W124 300CE-24

Author
Discussion

BarcelonaLewis

Original Poster:

150 posts

135 months

Thursday 22nd August 2019
quotequote all
Hello all,

I bought a 1992 300CE-24 at auction earlier this year. No rust, full history and 12 months MOT. I'd always wanted a w124, largely for their reputation for build quality and had previously owned a brilliant w123 which was faultless for years but eventually lost to rust.

First month or so was great, absolutely love the car. Then the window motor went, got that repaired, the. The blower, fixed that, then thought I'd get it serviced (6 months after the last one, apparently). The merc specialist basically said it was in a terrible state of repair and there was no way the MOT was genuine. I got a long, long list of things which were needing to be done and went home and went online and sourced them all from Germany. The garage's advise was to get shot of it as soon as I can. But I spent £450 - same price as the garage were getting the blower motor from MB for and bought everything which needed doing. Then a day after the full service it started getting very lumpy whilst stopped in traffic before breaking down. Garage couldn't work it out, thought they'd fixed it but it happened again.
My rationale is that this car is a brilliant brilliant car and just because the market doesn't value them doesn't mean they're not worth putting a few grand into. If it was a 993 or a 964 people would think nothing of it.

My wife however agrees with the garage.

I'd be very interested to hear opinions on whether I'm going to regret this, especially from current or past owners!

Doofus

25,732 posts

172 months

Thursday 22nd August 2019
quotequote all
Buy a better one. I had a facelift E320 Sportline coupe, and I spent a fortune on upkeep which I didn't get back.

If, as you have said (and you're largely correct), the market doesn't value them, where's the sense in sinking loads of money into it? Buy one that somebody has already done that with. Ypu'll pay less than they have.

Edited by Doofus on Thursday 22 August 22:50

BarcelonaLewis

Original Poster:

150 posts

135 months

Thursday 22nd August 2019
quotequote all
That's very sensible. I suppose sentimentality (developed very quickly!) might be clouding my judgement here, but yes, that does make good sense.

swindler

253 posts

178 months

Friday 23rd August 2019
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What is actually wrong with it? (If it's rust free?)

tobinen

9,184 posts

144 months

Friday 23rd August 2019
quotequote all
Yes, what is the issue - just the lumpy running?

Can't that that difficult to fix. I'd be questioning the ability of the so-called Merc specialist if they don't know what's wrong with it.

BarcelonaLewis

Original Poster:

150 posts

135 months

Saturday 24th August 2019
quotequote all
tobinen said:
Yes, what is the issue - just the lumpy running?

Can't that that difficult to fix. I'd be questioning the ability of the so-called Merc specialist if they don't know what's wrong with it.
The lumpy running is due - we think - to the wiring loom being disturbed after the plugs were changed during the service.
The issues which were flagged at the service were pretty broad but the theme seemed to be that everything was worn out - bushes, engine mounts, springs, brake pipes, oil leaks, differential was starting to go.
I paid £1600 at auction and have spent the same again on new tyres, service, parts, and fitting the window motor and blower. I'm inclined to think it'd be better to continue and end up with a car I've spent 5 or 6 k on rather than sell this and spend 6k on a '
good one'

PositronicRay

26,957 posts

182 months

Saturday 24th August 2019
quotequote all
BarcelonaLewis said:
tobinen said:
Yes, what is the issue - just the lumpy running?

Can't that that difficult to fix. I'd be questioning the ability of the so-called Merc specialist if they don't know what's wrong with it.
The lumpy running is due - we think - to the wiring loom being disturbed after the plugs were changed during the service.
The issues which were flagged at the service were pretty broad but the theme seemed to be that everything was worn out - bushes, engine mounts, springs, brake pipes, oil leaks, differential was starting to go.
I paid £1600 at auction and have spent the same again on new tyres, service, parts, and fitting the window motor and blower. I'm inclined to think it'd be better to continue and end up with a car I've spent 5 or 6 k on rather than sell this and spend 6k on a '
good one'
If your specialist can't sort the lumpy running I'd either learn to DIY or change specialist.
Old cars are always in need of something, so DIY eases the pain.

Doofus

25,732 posts

172 months

Saturday 24th August 2019
quotequote all
Later W124s had the biodegradable wiring loom. I had lumpy running, which some 'expert' diagnosed as failing coil packs, so I replaced those and it made no difference. I then bought a new loom from MB (around £600, ten years ago), and fitted it myself. That cured the problem, and the 'expert' told me the failing loom would have caused the coil packs to fail. I didn't believe him and, to this day, I suspect I wasted my money replacing them.

Unless yours is a very late pre-facelift, I don't think you have a biodegradable wiring loom, so you can ignore the above... smile

ShampooEfficient

4,266 posts

210 months

Saturday 24th August 2019
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Always, always check the OVP relay. If that car has one of course. Sorted my 190 of a similar age when I replaced it. biggrin

r129sl

9,518 posts

202 months

Monday 16th September 2019
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300-24 motors don't have the degradable wiring loom.

Lumpy running will be a bad distributor rotor, cap or seal (or all three), maybe a dirty throttle body, maybe a disturbed coil pack. They're not complicated.

To those who say, "Buy a better one", I say such cars do not exist. We don't look after our cars in the UK and that's that. Even the mega-money cars at specialist dealers have lists and lists of backlog maintenance. Get a rust free one, get to know it, get on top of it, stay on top of it. Learn to enjoy the diagnosis of inevitable faults. This is especially so when a car is pressed into use after a long period of inactivity.

T-195

2,671 posts

60 months

Monday 16th September 2019
quotequote all
You can get any parts you need from ECP too.

I have one rather like yours.

Lumpy running as mentioned distributor, leads and plugs. I had intermittent arc on the king lead that caused a lot of problems. Mine has needed very few new parts in the time I have had it.

I think they benefit from being used fairly regularly.

sim16v

2,176 posts

200 months

Wednesday 18th September 2019
quotequote all
r129sl said:
300-24 motors don't have the degradable wiring loom.

Lumpy running will be a bad distributor rotor, cap or seal (or all three), maybe a dirty throttle body, maybe a disturbed coil pack. They're not complicated.

To those who say, "Buy a better one", I say such cars do not exist. We don't look after our cars in the UK and that's that. Even the mega-money cars at specialist dealers have lists and lists of backlog maintenance. Get a rust free one, get to know it, get on top of it, stay on top of it. Learn to enjoy the diagnosis of inevitable faults. This is especially so when a car is pressed into use after a long period of inactivity.
I'd agree with that.

To me, the worst issue is rust, so if yours is rust free, you have a good basis to work from.


Keep your "cheaper" car and get it sorted, base cost is £1600+£XXXX in parts/maintenance.

Buy an expensive one for £5-6k and you'll still need to spend £XXXX on parts/maintenance.

I dare say a lot of the "faults" are normal age related items that you could easily live with, or replace to get the car back to "as new", forgetting the fact that it is near enough 30 years old.

I've had a few "specialists" inspect my cars for potential owners and come up with pages of work allegedly needing doing.
Yes, to get the car back to as new factory spec, but they weren't at brand new cars or prices!



DanMorgan

4 posts

144 months

Tuesday 1st October 2019
quotequote all
BarcelonaLewis said:
Hello all,

I bought a 1992 300CE-24 at auction earlier this year. No rust, full history and 12 months MOT. I'd always wanted a w124, largely for their reputation for build quality and had previously owned a brilliant w123 which was faultless for years but eventually lost to rust.

First month or so was great, absolutely love the car. Then the window motor went, got that repaired, the. The blower, fixed that, then thought I'd get it serviced (6 months after the last one, apparently). The merc specialist basically said it was in a terrible state of repair and there was no way the MOT was genuine. I got a long, long list of things which were needing to be done and went home and went online and sourced them all from Germany. The garage's advise was to get shot of it as soon as I can. But I spent £450 - same price as the garage were getting the blower motor from MB for and bought everything which needed doing. Then a day after the full service it started getting very lumpy whilst stopped in traffic before breaking down. Garage couldn't work it out, thought they'd fixed it but it happened again.
My rationale is that this car is a brilliant brilliant car and just because the market doesn't value them doesn't mean they're not worth putting a few grand into. If it was a 993 or a 964 people would think nothing of it.

My wife however agrees with the garage.

I'd be very interested to hear opinions on whether I'm going to regret this, especially from current or past owners!
Both the 12V and 24V suffer from condensation in the distributors. I own both a 124 Mosselman Twin Turbo with the M103 3.0 12v and a 129 3.0 24v and whenever I feel the "lumpiness" feeling, 9/10 it is the distributors. I have since got in the habit of drying them out when I get the cars out of winter hibernation.

The 24v is a great engine (and very tunable) and as mentioned, it doesn't suffer from the dreaded wiring loom issues. The only main thing to watch out for is the EZL's. The EZL of the 24v engine is very expensive to replace (£500 - £1,000 currently).

alabbasi

2,469 posts

86 months

Tuesday 1st October 2019
quotequote all
DanMorgan said:
Both the 12V and 24V suffer from condensation in the distributors.
This is where I would look first and the insulator behind the rotor. I don't know if your car was affected by the biodegradable wiring harness. Do a compression test also to make sure that you don't have low compression in one of the cylinders.


T-195

2,671 posts

60 months

Tuesday 1st October 2019
quotequote all
alabbasi said:
DanMorgan said:
Both the 12V and 24V suffer from condensation in the distributors.
This is where I would look first and the insulator behind the rotor. I don't know if your car was affected by the biodegradable wiring harness. Do a compression test also to make sure that you don't have low compression in one of the cylinders.
Just try giving it good blast with a hair dryer to dry it out.