Hey everyone. I'm pretty new around this forum. I've had my 1992 300D for about 3 years, and now I'm having some serious issues with it.

Problem #1 (check this link for a thread I started on another forum) http://www.schumanautomotive.com/forums/showthread.php?t=8988 this started about 3 months ago, and got progressively worse ever since. My engine temp would fluctuate a lot. On a hot day it could not even maintain anything below 100*C (normal operating temp is 80*, it goes up to 100* during heavy load periods, such as a hill)
I noticed I was going through a lot of coolant. The engine would get hot, the coolant would expand and overflow out of the.... overflow and then the engine would overheat. I replaced the expansion tank, it's lid, and the thermostat. I believe the tank/lid combo helped retain the coolant for longer, but it would still overflow.

Problem #2 (link) http://www.schumanautomotive.com/forums/showthread.php?t=9162 I go out to start my car one day and.... nothin. The starter will make sound, like it's trying to turn the engine, but to no avail. The engine will not turn over at all, not 1/8 turn. On the other forum some members came to the conclusion that the engine might be hydrolocked and suggested I attempt to turn the engine via crank shaft. I tried that and was able to turn it, not very far due to space, but still, it was pretty easy. Then I went through the trouble of replacing the starter, after that the engine started and ran. YAY! right? No, wrong. We clean up after ourselves, take the car off stands, and wrap up for the day. Next day I try to pull out of the garage and nothing, same symptom as before I replaced the starter. Then I went through the trouble of replacing all the battery cables, having the battery tested, and cleaning the heck out of everything (connections and whatever else I can get my hands on). To no avail. Same symptom.
Then I get back on the crank shaft. It turns a few cm and then... nothing, can't turn it at all, not with two people on it.

Any advice, knowledge, tips, suggestions, ANYTHING!! will be appreciated.

Thanks and Hello,
Ben

On a gasoline engine any time hydrolock is suspected the first thing to do is pull all the spark plugs and see if you can turn the motor either by hand or with the starter. I would think the same would be true with a diesel. I would pull the glow plugs but others may have a better option. You dont want to force the motor to turn over without giving any fluid a placxe to go ie out the glow plug holes. Pull all of them and see which ones if any puke liquid when you turn it over and then you will know. Thanks

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83 300D 227,xxx miles, sold
86 300 SDL 130,000 miles, sold

You can also pull the injectors which might be less work in a 602. You'll need new heat shields when the injectors go back in.

Sixto
87 300D

so will doing this test tell me where the blown gasket is? assuming that it is hydrolocked and fluid comes out.

It will tell you which cylinders took on water and a general area of failure, If you get fluid you are done anyway. The head must come off. Thanks

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83 300D 227,xxx miles, sold
86 300 SDL 130,000 miles, sold

Correct - if any fluid is expelled from any cylinder, you have serious problems and the head has to come off. Also check the oil for any signs of coolant. If the engine won't crank, but will crank fine with the injectors or glow plugs removed, that's also a bad sign (again, I'd expect liquid of some sort to come out during cranking).

BTW - the links to the Boneheaddoctor / Lester (aka "Schuman") forum don't help. You can't view those unless you register at that forum and log in. You'd need to copy & paste the important info from those threads and post them here...

__________________
Dave
Boise, ID
Check out my website photos, documents, and movies!

ah, didn't know that about the Schuman forum. But I think I described it well enough... i hope... seeing how as we have a pretty good idea it's this hydrolocked deal. (btw, that's the big conclusion they came to on the other forum)
But, anyway, I'll take off the injectors (hopefully within a day or two, gotta pick up some tools, and I'm waiting for the heat shields still).
Do I take all of them off at once, and should I crank it using the starter or should I do it manually. Also, there are plastic covers (or something) on the injectors and some of them are broken, should I replace these? and what are they.

Thanks,
Ben

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1992 300D OM602

Ben

You can re-use the heat shields for a short time, if necessary. Since they are a one-time use, if you take it apart and find you need to do major work, I'd wait until you're all done before re-installing the injectors with new heat shields. I wouldn't re-use them long term though.



I would turn the engine by hand. The starter could, in extreme circumstances, bend a rod. If you have any significant liquid in the cylinder you should know pretty quick. If it's draining past the piston rings into the oil sump, you should be able to determine that via the dipstick.



The plastic shields keep dirt & debris out of the threads on the injector. For reasons that escape me, Mercedes no longer sells these plastic covers. They usually break while taking things apart. Don't worry about them.

My car is doing exactly the same thing. Great every day until one morning it won't crank. I took the cap off the expansion tank and it was pressurized. I hand turned the crank and when it got to the really tough cylinder, while puling (very hard) through this cylinder you can hear fluid being emptying into the crankcase.

Either the head gasket, or the head.

I've got new head bolts, now I'm waiting for the head gasket. Next wee I take it all apart.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Michael, is this the SDL that recently came together?

Sixto
87 300D

What fluid (besides oil) are you finding in the crankcase Michael?

__________________

Gone to the dark side

- Jeff

It is. Bummer.

It seems to have happened overnight. No overheating.
I have a #22 head.
I measured the head bolts for tolerance and reused them. Maybe I shouldn't have.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

I actually haven't checked yet. I've had other projects I had to finish first.

__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Nah, I'd be shocked if it had anything to do with re-using the bolts. I've re-used them on both my 602 and 603. You have to abuse the bolts pretty bad to stretch them beyond spec. I have replaced a couple with boogered-up 12-pt heads though. More likely to be a head gasket, or freak head failure. I'm very interested to hear what you find when it comes apart - please post a link to your thread, assuming you start one.

I assume you used a name-brand gasket set, chased all 27 or so head bolt threads with tap & die (both the bolt AND the block threads), and soaked all liquid out of the block? And used clean engine oil on the threads when installing? And used the factory 4-stage torque procedure with an angle rotation gauge, not eyeballing it? Lots of little things to go wrong if you're not careful...

Well I pulled the injectors and sure enough... water... out of the third cylinder. Looks like I'm gonna be pullin the head. I've never done anything like this before, on any car. I've never even taken off the valve cover.

My point is, is that I'm gonna need all the help and info I can get. What tools do I need to pull the head? What do I need to buy to complete the whole job? What things require replacement after disassembled (gaskets, etc.)? Anything I need to be particularly careful of/avoid completely/remember specifically? Anything I should look into or take care of while I've got everything apart? Trouble areas?

Hopefully I'm gonna be able to get someone who actually knows engines to help me out. I only have a couple weeks to complete the whole job, so hope I can do it.

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1992 300D OM602

Ben