Improving Mercedes OM603 engine efficiency

[320touring]

Last night, I had this out on an epic adventure - covering about 120miles in deepest, darkest central belt.

Observations:
It's nearly as quick with your foot just resting, but not engaging kickdown as it is where you are 'Double kickdown BANZAI"

A B road blaster it is not, although it grips bloody well, and once speed is achieved, it can be maintained!

The headlight aim could do with some work.

Front lower arms are needed - is it a garage job?

The gearbox is a bit doddery - a fluid and filter change would be beneficial.

Lastly, and most importantly,

I do enjoy driving it - it's so comfortable, and once you work out how the engine likes to be used, it'll happily keep up with traffic. I got out at the end and felt like I'd just driven to the local supermarket.

[meloccom]

I have found this YouTube channel “MercedesSource” has a lot of useful information about older Mercedes Diesel vehicles. Would send you a link but not allowed.

[dreamsinger]

Originally Posted by cRiPpLe_rOoStEr

There is no cheap when it comes to Mercedes-Benz...

Not initially but with the diesels a maintained one will be cheaper if you drive it forever and take care of it.

[320touring]

Originally Posted by meloccom

I have found this YouTube channel “MercedesSource” has a lot of useful information about older Mercedes Diesel vehicles. Would send you a link but not allowed.

Thanks, already watched a fair few of his videos - helpful if a bit long winded..

[320touring]

Tonight I entered to collect a bulk load of fuel.

Jim had made an excellent start by setting up the pump, then forgetting it would siphon..

Oh how we laughed




Next up was to start pulling the containers out the back of the car and get filling.



The pump was heavily aerating the veg ( you can see it on the 20L tubs on the LHS of the above picture), so we watched it settle as we continued to fill.

It rapidly cleared to a lovely looking liquid, so we just boshed 20L in the tank

In fairly short order 230L was pumped. 210 in containers and 20L in the tank. We'll likely filter the 210L unless the Merc ain't grumbly on what's in it

[DieselJan]

Being a heavy car with a tired autobox and low power, it feels like you are always accelerating - something I need to try and avoid.

With it being mechanical pump, I don't even get DFCO
.................................................. ...................................

I have a surprise for you. Machanical pumps has DFCO feature build in. If you decelerate or go downhill the pump turns faster than what your foot demands. So no diesel is pumped to injectors.
Test procedure: Drive downhill on straight slope in gear, take foot off diesel pedal, listen to engine, switch off engine (Don't remove key!! or engage steering lock!!), listen to engine, switch on engine.
You will hear no difference, which means it has DFCO.
Enjoy

[squirrl22]

Couple things you can do, that I did with my 1.6 Jetta diesel: 1. wrap a nicrome wire around each injector, attach to your battery via a relay keyed to your ignition. Ignition on, the wires almost instantly warm up to 200 F(depending on wire type, length, thickness) which then warms your incoming fuel.
2. modify your rev limiter, so that it doesn't start cutting off your fuel @3000rpm, and lets you get full fueling all the way to your rev limit before cutting off the fuel.
Both create a big improvement in driveability, and preheating the oil will save you a LOT of engine damage (coking of injectors& combustion chamber, lubricating oil turning int sludge, etc)

[cRiPpLe_rOoStEr]

Well, nowadays some spark-ignited flexfuel cars rely on a similar system to pre-heat ethanol as a cold starting aid, but I don't know about any Diesel featuring it as a factory-fit.

[squirrl22]

Originally Posted by cRiPpLe_rOoStEr

Well, nowadays some spark-ignited flexfuel cars rely on a similar system to pre-heat ethanol as a cold starting aid, but I don't know about any Diesel featuring it as a factory-fit.

Are you saying there are flex fuel diesels? I've never heard of one, so why would an OEM bother with nicrome wires as a factory fit?

[ratgreen]

I hope you've changed any o rings on the fuel pipes, if your engine has them that is. I'm not familiar with om603.