Rebuild - Replace Motors - PeachParts Mercedes-Benz Forum

spoilsport · #1 09-18-2002, 09:40 AM

I've seen some really sweet looking 300 SDLs and 300 SDs over at EBAY with shot motors. I know that rebuilding can cost a fortune and that used motors can be found for around 2,000.

A hypothetical: If one could pick up a 1986 or 87 300SDL for a song, that had a strong body, suspension, and everything else in good working order, how much to completely rebuild considering worse case scenario ? How much to replace with a used or remanufactured motor that could be tested prior ?

Lastly, would it be better to forget that, and just buy a good used example from a reputable source....like on this Forum?!

Thanks

engatwork · #2 09-18-2002, 10:33 AM

I would pick up a W123 and rebuild the engine. Oh yea, that's right I remember, I did that last year with a '83 240D (117,xxx miles). Car cost $800 and I put about $800-900 in the rebuild. The pistons were the most expensive part at around $85/each. Did all the work myself except the actual machine shop work.
I'm not sure if the 300SDL engine can be re-sleeved or not but I know the W123 engines can be.

spoilsport · #3 09-18-2002, 10:51 AM

I do only routine maintenance like brakes, etc.

The problem with buying the beater for me is how do you know about the rest of the drivetrain if the car's motor is blown ? I guess if you pay little enough, it could always be a parts car.

P.E.Haiges · #4 09-18-2002, 11:02 AM

Spoilsport,

You can but a MB motor from fastlane for $140, but ENGINES cost a lot more (HI Larry).

If you can do most of the work yourself, you can save a lot of money by rebuilding it yourself. If you can't, a rebuilt short block with head, valves, cam and chian installed is probably your best buy. You even get a warranty.

P E H

autozen · #5 09-18-2002, 11:23 AM

My suggestion would be to look for a nice HIGH mileage business or commuter car. You'll get it for cheap. It will be in better mechanical shape than a low miles car. Probably everything will work. Since you're not a mechanic, I'd suggest skipping the beaters. When you start adding up all the time, money, and frustration it will take to fix all the things that don't work on a beater, you're better off finding a nice unit in good shape. If you like working on cars as a hobby, then that's another story.

Good luck,
Peter

Larry Delor · #6 09-19-2002, 01:50 PM

I was able to find a rebuilt engine for my 83 300D for $1600. So far it runs fine, however, I need a transmission now. (the transcooler in the radiator broke, and allowed antifreeze to get into the trans.)

Shop around for both, a nice body, and a rebuilt/used.

Btw, I have noticed, that whenever I called and asked how many miles were on an engine, or trans., they always said around 130k miles....hmmmm

gsxr · #7 09-19-2002, 03:30 PM

I think first you should figure out what the sellers mean by "shot motor". Could just be a bad head gasket. Next, there is a big difference between a 300SD and 300SDL. The former uses an OM617 engine, the latter has an OM603. You can buy a good used 617 for probably under a grand. 603's tend to be 2-3 thousand used, unless you find a steal like the one on eBay this week for $1000 (no compression test though, and not in the car.)

Brand new (ok, MB factory rebuilts) 617's are something like $4k with all accessories, and new 603's are about $12k. MB does not offer a rebuilt 603. You can buy a rebuilt 603 frm Metric Motors for about $8k plus core and shipping.

Bottom line: Unless you have a source for a GOOD, cheap, 603 you could be taking on a very expensive project. If you are looking at an older SD with a 617 those are cheap & easy to find.

spoilsport · #8 09-19-2002, 07:13 PM

Thanks very much for all the replies! I think I'll steer clear of
the SDL's and their more expensive parts. I have heard in genereal that parts for W123's and W126's are quite reasonable.

autozen · #9 09-19-2002, 11:20 PM

Larry,

Before you condemn the trans cooler, check to be sure the rubber vent on top of the transmission wasn't knocked off during the engine job. If this little vent is missing it is possible for water to enter the top of the trans.

Spoilsport,

The 126 chassis came with both the OM617 and the OM603. They started using the 6 cyl motor in the SEL body late 1986.

Peter

Larry Delor · #10 09-20-2002, 01:12 PM

Peter,

Thanks for the idea, but the car had not been driven in the rain at all, the day that it happened.
Actually, I am assuming it happened that day, since everything was normal, prior to the engine transplant ( which was done over a very leisurely lenght of time ).
Besides, I have already yreplaced the radiator, and the two rubber lines going to it, and the pan gasket. After taking it out for a test-drive, I noticed leakage again. It thought that it only leaked when its hot, but, after sitting for over a week, I see it has slowly bled itself to death. This, of course, makes me wonder what the hell else could be wrong with the thing.
( sometimes when I walk past it, I cuss at it in German )

-Larry

autozen · #11 09-20-2002, 08:37 PM

Did you wash the car?

Peter

spoilsport · #12 09-21-2002, 12:07 PM

Quote:

Originally posted by gsxr

Brand new (ok, MB factory rebuilts) 617's are something like $4k with all accessories,,,,

So how long would one expect an MB rebuilt 617 to last for their $4,000 ? If it's anywhere near what I expect, it still sounds like an outstanding deal, providing the cost of having a good shop install it is not too prohibitive.

gsxr · #13 09-21-2002, 12:18 PM

A new or rebuilt OM617 should last 400-500kmi if cared for properly. There are many on the road today with 300k+. Usually the car doesn't last that long (accident, rust, etc). Which is partly why there are plenty of good used 617's available.

Any 617 that fails sooner is probably due to neglect or poor maintenance. They're pretty close to indestructible.

spoilsport · #14 09-21-2002, 12:33 PM

Quote:

Originally posted by gsxr
A new or rebuilt OM617 should last 400-500kmi if cared for properly. There are many on the road today with 300k+. Usually the car doesn't last that long (accident, rust, etc). Which is partly why there are plenty of good used 617's available. Any 617 that fails sooner is probably due to neglect or poor maintenance. They're pretty close to indestructible.

As the owner of 2 VW TDIs, this is what I thought. So now, it seems like a good strategy is to find a good rust-free example, with a clean interior and a clean history of accidents. Then, if you live in the Houston area like I do, where there is never salt on the road, one could hope for a very long and reasonably affordable relationship!