1988 190 2.3 spark plug problem.
 

Good morning!

I have just begun to renew my 1988 190E 2.3 with 100,000 miles.My kid drove it last and unfortunately it overheated on him so it has been in the garage for some six months.

In removing the spark plug wires, the two rear ones broke off. Most of my Benz repair experiences have been with my W124 Station wagons, a 91 300TE and a 95 E320, so I've never really seen a self destructive spark plug arrangement like the one in this engine. From what I've read it looks like the best way to deal with it is to break the plug and be careful so as not to allow any dirt into the cylinder. I would appreciate any words of wisdom from this august site.

I've not found any evidence of head gasket failure but do plan on replacing the valve stem seals... and now wires as well.

I'm not familiar with this setup, are the plugs in a well the diameter of the wire or sort of an open depression? Breaking the plug ceramic would work, just be sure to use compressed air to blow out the broken bits before the shell is unscrewed.

Are you changing the valve stem seals because of the overheating? I'd hold off until the actual cause is found as stem seals are not related to overheating.

The best way to test a head gasket combustion leak in to coolant is to pump air into the cylinder ( TDC with both valves closed ) and look for bubbles in the rad.

Thanks!
 

For taking the time to answer.

I thought about breaking the plugs and blowing out the muck before unscrewing the plugs out...so I guess I'm on the right track.

I am changing the seals because of high oil consumption. Actually I have no evidence that the head gasket is blown, however, I was thinking of replacing it just for the mechanical practice. There is no oil in the coolant and no coolant in the oil.

Again...Thanks.

nestor98, I would forget about replacing the head gasket for practice. Better to diagnose why the engine overheated and fix that first. What do you mean by "self-destructive spark plug arrangement"? I take it you have verified the engine didn't seize from the overheating episode?

Once the engine is running again I recommend getting it up to temperature, then change the oil.

Ferdman!
 

Good to hear from you.

About two years ago I changed the plugs and wires on this 190e. I did not know then that wires with plastic ends was the WRONG way to go. Seems that when an engine overheats (and by the way, it was due to a thermostat failure) the plastic ends will melt (self destruct) inside the spark plug holes...I did not know that would happen , now I have to break the darn things and hope to be able to get to the plug ends.

O.K. I will forget about the head gasket replacement, I did get from Peachparts new oil seals. It has been burning quite a lot of oil (about a quart every 300 miles) and everything I've read points to worn out seals. If you have any words of wisdom???

Wish me luck!

A dremel with a small cutter will make quick work of your melted in the spark plug plastic. Once out change the tip and polish/cut the rest out.

nestorb98, I have never replaced valve stem seals so I can't provide any advice with that job. With that much oil consumption it's a good idea to replace the valve stem seals.

Recommend buying Bosch or Beru spark plug wires. Apply a light coat of dielectric grease on the inside of each rubber boot to facilitate future removal. I apply a small dab to a Q-tip, then smear the dielectric grease inside the boot.

changing the valve stem seals should not be a big deal at all on the 2.3... on the six valve closest to the firewall is a pain because there's no access with off the shelf tools.... do a search... it helps to have a compressor and a special tool to guarantee that you are at TDC .... sorry i can't remember all the details, but i have done it twice.... you should see you consumption drop dramatically.