macadamianut

Hi all,

Still in need of transaxle repair, and now this!

I am hearing a clatter from the top of the engine, seems to be the loudest over the center, underneath the variocam badge. Idle seems rougher than normal, but then I've not had a very smooth idle since purchase 2 1/2 years and 10000 miles ago. Mileage is now 78,000. Belt service and front engine reseal done at time of purchase. Car has no engine mods other than the "airbox-holey-mod with K&N."

Any thoughts?

Thanks,

LTCMontana

variocam chain pad wear. Plenty of discussion here. Do a search.

PorscheDude1

Pull the cam cover and check.

Joel8005

My coupe is going to have the cam box off this weekend for a inspection.....lets see if anybody paid any attention to the girl before she came my way.

Good luck!

odurandina

could be oil starvation up there due to bad rod bearings.... but that's more of a longshot.

RajDatta

As suggested, it sounds like worn variocam pads. I would strongly advise against starting the car until the valve cover has been removed and the variocam inspected.
Its not common for a 968 with this kind of mileage to have oil starvation issues from rod bearings. You might get similar symptoms from a a cracked oil pan pickup tube.
If variocam tenioner and pads look fine, I would look at oil pickup tube. You could be sucking in air into the system, which makes variocam very loud.
Did you have a misaligned lower balance shaft at any point?
Raj

John Etnier

Is it still true that Zims is the best source for cam tensioner pads, in that they sell the pads separately?

968rz

I just picked up a set from Pelican Parts.

Stephenwz968

I got all the parts needed for that from Sunset Porsche. Check out the DIY by Raj and Arash.

RajDatta

I have found the pads to be cheapest at Sunset. They are approx $16 a piece. You have to specify two bottom ones, because according to PET, Porsche does not sell the upper pad. They are both the same and you can use a bottom pad for top as well.
Raj

macadamianut

Wow, just read the DIY which seems daunting, but great post.


I'll pull the valve cover and give a look. What am I looking for? Grooves cut into the surface, cracking? When inspecting the cam tensioner itself, what am I looking for? In the chance that the pick-up tube is cracked, would I be able to view from the top? Should I pull off the top of the pick-up tube and check the check-ball too?


Raj, I have almost no history on this car other than what I've done. Belt service and re-seal is the only major thing that's been done engine-wise. I don't know if the balance shaft was ever misaligned. Idle has always been rough and gearshift always vibrates.

My oil pressure gauge skips around a bit at warm idle. between the 2-3 range. What does this mean??? High rpm is always somewhere steady between 4 and 5.

Thanks.

Stephenwz968

I'd clean the ISV to help the rough idle, and maybe run a few bottles of Techron through, or have your injectors serviced.

As far as pulling the cam cover, you're looking to see if tha pads are cracked and grooved, and make sure the chain is in tact, and that there are no missing teeth on the cams! If you can take a few pics and post them here it would help.


The oil pick up tube is in the bottom of the motor, in the oil pan, so you'd have to drop the crossmember and oil pan to take a look.

RajDatta

So far, all your symptoms seem to be pointing to a cracked pickup tube. When was the last time you had your balance shafts checked? Are they currently aligned?
I would still start with removing the valve cover, since its an easy job. I have posted pictures of pitted variocam guides in the past. You should be able to find some. You want to make sure that chunks of guides are not missing. This could be a good time to reseal the valve cover as well.
Raj

macadamianut

Photos,

Looks pitted. But I don't see any cracks, chain is very tight and looks okay.

RajDatta

Pad looks fine. Grooves don't look too deep either. I would also check the variocam solenoid for normal operation. You should be able to activate it and deactivate it by giving voltage. This would be a good test while the valve cover is off.
Have you ever confirmed if the bs belt is aligned and bs pulleys are aligned? Does the car have vibrations while accelerating?
Raj