Considering purchase of a 1987 300D, what to look for? - PeachParts Mercedes-Benz Forum

Crazy_Nate · #1 07-21-2009, 09:13 PM

Hi guys, I've had my eye on a '87 300D, but to be honest, I don't really know much about the vehicles (weaknesses, specs, etc), so, I'd like to educate myself before the car is looked at. My girlfriend is going to look at the car before me (I'm not in the area), and she'll take pictures for me to inspect.

What engine is it (OM603?) Are there any "troublesome" engine numberings / castings?
What is a typical yearly maintenance routine (belts / valves / glow plugs / nozzles / just oil changes / etc)?
What kinds of long term maintenance things should I be aware of?
Is the W124 chassis prone to rust? If so, what areas should I look at?
How does the climate control system function? Is it automatic or manual? Anything to look out for there?
Is there anything I should be aware of coming from a W123?
Anything else I've missed?

Thanks for the help,

Nate

1stimer · #2 07-21-2009, 09:28 PM

I hate to post when my experience is limited to reading the forum, but I need the practice so I can try and help the regulars that might get tired of answering the same questions. I think much of this information can be had by doing a search or two.

I also think this is a very desirable car for its power, and I believe it was the fastest mercedes diesel until 1998's turbodiesel.

I think the typical W123 vs. W124 repair cost argument goes something like... the 124 is more expensive to maintain and more difficult to DIY, but there is a wealth of knowledge and expertise here so things can get done with only your ability as a DIY'r and access to tools, parts, money, and time to limit you.

I'd say weak points are the cylinder heads and AC. I think the #14 head is the most prone, but depending on mileage may have been replaced.

I think AC systems are problematic in most ACC equipped MB's.

Sunroof repairs can be expensive.

Rust seems to be the real killer, so yes I think it's important you examine the car closely and even more importantly pay the going rate for a qualified person to give the car a thorough inspection.

Hope I didn't make too many mistakes. Good luck!

Crazy_Nate · #3 07-21-2009, 09:54 PM

Sorry for all the general questions, I just felt like I didn't know where to look. I'll definitely have a mechanic look at it before I hand over any money. I'll definitely look at the head. In the meanwhile, I'll poke around on the forum.

Thanks for your time

David Wilson · #4 07-21-2009, 10:00 PM

Look for excessive cooling system pressure. Sign of head or gasket failure.

Check for excessive blowby in the crankcase (pull the oil fill cap while running) Sign of bad rings.

Look for white smoke in the exhaust. Another head problem indicator.

Do the lifters "tick" excessively. If so, it will bother you later when everything else is fixed.

Bounce the rear end and listen for squeaks (carrier bushings)

Run the heat/ac selector through the cycle. See if the air comes out of different vents as it should.

Check the sun roof operation. Expensive to fix.

Check the jack holes for rust. Look very closely.

Check the under body for rust. You're in the rustbelt.

Operate ALL the windows to check the mechanism.

Pay attention as to how the tranny shifts. Does it shift crisply, or does it slowly slide from gear to gear. Crisp is better.

Check all of your rubber suspension components for newness. If they are original, they need to be replaced. 22 year old rubber is past due.

Check any repair receipts to give you an indication of how thorough the previous owner was with the maintenance.

I'm sure there are many other things to look at that are no different than any other 22 year old car. I wish I had checked some of the ones I listed prior to purchasing my 87 300d.

After you read this, do a search and you will find most everything you need.

Jeremy5848 · #5 07-21-2009, 11:10 PM

The '87 300D is a joy to drive. More powerful and better handling than the older W123 cars with their less-powerful OM617 engines, more fuel-efficient and aerodynamic, the '87 300D (W124, OM603) was the first "modern" Mercedes diesel. The body style was copied by almost everyone and still looks "new" today. A typical car will get 25 MPG around town and 30 MPG on the road. YMMV.

Mercedes started selling 124 gassers in Germany in 1985 and brought them to the USA in 1986. For 1987 the OM603 diesel engine was introduced. The engine came with an alloy head that was (and still is) more susceptible to cracking if the engine is overheated than are the older iron-head engines. Improvements were made to both the head and the head gasket and the later versions were sturdier but it is still wise to keep an eye on the coolant temp gauge and not "try to make it home" if it starts to climb above 110C or thereabouts.

The oldest head has a part number with a "14" in it, later models were "17" and "20" and the last one had a "22." I would not necessarily avoid a car with a #14 head but given a choice, take the later version. You might consider using as a bargaining tool the possession of a #14 head. My car has a #14 head and I have no problems with it. However, the cooling system is in good condition and I keep an eye on it.

I have never heard why Mercedes dropped the 603 engine after the 1987 model year. It may have been because of the head problems or because of tightening smog regulations. In about 1990 they came out with a version that had a 5-cylinder turbodiesel, the OM602. The last W124, in 1995, had the OM606 6-cylinder normally-aspirated engine. As the years passed, the W124 got more and more electronics. The earlier models are therefore simpler and easier to care for.

There are a number of things that are easy to overlook but very expensive to repair in this car. They are: cracked head or blown gasket, suspension (under the car, problems are easy to hide), climate control system (sellers always say "it just needs to be recharged"), sunroof (the W124 came with the first slide/tilt sunroof and there were some design problems). These items can amount to thousands of dollars. Each. The cruise control is another common failure point but is less expensive to repair. You can get a rebuilt "brain" for about $300.

On the other hand, there are parts of these systems that you can fix yourself. With your own labor and also saving money by buying from FastLane, you can fix some parts of the suspension and the climate control yourself. The sunroof is a bigger challenge, not a DIY job for most of us, but you can live without it. You can change the oil and the fuel filters and the glow plugs yourself. You can replace light bulbs and patch broken wires.

I am seeing many W124 gassers (300E) in the junkyards now. Since the body of the gassers is the same as the diesels, this means lots of inexpensive body, interior, and trim parts are available.

The W124 chassis has far more in the way of creature comforts than the older cars; this also means more to repair. The '87 300D has ABS and a driver's air bag. It has power seats (with driver's seat memory) and retractable rear headrests.

Some people are good at repairs, others avoid them like the plague. This is a personal choice that you will have to make for yourself. If you have to hire someone to do repairs for you and pay full list price for all the parts, you will quickly learn why we say that there is no such thing as a "cheap" Mercedes. You can save at least half by learning to do the work yourself.

The '87 300D has the 722.4 4-speed mechanical automatic transmission first introduced in the last W123 cars. It is a good transmission and is generally very reliable. Lifetime is usually 200,000 miles or more. It is about as expensive to overhaul as most other automatic transmissions and is not a DIY job for most of us.

Much more information is available here via the search function. Good luck with your shopping. Have a professional inspect anything you're seriously thinking of buying. A hundred bucks will save you thousands of dollars of grief (ask me how I know).

Jeremy

Crazy_Nate · #6 07-22-2009, 03:46 PM

Thanks for the insight guys, I'll have my girlfriend write down the head casting number. Is there an easy way to describe to her where she can see it from? She's not too keen on engine components and I'm not too familiar with the layout yet. Is she going to need a mirror to see around anything?

If the preliminary photos and questions go well, I'll have it checked out by a mechanic. Are there any specific things they might not normally do that I'll ask them to look for? I don't mind paying a little more to have them check the pressure in the A/C system, check the coolant pressure hot and cold, maybe even do a compression test..? That should be worth my money, correct?

The car is a single owner car and is priced right about what I would pay for a solid vehicle ($5k). I expect a rather large list of documented repairs in it's long history.

babymog · #7 07-22-2009, 04:51 PM

The price is on the high end. They are desirable cars among the knowing, but don't command much of a selling price.

The 603 was dropped largely because of marketing. There wasn't much demand in the US for diesels during that era (thanks GM). And in the '90s, the smaller engine was put in the 124 so that it wouldn't out-perform the flagship S-class diesel. A very common tactic among German marques.

Jeremy5848 · #8 07-22-2009, 05:32 PM

Quote:

Originally Posted by babymog

. . . The 603 was dropped largely because of marketing. There wasn't much demand in the US for diesels during that era (thanks GM). And in the '90s, the smaller engine was put in the 124 so that it wouldn't out-perform the flagship S-class diesel. A very common tactic among German marques.

Thanks for the explanation, Jeff.

odie · #9 07-22-2009, 05:33 PM

my #14 head has 478,000 miles on it.

Jeremy5848 · #10 07-22-2009, 05:41 PM

Quote:

Originally Posted by Crazy_Nate

Thanks for the insight guys, I'll have my girlfriend write down the head casting number. Is there an easy way to describe to her where she can see it from? She's not too keen on engine components and I'm not too familiar with the layout yet. Is she going to need a mirror to see around anything?

The head number is cast in the aluminum. It is on the left (driver's) side of the head and almost exactly under the air pipe that crosses over the valve cover. You don't need a mirror but a bright flashlight will help and hope that there's not too much oil and dirt. You have to look between the injector hard lines and see a little bit of the number, then shift your view and see a little bit more. The number should be 603 016 xx 01 where xx is the head revision number. AFAIK, the choices for "xx" are 14, 17, 20, and 22. The "603" means it was first used in the 603 engine; the "016" means it is part of the air intake system, and the "xx" means the revision number. I forget what the final 01 is and it could be some other number too.

Jeremy

Bio300TDTdriver · #11 07-22-2009, 06:11 PM

You may want to read this.

Wodnek · #12 07-22-2009, 07:28 PM

I have 2.
87 300D
87 300TD

Both of mine have the 14 head. The guy that sold me the 300D told me to change the belt and belt tensioner every 3 years, weather it needs it or not.
I have heeded his advice. one has about 225,000 and the other 210,000 miles.

These cars can turn on a dime. With good tires and suspension components you can make a u turn at 35 mph. These have lots of rubber bits in the suspension. If it doesnt have nice tight handling, some of these rubber bits need to be replaced. None of them are expensive, and most are not difficult to replace yourself. In the rust belt the rubber parts last a long time.

Rust is not near the issue on a 124 as it is on a 123, or some say even a 210.
Cost was not an object on building these, and the build quality is excellent.

Parts have been cheap,rebuilt starter $150, caliper $45, brake pads $30.
W210 rims bolt on for an updated look, and good tire options. Euro style Depot lights can be had on ebay for $150.

i drive mine like i stole it, every single day, and it always puts a smile on my face.

Crazy_Nate · #13 07-23-2009, 12:52 PM

Ok, I had a lengthy conversation with the owner about the vehicle. Let me know if anything really sticks out as a deal breaker.

The owner is actually the second owner. He bought it from the original owner's son last November.
He's selling it because he has another vehicle and doesn't need two cars. He just uses it for commuting now.
Response to known problems: slow leak at the pinion seal (?), when he bought the car the shop that checked it out said the front struts could be replaced in the future.
Cooling system: the radiator had developed a hole, and was promptly replaced. He said it's never had any trouble with operating temperature. Mainly driven on the highway in his ownership.
Oil leaks: small, slow leak at the turbo. No noticeable oil consumption.
A/C: blows ice cubes, couldn't give a definitive answer if it was still R12 (I would assume so, as he said it works surprisingly well).
Sunroof: previous owner said it didn't work. His son tried it and they had to close it manually.
Front power windows work, rear do not (shop said it was the actuator arms that needed replacing).
Power seats work flawlessly. Drivers seat has wear (expected). Says the interior is in surprisingly good condition.
No smoke in exhaust. He said there might be a little if your really stomped on it. He also said there was a little bluish smoke while starting before he had the glow plugs replaced, now, none (is that regular?).
Trap oxidizer: no clue, said he doesn't recall seeing it.
Suspension: had rear control arm and rear bushings replaced.
Major services: transmission was rebuilt by previous owner, unknown time, he says it shifts solidly but smoothly.
Any rust: says there is absolutely none. He believes that the car was garaged by the previous owner (VA car all it's life). Paint is excellent.
Service records: all from his ownership.
Recent work: new battery and alternator, tires and brakes.

If he doesn't sell it, he says he'll just keep driving it on his 30 mile commute.

Jeremy5848 · #14 07-23-2009, 01:05 PM

The sunroof can be expensive to repair but you can live without it. The rear window regulators you can learn how to replace yourself. If the trap oxidizer hasn't already been replaced, the factory recall campaign is still in effect and any dealer will do the job for you free. You might even get a new exhaust system out of it. Front shocks (struts) you can learn to do yourself. Nothing else looks worrisome. Have a shop look it over for you and then buy it.

Wodnek · #15 07-23-2009, 04:12 PM

That is a little too many items to justify a $5,000 price. Other then that, i agree with the poster above. $3500 - $4000 would be a fair price if there is zero rust and its a good runner.