Wanting to buy '93 300d have quick question - PeachParts Mercedes-Benz Forum

jobadiah · #1 12-21-2017, 06:45 AM

Hey wanting to get back into a diesel and saw one advertised a few hundred miles from me, supposedly in good shape except he says the shift points need adjusting, that it wants to rev high before it shifts. Any best guess on causes from anyone, could it be vacuum related or looking at a new tranny? thanks

Mxfrank · #2 12-21-2017, 07:46 AM

Generally if there's a vacuum leak, it shifts hard but doesn't flare. The only way the vacuum system could be at fault is if some shade tree went in there and "adjusted" it. Which would make you wonder what else was "adjusted". So what could cause a flare?

1) Low fluid level (why?). If this has been going on for a while, low fluid will cause irreparable damage.

2) If the flare is between 2-3 or 3-4, a K1 or K2 piston or spring could be the problem. Not too hard to fix.

3) If the flare is between 2-3 or 3-4, a failing clutch pack could be the problem. Requires a rebuild.

So my advice is that if the owner says the problem is a simple adjustment, make the sale contingent on him making the adjustment.

jake12tech · #3 12-21-2017, 08:07 AM

Most 300Ds aren't worth more than $1000 anymore despite their condition because it's a real hobby car. If you can get it for that price, I would check the trans fluid and sew if it's low or smells burnt. Worst comes to worst you have to put a trans in it or rebuild it. Neither which are not difficult.

jobadiah · #4 12-21-2017, 11:02 AM

Thanks for the responses, sounds like more than I want to get into considering the distance and not being sure how big a deal it is.

vstech · #5 12-21-2017, 11:19 AM

It is a great platform good cars usually.

The Bowden cable is on a fragile plastic adjuster... easily damaged when old and brittle.

Also the throttle linkage is all plastic and wears out... easy to replace.

vstech · #6 12-21-2017, 11:20 AM

If the miles are high pull the valve cover and look at the cam gear teeth... 93 had soft gears that wore and took out the chain.

Bengoshi2000 · #7 12-21-2017, 12:29 PM

Until you drive it and do some in person diagnosing, "wants to rev high before it shifts" could mean anything... could be as easy as a shift linkage adjustment or as bad as a transmission replacement.

Can't say I agree with the statement that "300Ds aren't worth more than $1000 anymore despite their condition because it's a real hobby car." That's simply not true for w124s (as the OP was inquiring about... nor w123s for that matter). These ain't Triumphs or MGs...

jake12tech · #8 12-21-2017, 12:45 PM

Quote:

Originally Posted by Bengoshi2000

Can't say I agree with the statement that "300Ds aren't worth more than $1000 anymore despite their condition because it's a real hobby car." That's simply not true for w124s (as the OP was inquiring about... nor w123s for that matter). These ain't Triumphs or MGs...

Sad to say but that is the vibe I get anymore. I get a lot of questions like "why do you bother putting money into these outdated dinosaurs" and people offering me $1000. Most cars that I see online that are nice sell for about $1k and on a great day $1500. Or people saying it's such a nightmare to work on, overengineered etc. It seems like a small crowd who likes or is interested in these cars. A majority would rather drive a beat up old F150 or a piece of crap Honda/Toyota or new car with a warranty that they can terrible parts from AutoZone.

I'll keep running my Benz diesels, but it's few and far between who actually know its a good car.

oldsinner111 · #9 12-21-2017, 12:45 PM

just shift it manually,I did my sd that way.Got rid of the vacuum junk.

BillGrissom · #10 12-21-2017, 03:05 PM

If like my earlier 1984 & 85 300D, if the Bowden cable adjustment is too loose it will shift high. That happens when the plastic adjuster cracks and falls apart. Wonder why such high-end masterpieces couldn't have used metal adjusters. I don't think the plastic could be easily replaced. I just cut & slotted 1/4" fuel tubing to set the position and has worked fine for years. Main thing is to drive it and judge if just "shifting high" or if it is flaring between gears. As mentioned, that could be worn clutch plates (my 96 Plymouth van, since fixed) or sometimes an easier fix in these M-B trannys (post 2).

I think Jake is realistic on pricing. If parts weren't so expensive and/or unobtanium, these cars would be more valuable. Re "crappy Jap cars", read the book "Into the Wild" and see how the Park Rangers found the kid's old Datsun, which his dad had berated, and drove it long after dad's Cadillac was junk. Anyway, you M-B guys are mostly tolerable, at least compared to Tesla fanboys.

tdoublenastywitit · #11 12-22-2017, 12:48 AM

Anyone who is actively in the buying an selling market at the moment knows a w124 is worth $1000. Unless it's a sport line 500e or pre 100k