best years?
 

Hi, I have jumped ship from w126 gas models. I am in search of a nice diesel to buy to tinker w/ wvo. Is the 5 cylinders more durable than the 6s? How about the 4 cylinder models? Certain years better than others?
Anyone selling in NJ area. I think I want to start w/ 123s but open to all models.


How about the bmw 524tds?


Thanks,
Don

The iron head engines (4 cyl and 5 cyl) are believed to be more forgiving than aluminum head engines (4, 5 and 6 cyl). You won't go wrong with any of them. The risk is buying someone else's problem which is more likely to happen with a 6 cyl aluminum head engine. There are rewards to offset the risk.

Start by deciding what body you want (W115, W116, W123, W126, W201, W124) then live with what engine comes in it. Here's a guide - http://home.hiwaay.net/~gbf/mbmodels.html

524tds don't get much respect around here. Folks seem to have a problem with timing belts. If you like to shift a turbodiesel engine and fabric upholstery you have to roll your own MB or get a 525td.

I like the 96-97 Passat TDI but not enough to live with shifting.

Sixto
95 S420
87 300SDL

alloy heads are fine
 

I bought a 6 cyl alloy multivalve headed W124 OM606 with 50k miles and it now has 175k without a murmur of a problem. I think regular servicing is all they need to avoid problems.

The only two engines that you want to be cautious about are the OM603 in the 87 300D and the one in the W140 chassis (92-95 300SD/S350D). The former has a weak aluminum head and the latter has weak connecting rods. The OM606 engine, the last of the indirect injection aluminum head engines found in the 95-99 E-class, seems to be the best of its kind when it comes to smoothness, power, economy and overall durability. The "other" kind (iron heads, pre-86) are also very durable, but lack in the other categories, though they have their own appeals, like simplicity and character.

This here has some decent info too - http://www.peachparts.com/shopforum/diesel-discussion/130871-one-better-help.html

Thanks folks.
Back to the hunt!

Well the 3.5L 603 was used in W126's as well. Any S class diesel from 1990 on has this engine in this country.

Also a 603 in a W124 with a 14 head will crack just the same as if it was in a W126.

Define "best" I would rate the 350SD as my personal favorite W126 diesel. With the 300SDL in a very close second.

As for "best" diesel it is hard to fault a turbo charged 606. Nothing like being able to drive a diesel car with some power.

TRAITOR!!!!!!!
;)

You are absolutely correct. I had a feeling I was leaving something out. I think I need to get more sleep!

What better year than 1987! Two of the fastest production diesels made up to the mid 90's. 190D 2.5T and 300D 3.0T. The heads were an issue, but they will last forever if you care for it and don't overheat it.

I should clarify....not best but most durable. I am going to experiment w/ wvo and I think I need a forgiving motor as all I have read on the suject deals with works/doesn't work. I don't know if any studies were done on fuel ratio, lean/rich, the lubricating properties of wvo, the byproducts of the burn that will mix w/ the motor oil...etc.

NJ Area
 

Where in NJ are you wanting to find some? I'm in Hunterdon County (west centralish area - Clinton, NJ or Phillipsburg, NJ) there are a couple i have seen on the road this week and some other ads for around this area..

lmk

Then get a 617. If you blow it up you can pick a used one up for cheap. They made tons of them so parts are cheaper as well, 603's in comparison are rare. If you blow a 603 up you can't run down to the junk yard and get a nice running one for $100.

Take a good look at the 616, which is the 4 cylinder normally aspirated iron block/head engine of the 240D.

- Patrick

the 616
 

in the 240 is widely acknowledged as one of the highest quality simplist and most durable engines ever built. there are examples of well maintained examples still running around with 500k miles on them. if you change the oil every 3000 and use really good oil like rotella 15w40 or similar you just about cant wear them out.

tom w