I just bought a 1987 300SDL with 185k miles and there is oil in the coolant reservoir. It builds up pressure but the temperature is staying at normal range (80 degrees) even with the ac on. It idles fine and there is no misfire.
Im ready to pull the heads off and replace the headgasket but I dont have a shop manual for this car. Does anybody know where I can get one?
Mark

Hmmmmm......This is beginning to sound like a classic case here! Who wants to volunteer an answer?

Cracked head, for sure. Outside chance of a bad head gasket, but the classic failure is a bad head.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

what makes you say that? If it was cracked it would overheat wouldnt it?

Is the cooling system still under pressure 12 hours after you shut off the engine?

Can you read the head casting number near the #2 intake runner?

Oil in the coolant is reason enough to pull the head. When the head is out have it checked by someone who knows MB aluminum Diesel heads.

Try the FastLane link at the top of the page for your own copy of the MB shop manuals on CD. Use the forum search feature to find a link to an on-line version of the shop manual.

Sixto
95 S420
87 300SDL

See the 7600 posts to Peter's credit? He's been here long enough to know what excessive pressure in the cooling system means for an OM603.

Patience, young grasshopper, that's not far behind the other symptoms

Sixto
95 S420
87 300SDL

I drove mine for at least 15,000 miles with an ever-worsening cracked head (I was in denial for a while) and it never showed signs of even remotely overheating. Coolant loss and cold pressure in the system were the only symptoms. At first, it would only lose about a quart of coolant per couple thousand miles, but eventually got worse.

__________________
Keep everything as simple as possible-but no simpler--Albert Einstein

Definitely check for a 'hard' Top Rad hose after engine has been shut down overnight. That will indicate a likely cracked head. If it is soft and pliable, you may just have a leaking head Gasket.

While I agree that a cracked head or damaged Head Gasket are the most likely scenario's on a 603 engine with oil in the coolant, there are other possible explanations.
Has there been any Head work done by the Previous Owner? If so there may have been prior oil/coolant contamination that never got cleaned out.

As Habanero has said, if the problem is minor and there is no overheating, you could drive many miles before you have to pull the head. Clean out the Cooling System and see how long it takes to contaminate. That will give you an indicator of how bad the problem is.

Hardcopy Paper Manuals are getting hard to find but you may find one on e-Bay. You can also get CD copies there or at your M-B Dealer.

Congratulations on the purchase and Good Luck.

__________________
1991 M-B 560SEL Arctic White/Grey 99,000 Miles
1987 M-B 300SDL Ivory/Palomino 229,000 Miles (sold but never forgotten)
2006 Volvo XC70 Blue/Beige
1999 Porsche Boxster Arena Red/Savanna Beige
1986 Porsche 928S Goldweiss/Brown

I should clarify that I didn't necessarily mean to advise driving that many miles with a cracked head. One upper cylinder full of coolant and that's the ballgame. I think I may have been luckier than I should have been (if, of course, one can assume any level of luck when encountering a 2500 dollar auto repair).

__________________
Keep everything as simple as possible-but no simpler--Albert Einstein

You need to pull the head either way so pull it. If you are lucky you need just a head gasket, if you are unlucky you have a cracked head.

If the head casting number is 14 I will bet on a cracked head. Thats probably why the old owner dumped it.

__________________
1999 SL500
1969 280SE
2023 Ram 1500
2007 Tiara 3200

Well from your description, you've got a problem. Your head most likely has a crack...I'd go to a local reputalbe INDY and at least get confirmation. Then if the head is cracked you'll have to make the decision to replace or dump it, depending on how much money you've already put into the car. Great cars, bad heads on the SDL.

hi mark,
I have a similar problem. I I bought the alldata from diy.com. This was a wast of money. I think I get a CD from europe soon. After the repai of my car, You can get it. I work on my car right now. I shoot a lot of pictures about. Maybe, when You are interested, I can send them to You


Good Luck

Martin

Hiya gents. I'm a newby and not a gearhead. I'm not sure that I'm using the proper venue but here go it.
I've got oil sludge in my coolant reservoir.
I have .... 1. had a reputable MB tech (service manager) do all my mechanical
work.
2. he did a test to determine it WAS the head
3. head was taken to a reputable machinist ( who recognized the
head immediately and commented that he used to do a dozen a a year in the mid/late 90's) who said that they were difficult to
test since they can't magnaflex (sp) aluminum heads.
He found the head slightly warped but could still mill w/in specs
4. Radiator/ reservoir were flushed then reservoir was replaced
so that any residual residue (?) would be self evident in a
brand new tank.
5. All MB specs were adhered (torqued properly,valves,guides etc)

Within 500 miles after the head I had more oil in the new reservoir.
I had the coolant system flushed 2x a week apart
Changed the oil (I had been using Tella 15-40) but MB service tech 'speced'
20w50...... so I did.
1000 miles later I have as much sludge(if not more) in the reservoir as before the 'head' job.
I get a little white smoke under load and an oil puddle under the turbo
I lose a quart of oil every 700 miles
Don't overheat.... runs @ 80-85 w/ AC on
Have full power (injector pump rebuilt last year)
Since I paid for the machinist, mechanic and the dealership seperately
what recourse do I have
I'm assuming it's still the head.
HELP?

The new guy

Shouldn't have bought the 91 SDL in the first place. It is known to be a infamous 'Rod Bender'. Do a search on 'Rod Bender' and here and you will find a lot of bed side reading material. I think you are done for, I am afraid.

A replacement engine is in order. Good luck.

__________________
Not MBZ nor A/C trained professional but a die-hard DIY and green engineer. Use the info at your own peril. Picked up 2 Infractions because of disagreements. NOW reversed.

W124 Keyless remote, PM for details. http://www.peachparts.com/shopforum/mercedes-used-parts-sale-wanted/334620-fs-w124-chasis-keyless-remote-%2450-shipped.html

1 X 2006 CDI
1 x 87 300SDL
1 x 87 300D
1 x 87 300TDT wagon
1 x 83 300D
1 x 84 190D ( 5 sp ) - All R134 converted + keyless entry.

When the head comes off again, measure the protrusion above the block deck of each piston at the fore and aft edges. The pistons should be level fore-to-aft with a protrusion of something like 0.7mm. Don't quote me on that, check the manual. Pistons can rock side-to-side so there's no value in checking side protrusion. The rod bending nature of the 603.97x is such that the pistons bow forward. My avatar gives you an idea of how rods bend. If a rod is bent, expect the forward edge of the piston have insufficient protrusion.

If you confirm bent rods, options include a buying new/rebuilt short block with redesigned rods, fitting redesigned rod$ and possibly cylinder liner$, and retrofitting a 603.96x block. The latter means you lose displacement and more importantly stroke resulting in less off-the-line torque. On the other hand the 3.0 block revs more freely. Small consolation.

Sixto
87 300D