300E Headgasget
 

I have an 89 300E (3.0) that is leaking oil at the rear of the headgasget (under the intake) My question is that since these engines are prone to headgasget problems is there procedures to lengthen the life of the gasget ? Also, has anyone done this at home that could give me some tips. Do you really need a hoist ? What about head gasget choices ?
Thanks,
Robert Davis

I just pulled the head off my E320. I recommend using a hoist. Luckily, I was already set up in the garage with a cross-beam and come-along. I just lifted the head and pushed the car away. With both manifolds on, I'd say the assembly weighed 150-200 pounds.... too heavy and difficult to jostle around in the engine bay. It was too much trouble to remove both manifolds (couldn't... an intake bolt was overtorqued by the manufacturer!).

There is nothing you can do to postpone the repair or lenghten the live of a defective head gasket.
Make sure you get an OEM gasket. Stay away from ''jobber'' type of gasket, unless you want to go ,through the job again in a few months.
I've done mine years ago and took the head off without the intake/exhaust. it's heavy but doable without a hoist.
While the head is off, I would have a serious look at the valves, valve guides/seals. It is the best time to have a job valve done since it is the same work/labour involved.
JackD

Kestas offers good information, but it is for the M104, two cam engine, not the M103 single cam as is yours.

I pulled the head on my M103 like yours and did it as JackD did his. The head is aluminum and weighs nothing. For me it was MUCH easier leaving the intake in place. There are so many connnectors that are 15 years old and prone to breaking that it will save lots of trouble by leaving it in place. You will have to get underneath for a few of the intake bolts, but with a proper toolbox full of extensions, this will be no problem.

There are a few things you must be aware of such as how to deal with the timing chain tensioner, and how to properly put the rocker arm assemblies in place without stripping holes, but we can get you through all that. There is also a bit of a trick to getting the upper timing cover in place so that it doesn't leak.

Also, I would not even dream of simply replacing the head gasket without doing a valve job with new valve guides while you have the head off.

A great machine shop for doing the valve job properly and without gouging the price is "Bailey Crankshaft" in Dallas.

Good luck,