Still muddling around trying to figure out what to do. Will a 603.971 engine from a 93-95 interchange with a 603.970 from a 90-91 SDL?

The long block and IP will interchange. The oil filter housing have different attachment locations for the oil filter cooling hoses. The .971 has a vacuum wastegate actuator (boo!) vs the .970's pressure actuator. The exhaust manifold and turbo exhaust housing orientation are different since the .971 has no provision for a trap oxidizer (even if the .970 didn't come with a trap oxidizer). That might mean the downpipe of one won't align with the turbo of the other. The engine oil dipstick of the .971 comes up by the IP but that shouldn't matter in either application. Some .971s have a trigger wheel on the crank pulley which can be transferrer to earlier 603s. That's as much as I remember right now.

Sixto
87 300D

Ok, I assume since I have an old .970 I can change out what i need to to make this work. I know most you guys don't like this engine but I put 270K on the old one and like the feel of it. Changed out the timing chain and head gasket at 150K and use Duralube. The car only goes on long trips and I have heard the engine has more problems if used on short hauls. Being retired having the old block sleeved and getting upgraded pistons and connecting rods is, I think, a bit pricey for me. At my age the car may last longer than I do anyway.

Your better off with a 603.96 in there.

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

The .971 has the same HP as the .96x, with more torque. What's so bad about that?

-J

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

A bit of insight. I'm doing a flavor of that swap, but more opposite (W126 powerplant into a W140). Here is what I've seen as different thus far.

Last minute tips? 1994 S350, repowering with a 3.0L OM603

__________________
1987 300SDL #1, 1987 300SDL #2, 1980 240D, 1982 300SD, 1994 S350, 1990 350SDL, 1991 350SD, 1985 300D, 2005 E320CDI

Gone, but not forgotten: 1981 300SD, 1982 300SD, 1987 300SDL, 1983 300TD, 1980 300CD, 1981 300SD #2, 1987 300D, 1987 300TDT, 1980 300D

The turbo is different for certain. In fact, if you use all your W126 exhaust manifold/turbo pieces, I would be VERY interested in the W140 turbo if it's in really good shape. Mine is passing oil through the crossover.

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1987 300SDL #1, 1987 300SDL #2, 1980 240D, 1982 300SD, 1994 S350, 1990 350SDL, 1991 350SD, 1985 300D, 2005 E320CDI

Gone, but not forgotten: 1981 300SD, 1982 300SD, 1987 300SDL, 1983 300TD, 1980 300CD, 1981 300SD #2, 1987 300D, 1987 300TDT, 1980 300D

Oval pistons

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

IIRC the .970 and .971 use a 55 trim T3 vs the .96's 50 trim. If the .971 turbo is in better shape, swap the compressor and turbine housings as necessary. You'll have to clock things by trial-and-error.

Why are you replacing the .970? It might just need a head gasket.

Sixto
87 300D

If you have a reman engine is that even an issue?

I haven't seen a first hand account of a reman engine going bad, just rumors.

-J

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.

I've seen the rumors as well. I passed on a reman for $700.

__________________
http://superturbodiesel.com/images/sig.04.10.jpg
1995 E420 Schwarz
1995 E300 Weiss
#1987 300D Sturmmachine
#1991 300D Nearly Perfect
#1994 E320 Cabriolet
#1995 E320 Touring
#1985 300D Sedan
OBK #42

Well I'll keep running mine. 70,000 miles so far!


Sent from my iPhone using Tapatalk

__________________
1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.