603.96 swap for 603.97 question
 

I was told the only thing I need to do to swap a 3L for a 3.5L is change the motor mounts. Is this correct?

In what car?

a 3L six from a 1987 300 sdl into a 91 350 sdl

Been there, done that. Iirc you will need to use oil pan from
350sdl too. Don't remember reason though.

The 3.5L engine's oil pan doesn't have the little side access cover.

Be sure to nab the AC compressor, bracket, and alternator off of the 3.5 as they are different. You could also move over the 3.5's water pump pulley as it's smaller (to spin the fan faster).

-J

Ditto on Compu85. Done this exact swap many times. The oil pan from the 87 with the side sump cover fits fine on the 91. If the AC system is sealed and working on the 91, just tie the compressor aside, and move the bracket over and leave the system sealed. One is a 10P15C, and one is a 10P17C, dont recall which is which. You can tie the PS aside as well and leave it sealed.

And I used the same mounts as well with no issues.

The 350 has the larger 10P17C compressor (and a parallel flow condenser!).

-J

Hmm, I didn't realize they used a PF condenser. Maybe that's where my blockage is, haha.

Thanks much for all the input. I will be interested to see the difference in the two engines. I own a 90 350 SDL with 265k on it and running strong. This 91 was an unintended purchase. I saw it a a used car dealer and stopped to see what it was. Interior was even better than mine but needs paint job. 17"AMG wheels with good Michelin tires. I stuck my finger in the water reservoir and came up with a finger full of oil. Ended up paying $1500 for it as a parts car. My only quandary is what to do with two of these.

It's a slippery slope... One day you wake up, and you have 19 MB diesels... I'm STILL selling off cars. It's great fun buying them, not so fun selling them. But, I will say, you have the perfectly outfitted shop to do that type of work. First class! I'd love to turn a wrench or two in there.

Going in for a total hip replacement 8/5 which will slow me down for a while. If your ever in this area again give me a call Al

Oil in the cooling system is not the end of the world. Since this is a project car, replace the head gasket and see if oil consumption and exhaust smoke is tolerable. Mabye it can remain a 3.5.

Are there markings to suggest the block has been replaced such as a head casting later than -17-? Note the tag on the passenger side bell housing flange for a dealer replacement .970 -

http://www.w124performance.com/image...e/603.970d.jpg

Sixto
87 300D

Hi all,

Just finished a swap from an OM603.97 ( rod bender) back to a OM603.96. Only replaced the block. Head, IP, is from the original .97. Hving timing issues. Can I use the pump from the original car or I need to find an old Injection pump as well ? Any help would be greatly appreciated.

Thank you all !

Mine had oil in the coolant. Probably the best hg failure you can have, fwiw.