Looking to buy a 1980’s MB S Class diesel. - PeachParts Mercedes-Benz Forum

cgryphon · #1 10-28-2004, 02:34 PM

Looking to buy a 1980’s MB S Class diesel. I’d like to get some pros/cons, differences, experience, etc.

I've spent the last couple of days doing the search thing and lots of reading. Looks like an active and well spoken forum. Thanks for that. I'm forming opinions from what I've read, but thought I would ask my questions specifically.

Do you like the 5 or 6 cylinder models?

SD vs. SDL?

Early 80’s or late 80’s?

I’m looking at an ’83 (5 cylinder) SD Cream w/ Tobacco Leather with about 115K miles – or – an ’87 (6 cylinder) SDL Silver w/ Blue Leather with about 135K miles.

Any specific problems I should be looking for in this mileage range (timing chain, brakes, suspension, etc)?

All opinions appreciated!

Thanks,

cg

boneheaddoctor · #2 10-28-2004, 02:51 PM

the 5 cyl is bullet proof (617) the 6 cylinder is a head cracker ( 603) avoid cars with 014 in the casting number in the middle, higher numbers are best, a 016 or 017

try a search on 603 alluminum head cracking.

I am not a 603 expert.

KCampbell · #3 10-28-2004, 03:52 PM

The SDL is longer than the SD, which may be nice if you want extra rear legroom.

The 603 engine is more advanced in many ways, hydraulic lifters, cross flow engine (inlet on one side, exhaust on the other), aluminum head, higher power output.

The 617 is bulletproof and very simple to work on. Because inlet and exhaust manifolds co-exist it's much easier to get to the injectors, glow plugs, injection pump, ALDA, etc because there's no inlet manifold hiding everything. A number of 603s seem to have worrying wear patterns on the fuel lines running to the injectors where they have rubbed aginst the inlet manifold, and there's the whole cracked head issue. The 350 SDL has another potentially troublesome motor - search for "rod bender" for examples.

Apart from the engine there is not much difference assuming you're thinking of the '81 and later 300SD, both the SD and SDL are 126 chassis cars, so most of the non-engine systems will be very similar.

I purchased my 1985 300SD two weeks ago, with 174K on it. I was considering the same choices as you, but went what I felt to be the "safer" route.

After I replaced the fuel filters and tweaked the ALDA, both 10 minute jobs, it runs very well. Acceleration off the line is completely sufficient for day to day driving, and it cruises smoothly and easily at highway speeds.

I have replaced the drivers seat spring base and rubber hair mat, belts and I'll replace the shocks this weekend - all wear items that won't be much different whether an SD or SDL.

Kevin

D.Blake · #4 10-28-2004, 03:57 PM

I have a fairly good example of both styles of 81-87 S Class. The 83 has the 617 Cast Iron head engine. The SDL has the AL Head engine. Some Pros and cons compared to each other:

81-85 SD
Pro:
Bullet Proof engine (almost) - Cheaper to replace lots of used/rebuilt engines;
More room to work on in the Engine Compartment;
Shorter body, a little more responsive to the road;
Simpler to work on sun roof
Cons:
For the 83 only - single point master locker - Driver's door;
Valve adjustment required ever 15K miles;
Engine is less efficient than the 603- poorer fuel mileage, less power (120hp, about 23 City, 27 Hwy);

86-87 SDL
Pro:
Longer body - lots of back seat leg room;
More efficient engine (148Hp, about 24 city, 30 Hwy);
No valve adjustment necessary;
Extendable steering wheel (on most)
Built in Alarm (when working)
Recirc button for ACC on Dash (comes in handy when passing a Dairy Farm!)
Serpentine Belt;
Vent style sun roof

Cons:
EXPENSIVE Engine when replacement is necessary;
Whimpy head, subject to cracking when overheated - most 14 heads that haven't cracked, will;
Built in Alarm (not working)
Working on the sun roof...;
Expensive AC compressor

I am sure there are more but these have been the ones who have come to mind. My preference is the SDL, but I wouldn't want to park it just anywhere!!!

#5 10-28-2004, 05:41 PM

I like my '86 SDL. It's the origional 014. I haven't had problems and I hope I don't. I have 166k miles. It has great power and most of all it's in great condition. You should look at the SD's or the SDL's. The 1985 300SD is a great car. The '86 300SDL is a bit longer. It's a fabulous car that will get many heads turning. You can pick problems from a dime and a dozen. Just make sure that whomever you by your car from has a paper trail of service records. That's the best history you can get on your potential car... Good Luck!

cgryphon · #6 10-28-2004, 08:45 PM

Thanks for all the well thought out responses so far. I’m leaning towards the 83 SD, mostly because I really like the Tobacco Leather, all other things being equal. Just can’t really get into the blues and reds that I’ve seen.

One of the cars I'm interested in is located in the Miami area. Anyone know of any good sources for PPI in the area?

BTW, anybody watch this one on *bay?

[

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=6330&item=2494685140&rd=1]

Looks like the first buyer fell through, but number 2 in line got it on a Buy it Now. Pretty tall cotton there, I’d say.

Thanks again for the time and responses.
cg

D.Blake · #7 10-28-2004, 09:31 PM

CG,
That car is almost exactly the color sceme of my SDL. My interior is a lighter brown (Palamino I think). Mine does not have the headlight wipers but does have the euro headlights. Much better looking IMHO. Of course mine has just a few more miles on it, BUT it does have the updated 22 head. I have had 2 240Ds, my SD which my son now drives. The SDL is one of the finest cars I have ever driven. It has class and the look of "old money", kinda like an old Rolls. The car cruises beautifully on the Interstates at 75 or above. The SD is a good car and can be less of a headache, but now that I have the SDL, I doubt I could go back. Good Luck in your search!

Hatterasguy · #8 10-28-2004, 10:59 PM

Drive the SDL before you buy the SD. The 603 is the first modern diesel MB put into their cars, it has more in common with a 606 then a 617. Also do a search on my posts I pretty much have coverd every common W126/SDL problems.

Read my vac pump post.

Also check the oil cooler lines for rust on the lower fittings.

Check the head casting number a "14" isn't bad but a higher number is better.

Bring what ever car you want to buy to a good shop that knows these or the dealer and have it checked out.