Valve cover gaskets
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From: Shamong, NJ
1998 C43, 2001 SLK320
Valve cover gaskets
My 1998 C43 valve cover gaskets have been replaced for leakage at 142k, 152k and now 161k. They have become an expensive 10k maintenance item. My long term mechanic says the covers are aluminum and likely have some warpage. Is this likely the case, would replacing them likely solve the problem, and is replacing them the only viable approach? They are quite expensive.
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From: Bolingbrook Illinois
1999 C43 Amg
My 1998 C43 valve cover gaskets have been replaced for leakage at 142k, 152k and now 161k. They have become an expensive 10k maintenance item. My long term mechanic says the covers are aluminum and likely have some warpage. Is this likely the case, would replacing them likely solve the problem, and is replacing them the only viable approach? They are quite expensive.
Just use permatex right stuff and will last much much longer. Have your mechanic put a small amount on top and bottom of the rubber gasket and that's it.
I use this stuff to seal the half part of intake manifold and I've never have any vacuum leaks. This sealant is VERY good. Just make sure to let it dry as many hours as possible before driving. I once did a car with this and had to drive out after half an hour and no leaks to this day and it's been close to 2 1/2 years. But if I could let it dry for hours I would.
Don't let your machanic convince you that you shouldn't use a sealer. IF your valve covers are really warped this will fix that. It's that good!
https://www.amazon.com/Permatex-25224-Right-Stuff-Gasket/dp/B000HBM4FQ
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From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
My 1998 C43 valve cover gaskets have been replaced for leakage at 142k, 152k and now 161k. They have become an expensive 10k maintenance item. My long term mechanic says the covers are aluminum and likely have some warpage. Is this likely the case, would replacing them likely solve the problem, and is replacing them the only viable approach? They are quite expensive.
As Speed43 says a good quality sealant is a must and if done correctly should last as long as the engine does
Did mine on both sides top and bottom in 2012. No problems since.
Last edited by DRBC43AMG; Aug 31, 2017 at 05:19 AM.
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From: City with Tall buildings!
C43/55,2k11 Volvo S60 T6AWD,2k Audi B5 S4,95 Eagle Talon Tsi AWD 500+awhp
This is how I fixed my oil leak. The valve covers and breather cover surfaces need to be cleaned properly.
https://mercedessource.com/store/m11...s-demand-video
https://mercedessource.com/store/m11...s-demand-video
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From: Vancouver, B.C., CANADA
2006 E55 AMG/1996 C36 AMG/1999 C43/55 AMG/2021 Toyota Tundra Crew Max TRD Sport Premium
My 1998 C43 valve cover gaskets have been replaced for leakage at 142k, 152k and now 161k. They have become an expensive 10k maintenance item. My long term mechanic says the covers are aluminum and likely have some warpage. Is this likely the case, would replacing them likely solve the problem, and is replacing them the only viable approach? They are quite expensive.
Last edited by nkctb7; Sep 7, 2017 at 01:50 PM.
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From: New Jersey
1999 AMG C43
he said it was an "expensive" 10k repair item. sounds like he just learned about the "mercedes tax" every dealership and some mechanics believe they have the god-given right to charge.
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From: City with Tall buildings!
C43/55,2k11 Volvo S60 T6AWD,2k Audi B5 S4,95 Eagle Talon Tsi AWD 500+awhp
Never have heard the covers warping on M113 engines but could be wrong. Have you an indication where the leak(s) are coming from? Breather top covers or at the bottom of the valve cover?
As Speed43 says a good quality sealant is a must and if done correctly should last as long as the engine does
Did mine on both sides top and bottom in 2012. No problems since.
As Speed43 says a good quality sealant is a must and if done correctly should last as long as the engine does
Did mine on both sides top and bottom in 2012. No problems since.
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From: Miami, FL
2003 CL 600
More and more of these are showing up with porosity in the covers, requiring replacement. If they are leaking every time, that may be what's happening. You do need to ensure the covers are being cleaned and sealed properly.
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what are the tightening bolt procedure for valve cover gaskets?
do we have anyone with WIS who can show in what order to tighten first bolt then go to bolt no.2 then bolt no.3 etc. etc.?
there's a thread on C63 forum, these valve covers have 13 bolts or so?
someone posted the tightening steps for valve cover bolts.
I can't find them for C43.
need a WIS sketch for C43.
do we have anyone with WIS who can show in what order to tighten first bolt then go to bolt no.2 then bolt no.3 etc. etc.?
there's a thread on C63 forum, these valve covers have 13 bolts or so?
someone posted the tightening steps for valve cover bolts.
I can't find them for C43.
need a WIS sketch for C43.
Last edited by KJI3jflarryfe93; Jun 15, 2018 at 02:02 PM.
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From: Bolingbrook Illinois
1999 C43 Amg
See thread below, the guy mentions top middle to down middle than going out to the sides.,...
http://www.benzworld.org/forums/show....php?t=2273162
http://www.benzworld.org/forums/show....php?t=2273162
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See thread below, the guy mentions top middle to down middle than going out to the sides.,...
http://www.benzworld.org/forums/show....php?t=2273162
http://www.benzworld.org/forums/show....php?t=2273162
according to Benzworldlink,
seems like there are different lengths for valve cover bolts, it's easy to screw the wrong bolt length to wrong place
Last edited by KJI3jflarryfe93; Jun 15, 2018 at 01:56 PM.
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From: Bolingbrook Illinois
1999 C43 Amg
If it worries you get a cardboard box and make an outline of the valve cover pattern. Punch some holes where the bolts should go. Than as you pull one boltbout stick it in the proper hole. Can't mess up like that. I've done three c43s valve cover gaskets and have never needed to do this. Not a hard job at all. Use a little silicone on both sides of the rubber gasket for 100 percent seal. Otherwise, you have to be precise bolting the bolts down.
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there should be a stickie for this gasket swap valve cover job.
torque is 9NM according to MB.
yeah, that's a good idea cutting out a V-cover stencil from cardboard paper then punching each bolt in the right place.
the only issue is to tighten correct bolt first, then go with the other ones in correct order
see bolt tightening for C63 the first reply
.https://mbworld.org/forums/c63-amg-w...l-leaking.html
we need a WIS stickie for C43
torque is 9NM according to MB.
yeah, that's a good idea cutting out a V-cover stencil from cardboard paper then punching each bolt in the right place.
the only issue is to tighten correct bolt first, then go with the other ones in correct order
see bolt tightening for C63 the first reply
.https://mbworld.org/forums/c63-amg-w...l-leaking.html
we need a WIS stickie for C43
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From: Miami, FL
2003 CL 600
There isn't a listed pattern for those engines, here is the WIS doc for the valve cover replacement. The only special note is to check the gasket around the semi-circles at the end of the cover for proper seating.
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ProjectC55 mentioned in his previous reply when everything is cleaned properly, new gasket is fitted then put V-C back to it's place.
The first round when tightening each and every bolt, is to tighten each bolt with 4NM.
The 2nd round to tighten each and every bolt with 8NM.
WIS says 9NM.
I only want to re-tighten my bolts not doing any replace for V-C gasket.
These engines with age or mileage builds up will eventually weep their own pants.
How much torque do these bolts handle before they snap?
If you have bad luck to snap one bolt , then a helicoil is necessary.
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From: Land of mountains, cheese, chocolate and watches
12' W204 C63 AMG coupe "T-Rex", 12' W451 Smart Fortwo Pulse (99' W202 C43 AMG + Ultima Can-Am sold)
thanks for the info.
ProjectC55 mentioned in his previous reply when everything is cleaned properly, new gasket is fitted then put V-C back to it's place.
The first round when tightening each and every bolt, is to tighten each bolt with 4NM.
The 2nd round to tighten each and every bolt with 8NM.
WIS says 9NM.
I only want to re-tighten my bolts not doing any replace for V-C gasket.
These engines with age or mileage builds up will eventually weep their own pants.
How much torque do these bolts handle before they snap?
If you have bad luck to snap one bolt , then a helicoil is necessary.
ProjectC55 mentioned in his previous reply when everything is cleaned properly, new gasket is fitted then put V-C back to it's place.
The first round when tightening each and every bolt, is to tighten each bolt with 4NM.
The 2nd round to tighten each and every bolt with 8NM.
WIS says 9NM.
I only want to re-tighten my bolts not doing any replace for V-C gasket.
These engines with age or mileage builds up will eventually weep their own pants.
How much torque do these bolts handle before they snap?
If you have bad luck to snap one bolt , then a helicoil is necessary.
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on one place, have a tiny stain of olio coming out down on sparky plug.
I want to tighten this bolt, therefore wudd be good to know the bolting order from first to last for futura references if I discover more leaks.
there shudd be a sticky DIY for this VC job, everyone will experience this problem sooner or later.
If we have a sticky thread then we all know the procedure of cleaning, replacing and refitting everything back 2gether.
there are no sticky DYI threads for our C43.
I want to tighten this bolt, therefore wudd be good to know the bolting order from first to last for futura references if I discover more leaks.
there shudd be a sticky DIY for this VC job, everyone will experience this problem sooner or later.
If we have a sticky thread then we all know the procedure of cleaning, replacing and refitting everything back 2gether.
there are no sticky DYI threads for our C43.
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From: Miami, FL
2003 CL 600
Same torque. The gasket will compress over time, and it will take more turns of the screw to reach that same torque. 9Nm is nothing, barely hand tight with a screwdriver. I have done so much mechanical work I know about what you need for the fasteners in question by feel, but it should be moderately tight. Go around them all several times, on a large item like a valve cover, with small screws, as you tighten more of them, the first ones will loosen. If you just went around one time, the first ones you did will probably not be tight enough. keep bringing them all back to the same tightness, until they don't loosen up as you come back to them.
Last edited by ItalianJoe1; Jun 16, 2018 at 02:37 PM.
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Same torque. The gasket will compress over time, and it will take more turns of the screw to reach that same torque. 9Nm is nothing, barely hand tight with a screwdriver. I have done so much mechanical work I know about what you need for the fasteners in question by feel, but it should be moderately tight. Go around them all several times, on a large item like a valve cover, with small screws, as you tighten more of them, the first ones will loosen. If you just went around one time, the first ones you did will probably not be tight enough. keep bringing them all back to the same tightness, until they don't loosen up as you come back to them.
ain't it better using Loctite in bolt threads, screws won't loosen up again?
how many spanner turns do these bolts handle with a torque wrench?
bolts will eventually snap messing with them too much?
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From: Miami, FL
2003 CL 600
how is it possible screws go loose after the first time screwing bolts back to VC?
ain't it better using Loctite in bolt threads, screws won't loosen up again?
how many spanner turns do these bolts handle with a torque wrench?
bolts will eventually snap messing with them too much?
ain't it better using Loctite in bolt threads, screws won't loosen up again?
how many spanner turns do these bolts handle with a torque wrench?
bolts will eventually snap messing with them too much?
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From: Henrico, Virginia
2014 ML350 4Matic
The valve covers have a "spacer" cast into them at each bolt location. That ensures that the correct gasket crush takes place. Once the bolts are torqued correctly the "spacers" will be in contact with the head. No amount of overtightening will add crush to the gasket. If they leak they need to be replaced. See the photo.
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From: Henrico, Virginia
2014 ML350 4Matic
That weeping is inevitable with age. As long as the bolts are still keeping the "spacers" snug against the head the only solution is to renew the gaskets. Alternatively, just clean the area periodically with a bit of electrical cleaning solvent.
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LS400
So with about 50+ years of mechanic experience, rubber or what ever it is made of is the worst material there is for a gasket even cork is better. At least Mercedes attempted to do it correct with the pads to allow tightening crush on the gasket, unlike Lexus did. I have put some of the very worse known leaker engines together and never had a leak.
