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300SDL

I have a Beautiful 1987 Black on Black 300SDL that my nephew overheated somehow a couple of years ago (his version of events doesn't add up, but whats done is done). The car has started and run, but would overheat quickly, and had a rough idle since the overheating. It's apparent either the head is cracked or warped, or the head gasket is blown. Anyway, I have not done anything with the vehicle, as I had purchased a new vehicle a couple of years ago, but planned to attend to the issue at some point. Anyway, after about a month, since last I started it, I went to start it today and it would not turnover, it would simply attempt to turnover and then the put a huge drain on the battery. It is definitely not the sorta feel I am used to when a starter is bad or when the battery is low (which it isn't). Does this mean my engine has seized or has something else seized? Can I recover from this, or is it most likely this means the engine is shot, and must be completely rebuilt?

Reply to
Glenflow55
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Those motors last FOREVER if you dont overheat them. Its probably toast. Maybe the head gasket was leaking and now the cyliders are rusted and the rings are stuck. I would pull the head to see what is going on and make a decision from there.

KH

Reply to
Kevin in San Diego

I'd guess that this is the same thing that happened to my Ford Diesel truck many years ago.

Blown head gasket, or cracked head, left to sit will fill a cylinder with coolant. You simply can not crank an engine with a liquid filled cylinder.

Just my 2 cents.

Reply to
Larry Davick

May have a hydraulic lock.

Coolant may have leaked into one cylinder from, as you say, a busted headgasket or cracked head. If the engine turned at all, this cylinder was soon in its compression stroke and, as we know, liquids don't compress so the engine's rotation stopped. Or, if the engine didn't turn at all, then one or another piston is seized and the whole thing must be disassembled.

In the happier event of a hydraulic lock, removal of the glow plugs will allow the trapped coolant to escape when the engine is cranked, or, less happy, confirm that the engine is, in fact, seized.

Reply to
T.G. Lambach

I would just pull the head and see. Either that or call a wrecker to junk it. KH

Reply to
Kevin in San Diego

Curiousity from another OM 603-er here... how much liquid would be left in a cylinder that is hydro-locked once it has gone to TDC (and back?) with the glowplug removed? What kind of space is left in the cylinder/prechamber with the piston at TDC, and is it small enough that any water left in there after a crank without glowplug would not hinder starting (and simply evaporate once the engine got running)?

I hope my 87 300D never overheats! I better fix that vicious fan clutch and find out where my slow coolant leak is coming from (going to)!

-Mike

Reply to
Mike "Rotor" Nowak

Cooling is vital! Never skimp on cooling. KH

Reply to
Kevin in San Diego

I have an engine & transmission sitting on a pallet ready to ship if you're interested.

Let me know.

Reply to
Kevin L. Bray

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