[300ceswap]

Sorry if repost i could not find anything exactly like this.

So i have a 96 e320 with a blown block then i have a 89 300ce that is totaled but the engine seems to be perfectly fine.

Well i need a car that RUNS so my question is how hard would it be to swap the 3.0 M103 into the e320 which came with a 3.2 M104 i believe. I see that there are some differences like the liters but they are both straights 6's on a w124 chassis. I don't know much about cars and how they work but my father does and he would be helping me do this if it is possible.

Thanks in advance and sorry in advance if repost >.<

 

[TexFinn]

You have a 96 W124? Interesting...

Anyway... The two are quite different motors, different fuel system, different engine management etc. etc. With enough money, knowledge and time many things are possible, but whether it's worth it is another question.

It's not like used M104s are rare as hen's teeth, or something, so my suggestion would be to forget about the swap and get yourself another M104 and be done with it.

 

[LeftCoastGeek]

yeah, you'd need to swap the whole nine yards, the M103 wiring harness, all the control stuff behind the battery, the stuff on the left fender like the EZK, etc etc etc. and you'd need to interface this to the dashboard harnesses. Pretty sure the CIS and HFM-SFI systems use different fuel pumps, as CIS uses higher fuel pressure.

I think anyone who does this swap had better well have a very thorough understanding of both systems and their control electronics, and the rest of the two generations of cars. The M103 CIS motor doesn't have a ECU running the whole nine yards, it has analog and frequency/duty cycle test points, instead of the the ODB-I diagnostic codes of the HFM-SFI system.

if you're an American, your 1996 is almost certainly a W210 chassis, newer than the W124 of the 300CE donor. while the cars have a fair bit in common, they also have a bunch of differences. the 96+ USA engines have ODB-II, the M103 certainly doesn't. This would never pass a smog test in California, you can only put same or newer year engine in a car here, and it then has to pass the smog rules for the year of the newer engine, and a state smog referee has to inspect and approve it. I wouldn't be surprised if details like engine mounts have changed a bit on the w210.

does a 1996 W210 have hte 5-speed electronic transmission? it's controller might not be happy without the M104 ECU

 

[oefvetw124lover]

How about another Course of Action (COA)
Engine 1997 Mercedes Benz E320 with 71 079 Miles 3 2L Motor | eBay