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Discussion Starter · #1 ·
Hi all;

My 2000 V6 is driving me nuts. I keep springing oil leaks, but they are moving around from place to place.

Background.

Last winter the car skipped timing and I had to rebuild the p/s (passenger side, not power steering) head. When I did that I used a cheap Chinese CCT. Shortly after installing it I noticed an oil leak from the CCT on the part opposite end of the solenoid. I put JB weld in there and it halted the leak for a time. Then the leak cam back from another part of the CCT. I had a used one on hand, so I decided to swap it out. I accomplished that swap, but noticed a p/s leak from the back of the engine. It was soon joined by a leak from the back side of the d/s. These were visually confirmed by locating where the smoke was coming from. Inspection with fingers and mirror showed oil drip from the cam cap covers (the round seals at the back). I could actually see a small drip of oil when the car was at rest. So I just replaced both cam cap covers. Started the car and now it is leaking from both sides of the engine judging by the smoke and smell pouring off the engine after running it for about two minutes. It was not leaking from these spots before I changed the caps but seems to be now although I cannot see or feel any leaks on either side of the VCGs. The caps are not now leaking. The car has one of the upgraded oil caps that is supposed to let out excess pressure. When I did the work on the head I inspected all the PCV lines (the brittle plastic ones) and they are all very clear and none are broken or clogged. I am wondering if, when I did the head work I did not reconnect the PCV valve correctly. Is it possible that if I did not connect that valve correctly I would build up pressure even with the modified filler cap to blow my seals? If so does anyone have a picture showing which hoses go where?

Any ideas as to why I have these migrating leaks besides the PCV system. The valve itself might be clogged, but it is only 4 years old and I have only used full synth since it was replaced maybe four years ago.

Also any suggestions as to the best valve cover gaskets to use?

Thanks
 

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There has to be some part of the PCV system that is giving you the pressure. I would check every part of the system if not replace it. Are you getting suction from the oil cap or dip stick? I have used Fel-Pro gaskets with good results.
TomK
 

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If the PCV valve is on backwards it will certainly act like a clogged system and not allow the engine to breath. Creating too much internal pressure and leaks at the most common places that leak when you have a clogged PCV system.

I suggest you replace the entire system along with the small vacuum hoses. Making sure you have all the valves going the correct way before replacing any caps, gaskets and what not.
 

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Discussion Starter · #8 ·
Hello again.

I performed the suction test. Ran the car and pulled up the dipstick to different heights and no suction on it at all. I pulled it only like 1mm out of the hole and it stayed put. I also tested the oil filler cover and it came off easily. I put my hand over the filler hole and felt no suction at all. Doesn't this mean that the PCV system is fine? When I rebuilt the P/S head last year I did carefully inspect the PCV system (except for the suction pump blow through) and all those hoses were in very good condition.

Also, as I ran the car (it has probably run for less than 30 minutes total in two separate starts) I was able to localize the oil smoke to the exhaust components on the back of the engine. What I mean by that is that oil is burning off both the exhaust ports. My follow up question is whether it is possible that oil dripped out while replacing the cam caps and that the smoke is just old oil burning off. How long would the car have to run before the old oil was burnt off? Obviously that would probably depend on how much oil was on there to start with, but a ball park guess for an engine that had only a small drip from the cam caps for less than 1000 miles and whatever would have dripped out during the cap change.
 

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If the caps leaked, then the oil leaked on top of the exhaust manifold flange and trickled further on the downside of the converters. you can get under the car and wipe the oil w/ a soapy solution (or Purple Power, Power Green, etc) followed by a dry wipe, if you are concerned with the time needed to burn that dripped oil.
Unless you take the heat shields off (u need small hands), you won't be able to clean the exhaust manifolds (case of valve cover/s gasket leak). On the driver side though it entails also removing the bracket holding the return coolant pipe, not a simple proposition either.
 

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Discussion Starter · #10 ·
So I ran the engine for 1/2 hour straight at idle and at first the burning oil smell appeared, then it seemed to die down and go away. I took the car out for less than a minute and the smoke was clearly coming out again. I let the car cool down and felt all along the VCG on both sides and nothing wet at all. Checked the cam caps and nothing wet. Yet I can see on the exhaust manifolds oil wet and the smoking definitely became more pronounced after it had been driven for a (1) minute.

What I'm trying to determine now is if I am dealing with a leak or residual oil. Everything VCG and cam caps related seems dry. I jacked up the car and looked underneath to see if I could see anything there. On the pass side I could see a (1) drop of oil hanging from the Kombi Valve and from the adjacent coolant pipe on the right side(p/s). I could see no drop of oil on the left side (d/s)but there did seem to be some oily gunge just above the manifold. I want to emphasize that everything above the manifold on the back of the head is dry. I am attaching pictures if anyone has any idea as to what these leaks may be coming from, because they really don't seem to be coming from VCGs or caps.
 

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Notice in the '4 corners' underneath the valve cover gasket, Hi-Temp silicone is required in these areas otherwise oil will leak.

 

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Discussion Starter · #14 ·
Thanks for the help AP. I've actually done the VCGs twice in the last year trying to run these leaks down so I know about putting the silicone where you pointed out and it is there and not leaking. Also I did put sealant under the end cap journal and used old style cam seals. In any case I can't feel or see any oil around those areas. I did use sealant under the cam cap and I have put eyeballs on those as well. I edited the picture to show places that for sure oil is NOT leaking.
I don't think that anything is leaking from under the P/S CCT but it is very hard to get a mirror or hand in there.
 

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Check that you are not leaking power steering fluid from the hose that runs over the top of the valve cover and down the back of the motor. The connection at the back might be leaking and causing the fluid to drip down the back of the head.
 

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Discussion Starter · #16 ·
Thanks for the suggestion Paul.

I looked where you suggested and no leak. I went under there and used some cleaner to clean off all the residual oil. Idles the car in the driveway for 10 minutes and no appreciable smoke.

I live on a cul de sac, so I took it out and kept it in 1st and went round the circle about five times (so literally maybe 60 seconds of driving), backed it up the driveway and there's oil smoke coming from both sides.

So I clearly have a leak coming from somewhere back there, but the leak does not seem to start until the engine is put under load. Smoke coming off BOTH exhaust manifolds and no clearly visible leaks in the areas pointed out in post 14. Does this fact point to a likely suspect?
 

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If oil is still dripping onto the exhaust manifold it HAS to be coming from somewhere which I pointed out or along the bottom edge of the valve cover.
When oil starts getting warm up to when its hot, it gets very thin. It is very hard to see when it seeps through a gasket.

I would run the car until it starts to smoke with oil getting on the exhaust manifold, with a clean white glove, start running your fingers along any area that has a mating surface.
After checking each area, look at the glove. Somewhere, you'll find where it's coming from. Careful putting your hands in there though, stuff gets stupid hot.

And should the ultra rare chance you have a hairline fracture in the BOTH valve covers, not likely but I suppose it is a possibility. :crazy:

I have seen this once. A car I worked on had a hairline fracture on one of the valve covers, It wouldn't leak until the engine got hot, and the oil was actually seeping through the aluminum cover. Once the engine started to cool down, the oil would stop leaking.

Stupid question. Are you using new valve cover gaskets? If you re-use the gasket, all bets are off on its ability to seal up properly.
 

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Another rare possibility.
Are you sure the CCT's are torqued down properly. Those things need to be tight! However, if you've got an engine where the CCT's have been replaced a number of times, there is possibility that the threaded hole has it's threads pulled out.
Aluminum threaded holes can only be used so many times before the threaded portion of the hole begins to loose its holding power.
The screws on the CCT should be torqued to the proper amount, when approaching that torque setting, the screw should have a fair amount of resistance to turn. If it feels like it wants to keep turning with no increase of resistance, that spells doom.

You say you swapped out the CCT gasket with a used one. That is a no-no, which I made reference to in post# 11 in the notes upper right corner. You must use a new CCT gasket every time the CCT is loosened up.
 

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Discussion Starter · #19 ·
Thanks AP.

This is truly driving me crazy.

This has been seemingly leaking for a little while. So to go back a few steps. I had what seemed to be a leak on both sides at the back of the engine. This was after replacing a Cam Chain Tensioner that was failed. I replaced the CCT and used a new CCT gasket. Any time I have changed any gaskets I replaced with new. In other words, if I took off the VC for any work, replaced any involved gaskets with new. I used high temp sealant in all correct places. In corners of VCG, valley of VCG and in the correct places of CCT gasket. If I said I swapped a CCT gasket with a used one that was incorrect. I meant that I swapped a failed Cam Chain Tensioner Unit with a Used one. So everything was done by the book including torquing each and every nut and bolt to the correct spec (looked up in Bently) with an Inch Lb torque wrench.

So two days ago after searching and searching for this leak, I thought that maybe I have a collection of oil left over from when the old cam caps were leaking which I had replaced with new caps and used high temp sealant. So I went under the car and looked up and found a bit of wet in two places which I posted pictures of. I then cleaned all that off with rags and parts cleaner so that it was all good. I then ran the engine at idle speed until it came up to temp. I was able to maybe smell a faint bit of oil but saw no smoke at all. Then took it out and drove it in first gear around my circle 5-6 times, backed into the driveway, popped hood and I've got oil smell and smoke from both sides of exhaust manifold. I made my post yesterday (#16).

So today I took out the air filter box unstrapped all the fuel lines and pulled all that stuff out of the way so that I could get an inspection mirror back there. I also moved the coolant reservoir out of the way on the other side so I could get back there.

I have now fully inspected the back of the head on both sides. I have laid eyes on all mating surfaces, the 1/2 moon plug, the cam caps the corners ...everything and there is absolutely NO sign of a leak from anywhere. I am 100% certain. No thin film. No regular nothing. Clean as a whistle.

I do notice that the exhaust manifold flange seems to be sort of uniformly wet on the downside of the of exhaust manifold flange on both sides. Could unburned oil be somehow making its way into the exhaust manifold, condensing at the flange and then burning up? If so, what would cause that? Is there any way to test this theory? The oil on the dipstick appears normal, not milkshakey in any way.
 

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Thanks AP.

This is truly driving me crazy.

This has been seemingly leaking for a little while. So to go back a few steps. I had what seemed to be a leak on both sides at the back of the engine. This was after replacing a Cam Chain Tensioner that was failed. I replaced the CCT and used a new CCT gasket. Any time I have changed any gaskets I replaced with new. In other words, if I took off the VC for any work, replaced any involved gaskets with new. I used high temp sealant in all correct places. In corners of VCG, valley of VCG and in the correct places of CCT gasket. If I said I swapped a CCT gasket with a used one that was incorrect. I meant that I swapped a failed Cam Chain Tensioner Unit with a Used one. So everything was done by the book including torquing each and every nut and bolt to the correct spec (looked up in Bently) with an Inch Lb torque wrench.

So two days ago after searching and searching for this leak, I thought that maybe I have a collection of oil left over from when the old cam caps were leaking which I had replaced with new caps and used high temp sealant. So I went under the car and looked up and found a bit of wet in two places which I posted pictures of. I then cleaned all that off with rags and parts cleaner so that it was all good. I then ran the engine at idle speed until it came up to temp. I was able to maybe smell a faint bit of oil but saw no smoke at all. Then took it out and drove it in first gear around my circle 5-6 times, backed into the driveway, popped hood and I've got oil smell and smoke from both sides of exhaust manifold. I made my post yesterday (#16).
Ok. It's good to know you acknowledge and seemingly have done everything by the book.


I do notice that the exhaust manifold flange seems to be sort of uniformly wet on the downside of the of exhaust manifold flange on both sides. Could unburned oil be somehow making its way into the exhaust manifold, condensing at the flange and then burning up? If so, what would cause that? Is there any way to test this theory? The oil on the dipstick appears normal, not milkshakey in any way.
This is the part I'm having difficulty with. Oil will burn completely off the exhaust manifold in approx 20 minutes.
If it is still looking 'wet' and still smoking, then there is oil coming from somewhere. And that somewhere right now is still elusive.
Or, there could be the remote possibility your engine is pumping oil past the piston rings, entering the exhaust manifold and leaking through the downpipe to manifold connection.
The quickest easiest way to check for this condition is, pull the spark plugs and check the electrode. It should absolutely dry. If it's wet then something is wrong.
 
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