3.2 timing chain noise

[Zef]

I have done a search on the board, but my question found no answer...I can hear a chain rattle on the right side of the engine...but only when the engine is warm and at idle (800 RPM), like after an hour drive. No noise at higher RPM and oil press is good. The ramp or the tensioner or the chain stretch ???

[2.7RACER]

I would remove the right side timing chain cover and take a look.
Could be a worn out timing chain. Less likely would be a weak or bad tensioner.
A timing chain flopping around will beat up the ramps.
An original 20 year old timing chain deserves to be replaced.
Both sides.
Not over an hour to look at both sides. You'll need gaskets.

[Zef]

And can I do it with the engine in situ...?

[tonythetarga]

Yes you can. I just did it this past week. I think you'll also need new brass washers for the two oil lines that drop into the back of the cover. I replaced the O rings as well, but it may not be necessary, just one of those .50 cent things that is a 'while you're in there thing'. You will need to remove the muffler, heat excahge pipe that feeds the fan on the motor and the rear engine tin. I was able to loosen the engine mounts a bit to get the tin out (lowers the engine a bit). It is not difficult but will take you a few of hours.

[Zef]

Tony...I saw in Benthley manual that the replacement chain is a split one with a master link...do you used that one...and did you follow the benthley manual...I ordered the 101 project book from Wayne...I wait for it...

[Quicksilver]

Before you dive into the engine...
What kind of idle oil pressure do you have? What viscosity of oil are you using?

The Carrera chain dampers are oil pressure fed. The fact that it only does something when the oil is completely warm and oil pressure is at its lowest would lead me to believe that it may be bleeding a little fast and wants more oil.

If this is the case I would put in the later cam oiling restrictors that Porsche has superseded the earlier ones with. It is very unobtrusive and will get you at least 1.5 bar at idle.

If this doesn't seem to fit the problem then go after the damper. It isn't something that you want to wait on!

[Quicksilver]

Oh, if you do the cam oil restrictors, you will need 6 washers. one for each side of the restrictors and one under the head of each bolt to seal the banjo fitting.

[tonythetarga]

Originally posted by zefsuper911
Tony...I saw in Benthley manual that the replacement chain is a split one with a master link...do you used that one...and did you follow the benthley manual...I ordered the 101 project book from Wayne...I wait for it...

I don't know. I only did the tensioner cover gaskets, cam oil lines and oil lines that feed the tensioners. Chain was left intact.
My comments refered to removing and replacing the covers while the engine is still in the car.

[Porsche84]

I had a noise like this a few years ago on my 3.2. I replaced the tensioner on one side and the noise never returned. This would be much easier than replacing the chain, might be worth a try.

[Zef]

The viscosity of my oil is 20W50. Here in Canada in summer time the temp rarely go over more than 90 F (30 C). My oil pressure at idle is at about 1.5...no less. Is it a big job to install that cam oil restrictors...??? The rattle occur only after a 20-30 min. ride on the highway and when I park the baby at idle...if I bring the rev over 1200-1500 RPM...the noise disapear...!!!

[Zef]

Not a bad idea Jerry...is the noise coming from you chain occur only at idle...??? I suspect a tensioner (oil press or unit) because it happen only at low RPM...

[Patton]

I had the same chain rattle at low rpm. It turned out to be stretched chains. Chain Tensioner Question (pics)

[Gunter]

zefsuper911: Re: Noise. I suspect tensioner failure. Open the chain cover and check the tensioner by compressing it. Wayne's book describes the procedure. If you replace the tensioner, do both sides.
While you are in there, check the ramps.
For chain stretching, check how much room is left for the tensioner-idler-travel. Take a picture of the idler in situ so we can tell you if it's coming too close to the case due to chain-stretch.
I don't recommend to just replace the chains.
If you feed new chains onto old chain sprockets, be prepared for this:

New chains without new sprockets? Read this!

Those are the sprockets on the I-shaft, not the cam sprockets. Why take a chance?

[Zef]

Thanks a lot for advice Gunter. I will store my baby in two days for a 5 month sleeping time (You know...Canadian !"/$%? winter)
So I will open both chain housing this week end and take pictures. I will post them and will wait for your advice. Again...thank you very much....Syl

[Zef]

Update...Took the baby to go to work this morning and the oil pressure is at 3 at idle with engine warm....definitly not an oil pressure issue....I took a stetoscope equiped with a rod connected to it (I use it sometimes to isolate strange noise in aircraft engines) and can hear (very clearly) the noise coming from the chain housing and there is something chafing there. Opening will take place this weekend and pics will follow.

[Quicksilver]

Yup, time to open it up. Sounds like something was nice enough to give you a good warning.

[hcoles]

I hate to add to the "while your in there".......
as others have said...
new chains, sprockets, check arm bushings, idler sprocket shaft, might as well make and install Jerry Woods slugs...these are good insurance

maybe if the sprockets are look very good you can reuse....I didn't do that. Look on the sides of the idler and main chain gear... you can maybe see that the chain is running straight of being pushed to one side

while your in there I guess put in new ramps...some ask if the master link type chain is an issue...I haven't read anywhere that someone said there was an issue. Those little "C" clips are small and fragile be careful with them

that's my 0.02

[Zef]

OK...Both timing chain housing covers are removed.
There is the right one...the one that make more noise:


On the left one we can see that the tensioner end
has touched (but not damaged) the upper section of the housing.
And there is the left one...the more quiet one:


Now I need advice...Please timing chain guru, get up...!

[David 84 911]

Zefsuper911,

I want to follow this thread so I am replying. I have the Bently Manual and 101 projects if you don't have them and want to borrow them.

Bonne chance

[Zef]

Thanks a lot Dave...I got the Bentley as well. For now I just want to have an experienced timing chain guru to give me some advice...How to know if it's the chain that is stretched or the tensioner that is bad ??? For sure something's wrong there. If possible I want to see a pic of how look a good chain and a good tensioner....Syl