Mercedes W114 250 Coupe - help!

Page may contain affiliate links. Please see terms for details.
MOT just passed. I thought the odometer wasn't working but it's actually moved on by 6 miles in a year and a half, about 244 less than I estimate I did. Great car for a dealer!

Cold start up was a royal PITA, I suspect the fuel needs changing but the cold start up and idle map has still to be adjusted. I'll give the plugs a clean as it was misfiring a bit but on the run to warm her up after the MOT everything suddenly clicked and off she shot.
 
Well done Charles it passed the MOT,you took a big chance with a dodgy start up and then taking it to the test centre,but you have done a awful lot of work on that car so I suppose it was no surprise it passed,I wonder how many W114's they get on their ramps.
 
She just needed an Italian service, and no chance at all as there is no emissions test apart from visible smoke on cars this old. Plus, they know me well as I am only 400 yards away, so if I broke down they'd give me a push!
 
Plugs cleaned, yes they were coked, so overfuelling when cold (still to be sorted). To do the remaining stuff requires me to get on the drive for better access and light. This liquid stuff falling is vexing me somewhat!
 
Wonder if your fuel rail supply pressure is a mite too high Charles or is it a mapping thing?
 
Mapping thing Graeme - it's over-fuelling on start up and the timing is out when cold. That's a difficult mapping session to do as it requires the car to be cold.
 
Will it be with you at BOTG Charles ?
 
Is this still running d-jet or did you go megasquirt (I have not read all 136 pages). IF D-jet, temp sensors play a big role in how the mixture adjustment works.
I was under the impression that the MOT was a thing of the past for these older cars.
 
No, full megasquirt.

MOTs no longer a requirement for cars over 40, but I think that's bonkers and I'll always get one!
 
Clean plugs always make for much easier starting, as does the clearing all the moisture built up over the winter. It's the fuelling immediately post start up that needs adjusting, but that can wait.
 
Cleaned, polished, oiled, watered, fuelled, bits of internal trim fitted, still a few things to do but nothing major. Just need to find my power pack as the lighter socket is u/s, and check the levels in the morning. Can't find the touch up paint, so a few tiny chips in the engine bay will remain unsorted. Number of breakdown recovery people to be found, but I'm as ready as I'll ever be.
 
Alternator belt snapped on the way to Goodwood on Sunday, which given how new it is and the second time, indicates an issue with belt and pulley alignment. One of those things that happens with pulleys, alternators etc coming from different cars, the nature of such things. It was a pleasant day to break down, obviously the car was easily driveable to a safe place to wait on the A3 and I was back home within 2 hours.

Apart from that, the fan thermostatic control will will be fitted tomorrow. It's also leaking a tiny bit of coolant, which I think is as the result of a poorly sealing radiator cap so checking that out too.
 
An interesting thought Graeme, I shall study the link with interest.
 
We found the alternator fan and belt end was wobbling a little, took out a washer there that was not original, and it is now steady. I think the alignment is not perfect but that's a hunch, we have left the belt just a tiny bit less taut than it might.

Engine fan is now wired into a proper thermostat, so result is the car is now running at the correct engine temperature.

Compression tests all fine.

Next job, get the starting map sorted.

w114fan (1 of 1).jpg w114engine temperature (1 of 1).jpg
 
Any pictures of the old girl in action this summer Charles...?
 
Engine fan is now wired into a proper thermostat, so result is the car is now running at the correct engine temperature.

w114engine-temperature-1-of-1-jpg.76995

That to me looks like it's running a bit hot
 
As the owner of a CX I have always craved an SM . BuT your W114 is truly stunning. I need to set a day aside to go through the entire thread though !!
I am told you sourced 15’’ steels & trims . I am after some steels for my R107 - any advise please - though I believe 14’’ are easier to come by
 

Users who are viewing this thread

Back
Top Bottom