91 190e 2.3 8V broken intake valve head replacement - PeachParts Mercedes-Benz Forum

clintard · #1 04-14-2014, 02:20 AM

91 190E 2.3 8 valve with 92,000 miles.

I purchased this car about 6 months ago and shortly after started getting oil in the coolant. I knew it would need a head gasket and probably need the head milled flat. I travel for work so the car rarely gets driven, and i have no had enough time at home to complete the job. Ive just been flushing the coolant and adding new until i got the time and money to fix it right.

Recently the water pump started seeping so add that to the list (probably my fault for continuing to drive it occasionally)

Driving down the freeway on my way home the other night and out of the blue heard a horrible clacking noise so pulled over. The temp gauge was about halfway between the 3/4 and 120C mark on the gauge. Oil was all over the exhaust side of the block as well. It would not start after cooling down.

Compression check showed 0, 30, 50, 90 from front of engine going towards firewall.

Pulled the head off tonight and this is what i found. I could not find the missing piece of the valve anywhere so i assume the piston shot it up through the head next to the valve guide. There was no damage to the piston, i cant even find a scratch on it. There was a really large hole in part of the head gasket that wasnt left stuck to the block or head as well. I assume that is where the oil was flowing into the coolant.

By the looks of things, i assume the guy who sold me the car changed the head gasket fairly recently. The exhaust, intake, and head gaskets all seem to be newer and i havent touched the head or cylinders so it seems someone already removed the carbon. The exhaust studs all came out of the head when i removed the nuts and were extremely easy to get out.

I assume the guy had a head gasket leak, changed head gasket himself without having the head ground flat, slapped it back together and either sold the car as soon as he did it or noticed it leaking again and decided to sell that car. When i bought the car it had brand new green coolant in it, and about 2 weeks after i bought it is when i noticed the oil getting into the coolant.

The car has always ran extremely well and had no noises whatsoever.

3 questions:

What would you think caused the intake valve to break off like that?

What would be the best/most economical route of replacing this head with another and doing it right?

Is this a good deal? Mercedes 190 E 2 3 Rebuilt Cylinder Head | eBay

more pictures: imgur: the simple image sharer

Hirnbeiss · #2 04-14-2014, 07:30 AM

Probably fluid in the cylinder. Liquids are incompressible - number one cause of valve failure in large recipricocating compressors. Otherwise, maybe a gasket chunk helped break the valve, which then helped break the cylinder head. It looks like there is also a little damage on the cylinder wall.
Before rebuilding this one, with its green coolant and water-in-the-oil history, I'd look for a used motor to swap in.

duxthe1 · #3 04-15-2014, 02:04 AM

That's a burned exhaust valve. It didn't break it melted. They'll do that when run without enough coolant.