Mr Jones

My 2013 W204 C63 was in at the MB dealership for a new Voltage Regulator, and they noticed a slight oil leak. There’s definitely a small leak - I can see some oil. They investigated and it seems I need to replace the passenger side Valve cover gasket. The service advisor said they recommend replacing the valve cover at the same time because there are always issues if they replace the gasket with the old cover. Has anyone ever heard of this? Do the old covers warp or crack when removing and replacing? Or is it common practice to just remove the cover, replace the gasket and reinstall the old cover?

Cwagon

I have read that the plastic valve covers on FL versions can warp or crack when removing and replacing gaskets.
FCP now supply the gasket with new bolts and spacers so maybe the spacers were collapsing which results in warping or cracking.
Some have said the cracking is so fine sometimes its almost impossible to see without twisting the cover which in itself could cause a crack.
When I replaced my lifters a couple of years back, I had a slight leak on my right side cover which I found when I was searching for a burning oil smell.
BTW my covers didn't leak before that.
Anyway I recently rebuilt my cam adjusters (C63 Motorsport kit) with new FCP gaskets, bolts and spacers and so far all is dry.

go team

They need to be removed gingerly. Back the bolts out slightly one at a time from the middle outwards otherwise they risk warping.

I take out the back outer corners first however (most difficult of all bolts to remove) and then incrementally take out the others. I believe 13 bolts total per side minus the bracket on the drivers side.

Cammer88

Recently did both my gaskets and did not replace the covers.

markov77

I'm just about to do this for the first time. Any tips/tricks for making it go smoothly?

Cammer88

Give everything a good clean before you pull them off (vacuum any sand road grime ect). As others mentioned loosen from the middle working your way out. Carefully inspect for cracks!! My driver side leak was in fact a hairline crack and not gasket failure. When reinstalling be careful the spark plug tube gasket stays on ( driver side can be tricky with engine harness in the way). Follow proper torque specs/configuration!

roadkillrob

I had one crack an leak (2014 507 at 35k miles) it had been off a couple times. FYI they come warped, bought one and put a straight edge on it and was like 1/2 warped end to end, took it back dealer ordered another one and basically the same, shop foreman says they all come like that and they just bolt them down as per WIS and have not had an issue with them, so seems they come a bit warped or pre-stressed for a reason, i bolted it down and has been find for over a year.

swedepat

I inspected my cams and headbolts recently, just took the covers(plastic) off and put them back, no more thought behind that, went all fine, no leaks, i even reused old gaskets, they were soft and squishy still = no problems.

You guys overthink to much

rawkkrawler

A quick search brought me here, as it relates to my question. I'm about to do the 63 Motorsports lock plates as well as the PCV. Most parts from FCP see pretty straight forward, except my question regarding valve cover gaskets.

My C63 is a 2013 P31 spec. FCP states their gaskets are for plastic covers only. Did the P31 use plastic? Or do I need something different? FCP is selling the gaskets as a bundle with the lifters, that's the route I'd like to go.

Already reached out to FCP,, just waiting on a response. Figured I'd also post here as it may help someone with the same question.

Thanks!

roadkillrob

your 2013 will have the plastic covers, the big difference is the plastic cover uses the orange gaskets around the spark plug holes and the aluminum older covers used green gaskets for the spake plug holes. I have used their seals before and they had the right part numbers in the kit. I think it was mid 2011 and up that use the plastic covers, for sure 2012 and up.

skullbox15

I replaced the gaskets on both of mine my drivers side started leaking first. On the C-class the driver side is kind of a ***** because there isn't much room and the wiring harness is hard to move/work around. You'll need to be careful you don't kink that one as I did the 1st time and had to re-do it. Passengers side is easy. I wouldn't plan on replacing the covers but you might want to buy all or a few new bolts. They say "one time use" but I don't see why as they aren't torque to yield. I re-used all my old ones except 1 on the drivers side which for some reason wouldn't stay tight. The spark plug O-rings seem to be the worst. Mine were really hard compared to the cover gasket.

My advice if you are thinking of doing the PCV, do the injectors at the same time. I did the injectors first therefore had to take the fuel rail out twice. I also did the 63 motorsports adjuster plates and new lifters but I had my local indy shop do them as I didn't have the time/energy to take that project on.

rawkkrawler

Thanks for the tips.

Ive ordered the lifter kit, includes the gaskets and new bolts. Did the fuel injectors, pulley/belt kit, power steering reservoir, plus regular maintenance last month.

Ordered the lock plates and timing kit as well.

With 85k miles, I’m anxious to open everything up to see how things look.

WidowrRacing

Would it not be beneficial to swap out the plastic valve covers for the aluminum ones if replacing the gaskets?
I would think it shouldn’t be that hard to find a set.

rawkkrawler

Nothing leaks now, just wanted to have all the correct parts/gaskets ordered and on hand before opening it up. No sense spending money on a problem that doesn’t currently exist.

norb

Why did they switch to plastic. Is this an upgrade from the aluminum ones?

roadkillrob

It is an upgrade if your an accountant at Mercedes and can make it for 1/10 the price and then sell one or 2 to everyone post warranty vs the aluminum ones that is expensive to make and lasts forever!

norb

OK, I guess I'll keep mine. lol.

roadkillrob

Ya a few people have swapped the plastic to aluminum when they have cracked, plastic ones are like 300 each, so cheaper in the long run to buy 2 used aluminum ones and never have an issue again if you are keeping the car for a long time.