Valve Cover Nut Leak - 81 300SD - Page 2 - PeachParts Mercedes-Benz Forum

vstech · #16 10-10-2013, 09:52 PM

um... there is supposed to be a stud there, not a bolt...
it's possible that whoever put the bolt in, damaged the head...
take the valve cover OFF, and clean around the area, and take a picture of what's there, also, clean the inside of the valve cover where the bolt is touching, and photograph it as well.

whunter · #17 10-10-2013, 09:53 PM

It appears either the gasket is damaged or the valve cover is cracked.

Note: The correct stud has been replaced by a bolt.

.

whunter · #18 10-10-2013, 09:56 PM

Quote:

Originally Posted by vstech

um... there is supposed to be a stud there, not a bolt...
it's possible that whoever put the bolt in, damaged the head...
take the valve cover OFF, and clean around the area, and take a picture of what's there, also, clean the inside of the valve cover where the bolt is touching, and photograph it as well.

I agree head damage in the thread area is possible, but the cover must also be cleaned - inspected for cracks.

.

whunter · #19 10-10-2013, 10:03 PM

The correct STUD is designed for the nut to bottom out (stop) at the optimum gasket sealing pressure - stress.

A bolt can and typically will over stress the valve cover and gasket..

.

vstech · #20 10-11-2013, 11:07 AM

Quote:

Originally Posted by 300SD90

Hey all,

I noticed my valve cover is leaking oil at at least two of the nuts that hold it down. I went out and purchased new nuts and wave washers, but it still seems to be leaking. Has anyone had this problem or knows of a fix for this?

Thanks

in this post, you clearly state you have new nuts, and noplace do you mention bolts... bolts are bad. exact length studs, with nuts LIGHTLY installed, are key here...

300SD90 · #21 10-12-2013, 02:06 PM

Quote:

Originally Posted by vstech

in this post, you clearly state you have new nuts, and noplace do you mention bolts... bolts are bad. exact length studs, with nuts LIGHTLY installed, are key here...

Exactly. I'm not sure why everyone thought I was using bolts. Unless its the incorrect size, I have no idea why the oil is leaking at that point. I thought maybe someone might have had the same problem before.

vstech · #22 10-13-2013, 08:28 AM

Quote:

Originally Posted by 300SD90

Exactly. I'm not sure why everyone thought I was using bolts. Unless its the incorrect size, I have no idea why the oil is leaking at that point. I thought maybe someone might have had the same problem before.

because the picture CLEARLY shows a bolt, with a star washer under it.

are you telling me that the picture is NOT what you have on your car?

can you take a picture of YOUR car, where it's leaking?

300SD90 · #23 10-21-2013, 09:14 PM

Quote:

Originally Posted by vstech

because the picture CLEARLY shows a bolt, with a star washer under it.

are you telling me that the picture is NOT what you have on your car?

can you take a picture of YOUR car, where it's leaking?

This is my car and I promise you that there is no bolt there, it just might be hard to see because of the oil puddling around it. I'm not even sure how someone would get a bolt on there being that there are two studs that the valve cover goes onto, and then is tightened down with a washer and a NUT. I am using a nut that threads onto the stud and oil is somehow leaking through it...

vstech · #24 10-21-2013, 09:28 PM

wild.
oddities of photography I suppose.

anyway, did you pull it all off, and look over the valve cover?

300SD90 · #25 10-21-2013, 09:38 PM

Quote:

Originally Posted by vstech

wild.
oddities of photography I suppose.

anyway, did you pull it all off, and look over the valve cover?

I believe the nut was stripped so I purchased a new one. I have not tried to pull it off yet, but I know that there is some gouging from tightening the nut down without a washer. I just don't see how that would cause the oil to seep through the top of the nut. I'm stumped...

whunter · #26 10-22-2013, 08:47 AM

Quote:

Originally Posted by 300SD90

This is my car and I promise you that there is no bolt there, it just might be hard to see because of the oil puddling around it. I'm not even sure how someone would get a bolt on there being that there are two studs that the valve cover goes onto, and then is tightened down with a washer and a NUT. I am using a nut that threads onto the stud and oil is somehow leaking through it...

There are four studs mounting the valve cover.

.

Simpler=Better · #27 10-22-2013, 09:17 AM

If it was my car...
[flame suit on]
I would probably remove and clean it all and RTV down a washer. This way the nut it still easily removable and the washer seals any cracks/gouges.

My money is on a crack around the corner. It would have to be a big gouge to leak that much oil.

vstech · #28 10-22-2013, 10:01 AM

the design of the valve cover is that the GASKET seals the oil away from the stud passage. you need to take the valve cover off, and look at the passage the stud passes through and look for cracks. if no cracks are present INSIDE THE VALVE COVER, you need a new gasket.
oil should not be able to get to the nut... it should be sealed away by the gasket.

otto huber · #29 10-23-2013, 02:52 AM

If you decide that the valve cover needs to be replaced, I have one I can sell you for $30 plus shipping.

eatont9999 · #30 11-07-2013, 08:38 PM

Quote:

Originally Posted by vstech

the design of the valve cover is that the GASKET seals the oil away from the stud passage. you need to take the valve cover off, and look at the passage the stud passes through and look for cracks. if no cracks are present INSIDE THE VALVE COVER, you need a new gasket.
oil should not be able to get to the nut... it should be sealed away by the gasket.

This is why I have been so confused during this whole thread. Nut, stud or whatever oil should not be able to get to the top of the bolt unless the gasket is broken or the valve cover is cracked.

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