shock absorber. The damnping effect extended the life of the springs, preventing fatigue failure of the spring.

John Gulliver

Bruce, I have ordered some late idler arms ('82 + I think) which have a wider bearing surface than my '73 originals. My original idlers have an alloy spacer. One story is the narrow bearing surface on the old idler arms caused binding, which lead to probs. I am also going to look at the chain, apparently it can get mis aligned and run simplex, at the same time gnawing away at the crank-case - which could cause quite a noise! Good luck with it, I'll keep you posted...John

bds1

Yes keep me posted John, last nite I used my frame jack to apply oil pressure to the tensioner. At about 14 psi it starts to leak oil via the bypass. I tried both sides and both open at the saem 14 PSI. SO I assume that my tensioners are both good or (both bad I doubt it).

I really don't like the bleeding of precious oil pressure away from my CAMS via the "T" to the tensioners. Hope the spacers do the trick or its back to non-oil fed tensioners!

Bruce

MRFLATSIX

I rebuilt my 1970 911E in 1998 after taking Bruce Anderson and Jerry Woods' overhaul class (a great experience by the way}. I installed the pressure fed tentioners and found them to be very noisy.In fact they were so noisy I took the car to the best Porsche shop in the area and they said "there doesn't seem to be anything wrong,it's just noisy." It was so anoying I took them out and bought brand new hydraulic tensioners and installed those with the guards and it was a lot quieter. I think the real problem with rhe old tentioners is the chain wheel support. Porsche finally chaged those parts and gave them more bearing surface. I understand that there are fewer failure with the new parts.

Richard C2S

A friend who races a former IROC 911 (w/2.7 liter engine)in vintage races seems to feel pretty comfortable with the spacers Bill told us about and w/ guards instead of the Carrera update. I've heard this from a few other people also. Is the Carrera update not really necessary or not the way to go? Between the kit and the labor, its more than a few bucks. On the other hand, rebuilding an engine will cost a whole lot more.

Richard

p.s. I'm about to have it done tomorrow or Wednesday. Based on what I've read here, I don't know what to do.

John Adams

I installed oil fed chain tensioners on my 80SC in May of 2001 along with the later style sprocket support arms. I installed the tensioners right out of the box without priming them and had no problems.