Plastics (engine bay)
Thread Starter
MBWorld Fanatic!
Joined: Dec 2006
Posts: 1,105
Likes: 11
From: Toronto, Canada
2019 C300 Wagon; '75 Triumph TR6; previous: 2004 C230 6spd sold after 17 years of driving
Plastics (engine bay)
I continue to have problems with the plastic that German cars like to use, you know the type - black matt finished plastic that is very brittle. It does not matter if it is MB, BMW or Audi/VW this material always seems to fail.
My latest breakage was my engine cover, tried to remove it to change the plugs and the front right pin would not pull out. I pulled and pulled albeit gently. It eventually came off but did so leaving a 2"x2" hole in the cover with the pin and surrounding plastic still stuck on the head. I subsequently reglued (fiberglass reinforced) that broken part back on using some West System 6-10 epoxy that I had around for my sailboat repairs. I did the repair on the underside of the cover and tinted the epoxy black so other then a thin line that looks like a crack you have to really look closely for the break.
The previous breakage was a small plastic pipe inlet for the overflow of the cooling system that is attached to the head.
My previous German cars had all sorts of black plastic failures and wished they used a different type of plastic
I am waiting for the day that the oil filter housing shatters while undoing it for a filter replacement
Why do they use such brittle plastic that obviously is affected by heat??
My latest breakage was my engine cover, tried to remove it to change the plugs and the front right pin would not pull out. I pulled and pulled albeit gently. It eventually came off but did so leaving a 2"x2" hole in the cover with the pin and surrounding plastic still stuck on the head. I subsequently reglued (fiberglass reinforced) that broken part back on using some West System 6-10 epoxy that I had around for my sailboat repairs. I did the repair on the underside of the cover and tinted the epoxy black so other then a thin line that looks like a crack you have to really look closely for the break.
The previous breakage was a small plastic pipe inlet for the overflow of the cooling system that is attached to the head.
My previous German cars had all sorts of black plastic failures and wished they used a different type of plastic
I am waiting for the day that the oil filter housing shatters while undoing it for a filter replacement
Why do they use such brittle plastic that obviously is affected by heat??
Newbie
Joined: Dec 2010
Posts: 10
Likes: 0
From: Toronto, ON
2021 C43 AMG Wagon
I had the same problem with the plastic engine cover breaking. I bought a new one from MB, about $100. They updated the part to be a bit thicker and stronger.
I think there was another thread where the poster recommended replacing the other part, as it's a common failure point:
https://mbworld.org/forums/c-class-w...ance-item.html
I think there was another thread where the poster recommended replacing the other part, as it's a common failure point:
https://mbworld.org/forums/c-class-w...ance-item.html
Thread Starter
MBWorld Fanatic!
Joined: Dec 2006
Posts: 1,105
Likes: 11
From: Toronto, Canada
2019 C300 Wagon; '75 Triumph TR6; previous: 2004 C230 6spd sold after 17 years of driving
Now that I had 24hrs cooling off period after being livid of breaking my cover and allowing the fiberglass and epoxy patch fully harden with clamps. I thought that I would share my finished repair.
The first 2 pics are the tinted epoxy/fiberglass reinforcement patch on the backside with the foam pulled back. If you look very closely at the last 2 pics there is a hint of the outline of the jagged 2" piece that shattered off. Since my car is not going to a concours I will save my $100 or more for a replacement cover. Wish I took a picture of the giant shattered hole through the cover as a before pic. West Systems epoxy is the best! (very strong, low odor, easy to work with and able to be tinted any colour, though it is quite expensive)
The first 2 pics are the tinted epoxy/fiberglass reinforcement patch on the backside with the foam pulled back. If you look very closely at the last 2 pics there is a hint of the outline of the jagged 2" piece that shattered off. Since my car is not going to a concours I will save my $100 or more for a replacement cover. Wish I took a picture of the giant shattered hole through the cover as a before pic. West Systems epoxy is the best! (very strong, low odor, easy to work with and able to be tinted any colour, though it is quite expensive)
Last edited by Boom vang; Apr 26, 2011 at 05:01 PM.
