As one of my 603s ate an oil squirter that came loose and used the crank as a crusher (a '91 3.5L), I suggest checking and/or loc-tite the bolts while you're in there.

__________________

Gone to the dark side

- Jeff

thats just the mouting bolts wich are all hex bolts with washers corect? not the little squirters at the bottom of the cyl?

Yep. The squirters crush pretty easily, but makes for some poor oil pressure.

__________________

Gone to the dark side

- Jeff

I kept the flexplate and torque converter that were on the 3.5.

The 3.5 balancer had the same part number as the 3.0 balancer so I used the 3.5 balancer on the 3.0 block since it looked to be in better shape. Note, I'm not saying the engines came with the same balancer part number; I'm saying the engines as I got them has seemingly identical balancers. I don't recall checking the EPC. YMMV.

Sixto
87 300D

I half expected idle issues with the 3.5 fuel system on a 3.0 block but it felt right as rain. My guess is the displacement difference is within the range of compensation of the ELR or EDS or whatever.

I don't think anything will compensate for shorter stroke. My bent rod 3.5 with no boost took off with more authority than the 3.0 in proper tune. Maybe the 55 trim turbo meant more lag in the 3.0 but it didn't feel laggy. That could be the true cost of the swap.

Sixto
87 300D

if it wasnt for the clouds of diesel smoke and the shake i would have kept driving it. what could of caused the exessive diesel smoke cloud and shake i was getting? i changed all the injectors and the crappy harness and no change. only when i ran kerosene through it did it clear up alittle.

That would have been caused by the low compression on the #1 and #6 cylinders due to the bent rods. Incomplete combustion = unburned fuel = black smoke and shaking.

thats what i thought so as always i ripped every thing apart and figured i would fix it later after learning everything i could about it. it just the little things that get me worried i am glad i found this site and all these great people.

i will be going away htis weekend but plan on switching either the blocks or the latest updated rods to my block witch are already bought...decisions ,decisions... lets go chime in..

I don't know where you're located, but I have a decent 3.5L block in SW Michigan you are welcome to, I bought it for the head.

__________________

Gone to the dark side

- Jeff

I'd check how far out of round the 3.5 cylinders are before fitting new rods. I'd Plastigage each and every crank journal and proceed only if everything is within installation spec, not just reuse spec... for both blocks. How's the cross hatch and ridge on the 3.0?

Sixto
87 300D

Why not just convert it to a 3.0L instead so you don't have to deal with another bend rod. I don't think you will loose that much of performance.

__________________
Current Garage
2008 Mercedes GL320 CDI 188k mi Repair/Work in progress
1994 S350 160k mi Garage Queen & prepping for repairs
2005 E320 CDI 203k mi Healthy & Daily Driver
1994 S350 357k mi Retried as parts car
1984 300TD 214k mi Blown OM617 Poss OM603 Swap??

Sold
1987 300SDL 200K+
1994 S320 181K mi
2008 E320 Bluetec 127k mi
1999 S420 130K mi
1980 240D 360k mi
15+ Others that has come, stay and gone

GONE, BUT NOT FORGOTTEN
1995 E320 SE 220k mi
1984 300SD 350k mi

The 350 really has a lot more torque off the line then the 300. IMHO it drives nicer. Almost no turbo lag too. Way more responsive then a 617 off the line.

Has anyone tried to buy the cylinder sleeves for the 3.5l?

-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.

honestly the 3.5lmotorlooks new both inside and out, and the people swore it was running perfect till the headgasket blew. i pulled the 3.0 out of car that had front end damage was sitting for about 6months. it was winter when i went to see it in rhode island, it started with a jump and ran great with no smoke and idled smooth. if my block is bad i will take you up on that 3.5 since i already spent 3500 bucks on bearings and rods and rings and such! ouch thats alot of money, plus the 1500 for the injectors and harness, 500 for the 3.0l and 2000 for the car, and i am sure there will be more before i am done.

just got back from maryland, hope to resume work this week.