Hi All,
My dad has an 87 300TD that started overheating, took it to a shop that pulled off the head which showed a couple of visible cracks. At least one piston top looks as though something got caught in the combustion chamber and took a pounding. I think the mileage is close to 200K, brakes and front end were just gone through. Is it worth putting the money into a new/rebuilt head and possibly rebuilding the block as well? What are some good avenues to pursue to find decent prices for the parts if it is worth it? What about a complete long block?
Many Thanks,
Matt

If the rest of the car is sound then I'd opt for a new head. Later designs of the head have pretty much eliminated the problems of cracking unless you really abuse it. One of the members of this forum is our resident expert on head replacements for your engine (OM603). Do a search under the name gsxr and visit his website. He's done lots of posts about the cracked head problems on these cars and it should give you pretty much all you need. As the owner of an '87 I can tell you they are great cars and worth saving if the rest of the car is solid.

__________________
LRG
1987 300D Turbo 175K
2006 Toyota Prius, efficent but no soul
1985 300 TDT(130K miles of trouble free motoring)now sold

The '87 TD is a rare car (2000 made) isn't it? Unless it's a rust bucket or overall poor condition, I think it would be worth rebuilding the engine with a new head.

According to Nitske's book, MB only produced a little over 2000 '87 TDs. As to how many of those made it here, is still a mystery. Everytime I drive my (ok, wife's), '87 TD I still get impressed. It is just something one has to experience to fully understand. As to "is it worth it or not". I look at it this way, it will cost a hell of lot less to rebuild than it is to find another one of these. You know the car, why start all over again with a replacement. These W124's have many of the same features found on today's cars. You have an airbag, ABS, power seats, power tilt sunroof, 4 wheel disc brakes, 4 wheel independant suspension, etc. Both of my TDs are as reliable, if not more (no electronic gremlins) than todays cars. So, "worth" is subjective. Speaking purely about cash value, then it would make no financal sense, considering the age of the car. Then again, if we all bought cars that made abolute financal sense, we would all be driving the cheapest cars on the road.

__________________
1999 MB SL500 (110,000 mi)
2004 Volvo V70 2.5T (220,000 mi)
2014 Tesla Model S 85 (136,000 mi)
MBCA member

Thanks guys for a little different perspective that I hadn't thought of. The car has been in the family since 30K and just had new tires as well as the rest of the aforementioned and, since it's a So. Cal native, there is no rust. I'll try to keep you informed as to what the final decision is.
Matt

Well I just found out I can get a good running complete engine for $1500, so at this point that will be the road we're going to travel. I'll keep you posted on how it goes.
Matt

When you have it secured, let us know where you got it.

Thanks,
Sixto
95 S420
87 300SDL

A little update and question. I'm going tomorrow to "hear" the engine run. Is there anything in particular I should look/listen for when checking this engine out? It's in a wrecking yard so I'm guessing the car has some sort of damage to it. Would checking compression be a good place to start, and should I ecpect the yard to do it?
Thanks,
Matt

You'll want to do a leakdown test which is more likely to catch head cracks than a compression test.

If it's hooked up to a cooling system, see if pressure builds before the thermostat opens. If they run it without a cooling system, maybe you can rig a bicycle tube between the upper and lower hose fittings and see if it inflates.

Sixto
95 S420
87 300SDL

I'd be nervous about buying any used 603 engine unless it was in a car I could drive before buying. The pressure in the cooling system with a "micro crack" won't appear unless the engine is loaded, like a 0-60 run at full throttle. Only major cracks or leaks will show up at idle or revving with no load.

Anyway, you can get the "improved" head from a 3.5L engine used for about $1000, plus another $400 or so in parts, plus labor (or some special tools if you DIY). A brand-new head is usually $1800-$2000 but there happens to be one on eBay right now for $1500. Don't bother fixing the old head or buying another 86/87 head. Very strange about the piston top being banged up. If the piston damage is not bad, and the engine is otherwise in good shape, I'd fix it rather than replace it. Or at least PLEASE keep the old engine around as you may need it for parts!

Prices for dealer rebuilt long blocks are in this PDF file (click link below). Note that one bonus when buying a dealer engine is that the warranty is valid at all MB dealers nationwide:

http://www.meimann.com/docs/mercedes/OM603_rebuilt_engines.pdf


BTW - I strongly recommend keeping the car and fixing it, unless you simply don't want it any more. Buying a different used car is always a gamble and since you've owned this a long time it's wiser, IMO, to repair it. If not I'll give you $500 to take the junker off your hands though.


Photos of my head R&R job are on my wbesite, click the "www" button at the bottom of this post...

HTH

__________________
Check out my website photos, documents, and movies!

oh yeah - I believe there were about 2500 sedans and 1500 W124 wagons imported in 1987 to the USA, plus a whole lot of SDL's with the same engine. All of them had the flawed cylinder head, where the casting number below the #2 injector is 603-016-xx-01... if "xx" is 14 that's an original 86/87 head. If it's 17, that's a good head from a 1990-95 3.5L, and the brand new heads are either 22 or 23. There were a total of SIX different heads and SIX head gaskets... MB re-designed them five times before getting it right!

__________________
Check out my website photos, documents, and movies!

Well.... I made the trip up to All Star/5 Star(Sun Valley) to hear/look at the engine and....it started right up, ran smooth, everything looked original. The interior, just for kicks, looked very well taken care of and there is a 90 day warranty on the engine. I didn't get a chance to read the last post before I left, so I wasn't able to verify the casting #'s. There were 210K on the odometer and the engine looked fairly clean(hadn't been cleaned by the yard), so I'm inclined to swap it out. The price of $1500 is cash with exchange and I really don't have a place to store the extra engine anyway, even though the aspect of having extra parts around is appealling.
Matt

In that case I would at least remove the turbo and injection pump before turning in the core engine. If the vacuum pump is newer on your engine, swap that over too. Either way you need to make sure the vacuum pump that will go on the new/good engine is the improved version with four Torx screws in the front cover - if not, replace that ASAP, before putting the car back into service! The old ones normally fail by ~200kmi and the flawed bearing design dumps parts into the timing chain, causing thousands of $$$'s damage if you're unlucky, or best case requiring you to pull the oil pan to fish out bearing parts after replacing the pump...!

here's a photo of the "good" pump:

http://www.meimann.com/images/mercedes/head_gasket/vac_pump1.jpg


I'd also yank the intake manifold off the new engine, replace all the plastic clips & foam buffers for the injection lines, as they WILL be shot at 200kmi. Cost is minimal ($25?) and to see what it prevents, look at this URL toward the bottom:

http://www.meimann.com/images/mercedes/OM603_injection/

__________________
Check out my website photos, documents, and movies!

Ron's European,Cocoa, Fla. has an 87 300D with 140K, engine reportedly great shape. Car was wrecked, engine not touched.

321-452-9097