Lets Talk W140 S350 - PeachParts Mercedes-Benz Forum

DieselPaul · #1 09-29-2010, 12:57 PM

Has anyone on here had one? I'm looking a beautiful 1995 with not a ton of miles on it. The motor smokes like all hell and the owner has been told the motor is bad. He told me its some oil/turbo thing that burnt the motor up. I have a sneaking suspicion it is the classic 3.5L rod issue. So heres the deal, I want to buy it and put my 181k 1987 OM603 in it, if my motor compression tests good. I would like to drive the car for a little while but ultimately I'd like to sell it next year.

What are these things worth? Kelly bluebook is like $5,700 with the miles on the car. Retail KBB is like $8k.

However mine will have a funny story, 160k mile car, 180k mile smaller motor. To anyone who knows their diesels well, a 3.0L is the way to have the S350, but I have a feeling I'll have trouble selling it. So it would have to get sold a diesel nut like myself, who doesn't like to pay KBB. The car is black/black, nice leather, no rust, 8 hole alloy wheels. Is it worth, I dunno $4k? That's what I think I'd have in it done. I'd like to enjoy it for a little while then be able to get out of it, maybe make a couple hundred bucks to cover my labor.

Also, how straightforward is the 3.5 -> 3.0 swap if you have both complete cars?

tbomachines · #2 09-29-2010, 01:05 PM

As far as ROI is concerned, I'd imagine a rodbender w140 is not the best way to go. If you want a huge, classy, nice riding car go for it but I wouldn't expect to make a profit on it.

babymog · #3 09-29-2010, 01:14 PM

The early ones have a reputation for being fairly reliable, but rumor has it that the later production 140s started to dip in quality, and things like the door-pull pump or HVAC displays will break you.

That said, diesel 140s are pretty uncommon, so hard to put a value on it. Even the S320 with another ~90hp was a slug around town IMO, pretty heavy for the power, but nice highway cars when all is working.

I would consider such a project, for around $2000.

As far as the engine swap, not sure what fits and what doesn't but since you have both engines complete, should be fairly straightforward. You'll want the 140's turbo and exhaust manifold if in good condition as well as intake plumbing, mounts, don't know what else to interface with the transmission.

Hit Man X · #4 09-29-2010, 01:14 PM

Sixto ran one for a while, I think with a short block he picked up off of me.

Jeremy5848 · #5 09-29-2010, 01:32 PM

If you can get the 140 for next to nothing, already have a good 603, and can do most/all of the work yourself, you might make a few bucks when you sell. The challenge is that by creating a "hybrid" (that's the polite word

) you will scare off all but the most sophisticated buyers (meaning us forum members

).

Looking at the car as a keeper/driver, it would be a nice one, so long as you have an inexpensive source for the parts mentioned by Jeff, as and when they break. The only "reasonably inexpensive" Mercedes is one for which you have a "source" for inexpensive parts and do all your own work.

Sixto was happy with his 140, I believe, but it was involved in an accident and went to Mercedes heaven.

He salvaged the #20 head, which I now own. Someday it will go on the 603 in my '87 300D Turbo.

Jeremy

compu_85 · #6 09-29-2010, 01:49 PM

I also thing this engine has bent rod symptoms. Just realize that a W140 is not for the faint of wallet and you'll be ok.

-J

sixto · #7 09-29-2010, 02:21 PM

According to carfax, my 93 SD is registered in SoCal, salvage title and all.

All you need from the donor is the short block and IP. Everything else will be on the 3.5 and likely in good shape, including - head, manifolds, turbo (might as well use the 55 trim), oil pan, oil filter housing, etc. You can even keep the donor long block intact if you're confident in the head. Then you can offset costs by selling the 3.5 head. There's some demand for the 3.5 cranks as well. I heard it's the key to stroking an M104 to 3.6 liters. It's all nuts and bolts, no fabricating.

What you should pay for the S350 depends on the condition of everything else like transmission, ACC, interior, amenity features, etc. Being a 95, it's subject to disintegrating engine wiring harness but even a catastrophic wiring harness failure shouldn't strand you. www.v12uberalles.com is a good resource to keep 140 doodads humming.

I don't think the swap will affect residual value in a big way. Anyone who knows will be happy to have a 3.0 block. Throw in the 3.5 block for those who care. Note that decent gasser 140s can be had for less than $4000 and some for less than $3000. That'll probably have more effect on the future value of an S350 than engine displacement.

If time and labor mean nothing to you, throw in a head gasket and see how much that cuts down exhaust smoke. Lucas oil additive did a fair job reducing smoke on my 93 SD while I was waiting for Hit Man's block to arrive.

Sixto
87 300D

jonbobshinigin · #8 09-29-2010, 03:17 PM

Yeh...I have a similar situation:

Dad bought a 1993 S350 140 Body with typical signs of Rodbender. Recently I found a 1987 300D with a good engine but rusted body for cheap. In the big picture, I can swap the engines. Sell parts from the 3.5 and recoup quite a bit. The #17 will more than cover the cost of my entire parts car, but I will most likely keep it for MY wagon with the #14 head.

I will say however, the W140 body is complex. Intimidating for me at least. Even with a good running engine, unless everything else was perfect, I would be weary. The luxury items will nickel and dime one to death...

4thesporty · #9 09-29-2010, 05:33 PM

My dad has the (w140) 300SD. He got it cheap (burning 1 qt/100 miles

) But everything else is perfect on it. Plus it's the right color combination (dark blue/dark tan).

He bought a metric motors engine for it and I have to say it is one of the nicest cars I have driven. He's not much of a wrencher anymore and he can foot the bill on it with the indy.

All the cool little gadgets on it would be a nightmare if something went out, also heard the ACC will leave you sleepless at night.

When you open the trunk a little handle pops out for you to lift it with, that's luxury!

DieselPaul · #10 09-29-2010, 11:49 PM

I'm thinking I'm going to pass. He wants $2k, I'm thinking $1700 will buy it. I have a motor but it will need gaskets, DV seals, filters, fluids, etc to get it back up to snuff. The car also needs tires. The swap will cause the A/C system to be opened, the A/C system is one of my bigger fears on the W140. I estimate I'd probably have $3k in the S350 being conservative on parts and tire costs. But if my motor needs major work, the trans is bad, the A/C needs work, etc I could easily dump another grand or two into a $4k car. There is no room to enjoy and make some money to cover my labor from the swap. A ton of work and breaking even or losing money isn't my idea of fun. And (flamesuit on) in terms of a driver my '87 300D is a better car. I appreciate the opinions guys!

sixto · #11 09-29-2010, 11:52 PM

Why do you have to open the AC? Leave the compressor in the S350. It will bolt to the .96 block.

Sixto
87 300D

DieselPaul · #12 09-30-2010, 12:10 AM

The cars been sitting for like 6 months. I guess I could get the motor out without pulling the a/c.

sixto · #13 09-30-2010, 12:31 AM

I have faith in you

Sixto
87 300D

compress ignite · #14 09-30-2010, 01:32 AM

And then offer him $1,000 for the entire car.

(He's still making out like a bandit on the trail,no one but one of us would touch
that chassis!)

babymog · #15 09-30-2010, 01:11 PM

Let me know if you don't buy it, I might be interested as I too have a spare 603 sitting around.

Another angle is parting the car, the head is worth most of the $1500, crank probably another $250-$350, vac-pump, alternator, front cover, belt tensioner, IP, turbo, exhaust manifold, ... you could throw the rest away and it's already worth your time. It'd be a shame and I'd rather see it get a fresh engine, but it'd be hard to lose if you buy it and change your mind.