Why do the cam tower oil lines leak?

[brittbolen]

I've been trying to stop my right cam tower oil line from leaking (simple lines, from the pre-hydraulic tensioner days) and I can't understand why it's leaking. The fittings in the line don't appear to be leaking, the oil seems to be coming from the fitting on cam tower, but there doesn't appear to be anything wrong... i've tightened the heck out of it, and that has definitly helped, but I still leaked a cup of oil in just a few hours today...

I suspect I should just replace the whole setup. That would be the line, the hollow bolt, 2 crush rings, and whatever hardware attaches at the other end, right?

Should (can I?) replace the fitting that screws into the engine block too (didn't see a part in the pelican catalog)? I guess I should remove the valve cover to make sure that fitting is installed nice and tight.

thanks for the help!

Britt

[HarryD]

Most likely you have overtightened the crush rings. When you do that, they deform and leak. They fall do not fall int he category "if a little is good, a lot must be better".

Get some new ones and tighten them to spec and no more.

[brittbolen]

How much should the fitting be tightened?

Britt

[Randy Webb]

On my tensioner type lines, the vibration actually de-weled the joint. It fractured and spewed oily smoke right in front of the organic foods market, and all the way down the street as I passed all the enviro. group offices....

It took me a long time to figure out what caused it. The intaller had not put on the extra strap that reduces the vibration. So keep this in mind if the above doesn't solve your problem.

[HarryD]

Originally posted by brittbolen
How much should the fitting be tightened?

Britt

I am not sure, others may know the correct value.

I would tighten it until the parts just touch and then a "smidge more", check for leaks and hope for the best.

[Sonic dB]

vibrations...thats why the upgrade has brackets

[brittbolen]

What upgrade and brackets? Or are you talking about the carrera tensioner upgrade?

Britt

[aigel]

The seams on the lines can develop microcracks from vibrations. No tightening in the world will fit that. Go for a complete replacement of the lines and all rings. It's only a few tens of dollars to do that.

The cam oil restrictor is a good upgrade if you put the 993 part. Might as well put that while you are at it. You should be able to find it in the PP catalog as such. The part numer is A-105-361-01.

Torque on these shouldn't exceed 10-15Nm in my book. Of course, all these connections require open end or better flare nut wrenches which won't give you the opportunity to read a torque. Just fasten it firm, until you feel that the crush washer is deformed and stop there. Do not overtighten!

George

[brittbolen]

Why is the oil restricter a good upgrade? Does the higher pressure help get more oil farther into the cam assembly?

Britt

[aigel]

Britt:

The restrictors go at the end of the cam oil lines and keep more oil *away* from the cam spray bars. That way the bottom end sees higher oil pressure and there is less tendency of foaming in the crank case from excessive oil sprayed over the cams.

I put these in my car and it increased my oil pressure about 1 bar - average. I like to see that, especially when the car is running rather hot.

Cheers, George

[Wil Ferch]

Caveat...there is an open debate on the value of the restrictors. Certainly helps bottom-end pressures and perhaps also brings more oil to the "squirters" that cool the underside of the pistons...but now you'll also have less oil to the cams, and less oil to cool the head area....

--Wil

[aigel]

Wil:

I forgot to mention, but that restrictor is a Porsche part, Porsche endorsed. I'd be more critical myself if it were something an aftermarket company came up with. I figure at high rpm, when you need it, there is plenty of oil in the top.

George