I have desided to look for an engine replacment/swap for my underpowered merc 410 1990 hymer motor home, OM602.942 2.9 turbo, I have spent many hours trying to improve performance, see previous posts, but decided i'm flogging a dead horse and need to get something better in there.


I'm doing quite well having found the newer version OM602.982 engine from the E290 TD Merc saloons, up to 1999, but not released in the UK. Apparently from various forume's, its a great engine, lots of power, but still very reliable with high millage history.
The stats are:
The old engine OM602.942, 92BHP and 192 max torque
The newer 1997 OM602.982, 129 BHP and 300 max torque.

The HP increase isn’t much changed, but it’s the huge increase in torque that's interesting me.


The beauty about this engine, is that physical engine block, size, mountings, head casting, etc. seem exactly the same, so should drop straight in and mate up with my existing gearbox etc. and it has direct injection, VNT turbo, and re-designed head, as well as VE-injection pump.

My question is how much of the extra power/torque has come from the newer Bosch VE-style rotary distributor injection pump, which is electronically controlled with the ECU. And how much from the direct injection, redesigned head and VNT turbo? My very simplistic way of thinking is that the diesel pump is only delivering fuel, so as long as there is enough, it won’t impact performance? I see the main reason for the electronic pump, is fuel economy?


Adding an ECU system to a none electronic different vehicle, is making me shake with fear, as I’ve been down that road before!
So my questions are,
a) If I use my existing mechanical pump, I think it should fit, although not 100% sure, how much of the gained torque/HP would I loose, if any?
b) Am I right to be petrified of trying to retro fit the engine ECU system, as if possible will make the straight swop easier, give better economy and give me the option of re-chipping the ECU for even better performance?

I am presuming, over and above the engine electronics, the ECU option is going to require electronic speed input, throttle peddle position and even gear section, plus more? If all this is the case, it’s starting to become un-viable. to try and use the ECU route.

What do you think? Any knowledge/advice much appreciated.

I would not consider trying to retrofit an ECU into a non ECU power train. The electronic controlled injector pump has injection timing adjustment built in so you dont have a timing device in the drive of the injector pump.
There are many other inputs to the ECU. My jeep has an ECU that has 92 wires. It is drive by wire.
You can probably get much more out of your existing motor by doing work on the IP, fitting an intercooler & changing out the turbo.

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

so... they made a DI version of the OM602? I'm guessing this is not a mercedes engine? got pics?
I'd LOVE for this to be a Mercedes 5cyl identical to the OM602 that is in the 124/201 MB's...

__________________
John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 560SL convertible
1987 190D 2.5-5SPEED!!!

1987 300TD
2005 Dodge Sprinter 2500 158"WB
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!

Sounds like a Korean version. A bit like a 606 rod bender.
They made 5 cylinder versions of rod benders. I was going to put one in my 124 but it was not that simple.

__________________
Grumpy Old Diesel Owners Club group

I no longer question authority, I annoy authority. More effect, less effort....

1967 230-6 auto parts car. rust bucket.
1980 300D now parts car 800k miles
1984 300D 500k miles
1987 250td 160k miles English import
2001 jeep turbo diesel 130k miles
1998 jeep tdi ~ followed me home. Needs a turbo.
1968 Ford F750 truck. 6-354 diesel conversion.
Other toys ~J.D.,Cat & GM ~ mainly earth moving

In a very general sense the power is in the IP. If you put the .942 IP in the .982, prepare for 92BHP. Beyond that, you're not going to feed DI injectors with an IDI pump.

92BHP seems wimpy from a 602 turbo but maybe that's a difference in rating system. The US spec 602.962 manages closer to 120 HP from 2.5 liters.

If money isn't an issue, consider having the .942 IP tweaked with 7mm elements by MYNA in Finland then hang on.

Sixto
87 300D

Yes its a merc engine i believe.