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Discussion Starter · #1 ·
I recently changed my valve cover and CCT gasket using Victor Reinz brand. After I put it back together it does not appear to be leaking as I have checked the seam and it looks dry. I've noticed that at the very bottom of the heatshield that attaches to the engine, closest to the front of the car, there's an oily residue. I had cleaned the heatshield with electrical cleaner before I installed it. I thought it must be a fluke maybe from my gloves or something so I sprayed it down again, but it has reappeared. Is there anywhere that oil can get deposited to that area other than the valve cover?

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Discussion Starter · #3 ·
Did you put RTV sealant in the tight corner bends of the VCG?
If you mean on the right angles no. I did something other than RTV on the recommended points, like at each side of the CCT. I used Hylomar AF (advanced formula) which is a non curing gasket dressing. I applied only to the surface the valve cover gasket sits on, and not the gasket or valve cover itself. I don't see any leaks from the recommended points, or anywhere else on the seam.
 

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I want to know why as well. The gaskets almost never leak from the RTV points, if applied correctly. If it ain't broke, don't fix it. It is meant to be an impervious seal that cannot be broken unless you scrape it off.
 

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No RTV on any of mine either except at the specified points per the Bentley.
No leaks what-so-ever.
 

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Discussion Starter · #7 ·
I had a printed out DIY that had a vw graphic showing where to apply the gasket compound. If I recall correctly it did not list the corners as an area to put the gasket compound. It only had a few arrows to some curved areas to put some dots of compound so that's what I did, just put the compound on those areas and no others. I will check the Bentley manual this evening and compare.
 

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I had a printed out DIY that had a vw graphic showing where to apply the gasket compound. If I recall correctly it did not list the corners as an area to put the gasket compound. It only had a few arrows to some curved areas to put some dots of compound so that's what I did, just put the compound on those areas and no others. I will check the Bentley manual this evening and compare.
To clarify, that is what is usually meant when we say corners on these. Not technically a corner, but where two pieces meet on the head. You indicated the correct points. We are questioning why not RTV which is "permanent" or one time use and specifically called for by VW.
 

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Aye. "non-curing" implies it never sets up and stays at least partially fluid forever. Since the valve cover almost always has pressure (positive or negative!) on it, I would expect such a dressing would not last long.
 

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As a point of reference I will go out on a limb here and say , the vast majority of VC leaks on the 1.8s are from a failed or component failure on the PCV system. If when a check valve fails/marginally failing, the turbo boost pressure not only goes to the intake manifold but to the engine internally, valve cover included. The valve cover is possibly exposed to lets say 10 psi max. Over the area (lets say 100 square inches) of the valve cover that is a great deal of pressure to be exposed to, lets say from losses from the rest of the engine that it (VC) is only exposed to 2 psi. that is enough to distort the VC to allow oil to squeeze out past the gasket. How is your PCV system as to components and maintenance ?
 

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Discussion Starter · #12 ·
I replaced a bunch of PCV components years ago when I had a cracked oil breather tube and I cleared out a clog from the hard metal pipe that runs to the left of the engine. When I took that metal pipe off to get at the valve cover this time it had an oily sheen to it but no clogs or anything. Same for that puck thing, oily but not clogged. Do you have a thread recommendation for how I can test the PCV system?
 

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Discussion Starter · #13 ·
I haven't tested the PCV system yet but I went ahead and replaced the suction pump proactively since I know that can be the cause of pressure build up. I replaced it with an assembled breather hose (it goes by 058133784AF on Amazon which is the part number for the breather hose but is also used to refer to an assembly that includes the hose and suction pump and check valve).

Also, I bought some UV tracer which I'm going to put in the oil to help trace where the leak originates.
 

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Discussion Starter · #14 ·
A few months ago the Reinz valve cover gasket started leaking from its half moon onto the cat and the car smelled like burning rubber. Yesterday I replaced it with a fel pro and this time I used ultra copper RTV sealant, just because that's what I had on hand. I really didn't want to use curing sealant because I suspect it will be much harder to get it off next time but OTOH I really don't want a leak again. Also, one thing I didn't expect is RTV curing time is 24 hours (at I assume 70F?). Since it's freezing here I'm waiting at least two days before starting the car.

As cchief22 mentioned, the PCV can be the problem so I also replaced the puck valve and the T valve(? -the one that sits below the intake and is supposed to have a rattle when you shake it). The old PCV T that I removed didn't rattle so maybe that's something.
 

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A few months ago the Reinz valve cover gasket started leaking from its half moon onto the cat and the car smelled like burning rubber. Yesterday I replaced it with a fel pro and this time I used ultra copper RTV sealant, just because that's what I had on hand. I really didn't want to use curing sealant because I suspect it will be much harder to get it off next time but OTOH I really don't want a leak again. Also, one thing I didn't expect is RTV curing time is 24 hours (at I assume 70F?). Since it's freezing here I'm waiting at least two days before starting the car.

As cchief22 mentioned, the PCV can be the problem so I also replaced the puck valve and the T valve(? -the one that sits below the intake and is supposed to have a rattle when you shake it). The old PCV T that I removed didn't rattle so maybe that's something.
Can't say that I have ever heard a VW pcv (bleeder) valve rattle. The older JP and US car PCV valves, yes, but not ours. Or maybe I never thought to try.
 

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Discussion Starter · #16 ·
Can't say that I have ever heard a VW pcv (bleeder) valve rattle. The older JP and US car PCV valves, yes, but not ours. Or maybe I never thought to try.
I don't remember where I read that it's supposed to rattle if you shake it. The replacement I used is a Vaico Germany part and it had an audible rattle when I shook it.
 

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the check valve located below intake will "rattle" so to speak as it has a "ball" or similar part that moves and seals, unlike the little disc ones like on the other vacuum lines which are a flap/diaphagm style. The one under the intake is subjected to crank gases and crap and overtime it condenses on it rendering it uselss.
 

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The PCV valves I have seen on the 1.8T Passats are spring-loaded discs, not ball valve.
 
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