300SD head gasket

I have an '84 300SD that's been losing coolant. I've checked for loose hose clamps and tightened a couple but the problem remains. In what appears to be a string of bad luck on this vehicle, the starter was replaced recently and the mechanic noticed that the head had been leaking in the back driver's side corner. I've owned the car for 18 months, it has about 143K miles and have not had it overheat. I'm aware that the aluminum head six can have head problems but thought that this was unlikely in the iron head engine. Is this common? The repair folks I go to though not a Mercedes shop do have some experience w/ with the diesel MBs as well as others so I trust their observation. I'm asking of the wisdom of the group... Is this an indication of other problems? Or, is this a fluike in the reputation of a reliable durable vehicle? The shop suggested that it may be a time to check other things on the headguides, valves.. If the head is warped I assume being a diesel there isn't much latitude for milling..

Reply to
JackG
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You should satisfy yourself that ALL hoses are OK before undertaking anything with the cylinder head or head gasket. There's a coolant hose in the driver's side rear corner of this motor - if coolant is what's actually leaking there rather than lube oil oozing from the valve cover.

Leave the cylinder head alone unless there's coolant in the engine oil or engine oil in the coolant! And the motor's valve guides should not need any work at this point - that's, IMHO, just the muttering of someone who doesn't KNOW what to say about the current problem. Find another shop.

Suggest you carefully look at the radiator, water pump, auxiliary water pump (for the heater), heater and all hoses. A coolant leak will show itself soon after a hot engine is shut down for that's when the cooling system pressure is at its highest.

Cylinder head gasket failures have some typical symptoms: Engine overheating, oil in the coolant and / or coolant in the oil, white smoke from the exhaust as coolant is burned out of the rapidly heating exhaust after a cold start.

Your motor doesn't have any of these - or you would have said so!

Reply to
T.G. Lambach

Hi Jack,

If your in the Los Angeles area I know of two very good independent MBZ service shops that service MB's only and nothing else.

Reply to
Martin S.

Reply to
JackG

Martin,

Thanks for the offer. But, I'm > Hi Jack,

Reply to
JackG

for what it's worth. I've had a coolant leak a few weeks ago. Thought it was the head gasket, pump, etc, etc. Finally thought to check the radiator cap... the rubber seal had badly deterioated, allowing the coolant to leak out the overflow when pressure was building.... replaced the cap and had no problems since.... could be as simple as that.

cheers, guenter

Reply to
Guenter Scholz

It happens. Your head does sound bad if there is no visible coolant leak and a verified head leak. It's very very rare but it happens.

So get the head gasket done and the head rebuilt. It'll be like a new engine.

Reply to
Richard Sexton

Al small leak is difficult to find. It usually only leaks if the engine is warm and the cooling system is under pressure. The water will the evaporate which makes is hard to find the leak. The best way to find it is to pressurize the cooling system with a cold engine by using a special pump, do not try to use a compressor. The engine has to be really cold, not just cooled down. Very common leaks are; water pump, radiator, hoses and metal tubes. Never pull/rebuild the head if you don?t know where it is leaking. There are much less expensive ways to check a head than taking is off. Valve clearance will tell how much the valves and seats are worn. If in doubt a mechanic can use a endoscope to look in the engine without taking the head off.

Reply to
RobP

had a leak in a cavalier.... put in one of those 'sealing' tablets... worked great... no more problems for over 2 years. Of course the leak was 'tiny' needed rad fill up every couple of weeks which, of course, my daughter never did until the car overheated :-/

cheers, guenter

ps I guess it depends on the age and condition of the car

Reply to
Guenter Scholz

Just don't try minute rice :)

Reply to
me

No, but I did use minute rice once many years ago to clean out the cylinders in my VW van .... just poured a handful into the intake... scary :-)

Reply to
Guenter Scholz

How about Westbury, Long Island? I know a great MB shop there.

Reply to
Gogarty

Minute rice? Wouldn't that clog things up?

Reply to
weelliott

no, the rice grains are just hard enough to losen carbon deposits around valves, etc but won't hurt the cylinders.... they fly out the manifold

cheers, guenter

Reply to
Guenter Scholz

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