W124 Engine Conversion? Please read! Need help!

MJK 24

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Well, I've always admired the W124 range.

Yesterday, I find myself with a couple of spare hours wandering around the local Motor Auction.

I spot a W124 230e with no numberplates on. It had just had a cherished transfer by the DVLA. I am friendly with the staff and they let me see the logbook. 1 owner from 1993! They pass me the keys. Open the header tank - nothing. Pull the dipstick - mayo galore!

Head gasket has gone :cry:

Bodywork and interior are lovely. No rotten arches!

Flat battery so I couldn't start it.

I hang around until it is started up and it starts easily enough and sounds ok. It's showing 111k miles. Looks about right.

They leave it running with no water for about 10 minutes :cry: I wanted to run over and turn it off!

Anyway, I buy the car for £150 and I've trailered it home.

Fill with water and idle. Seemed to warm up ok. Temp went to 80 or 90 over a normal timescale. Drove it around the yard (literally half a mile) just to see if the auto 'box is ok (it's lovely) and pull up. Starts to vent all it's juices out the header tank cap.

When reved, there's a lot of blue smoke but I think this is a result of the thin and runny 'Mayo' getting past the valve stem oil seals.

1) Am I right in thinking the original problem with this engine is a blocked /failed thermostat?

2) Am I right in thinking that the water pump will be driven from the timing chain? (If so the pump must be ok unless the impellor has fallen off?

3) Is this engine a viable prospect to repair? £30 head gasket. £30 head skim. £20 head bolts.

4) Am I a complete lunatic for wanting to put in a 5 or 6cyl diesel from a 250 or a 300d?

5) Do all W124's have the same Autobox?

6) Do all W124's have the same engine mounts (ie the same mounting points on the inner wings/bulkhead?

PS I know it'd be easier to buy a 250d but this car is too good to waste and the chap who was bidding against me was from the local salvage company :cry:

:)
 

Number_Cruncher

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Your Mercedes
1995 W124 E300D TE
1) I doubt it, but, it's worth checking the thermostat anyway

2) No, it's driven by the belt

3) I suspect you'll pay more for the parts than that, but, if you're doing the work yourself, it should be viable. It really depends upon what you find inside when you lift the head off.

4) Yes. If sanity continues to elude you, make sure you swap engine, gearbox, propshaft, all ancilliaries, and all diesel specific electric, cooling, oil cooling and vacuum parts.

5) No - hence the advice to swap engine & gearbox together. Speedo drive and propshaft couplings then become an issue.

6) I'm not sure, but, I suspect not.
 

Bolide

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Website
www.w124.co.uk
Your Mercedes
BMW 525 Diesel Touring
I'd throw the engine away if it's smoking and put in an identical engine

Converting it to diesel will be a bigger job that you think

Nick Froome
www.w124.co.uk
 
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MJK 24

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Thank you for the advice so far.

I must admit, having a second look this afternoon has lead me to the path of sticking with the existing engine!

I shall remove the head and report back!
 

Alex Crow

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Your Mercedes
W169, W124, w202, W203, KTM 250 EXC, VW T25 camper and a Polo in a pear tree
you may well find a destroyed cyl head. check for warp and tracked grooves at cylinder sealing surface on head, especially cyl no.4 at o/s (near oilway). a new head could be £50-100, bolts usually fine if you check length next to specs.

blue smoke is usually valve stem seals on these 102 engines, a fairly easy fix (1.5-2 hours at our workshop)

the diesel swap is only really viable with a donor car, and yes, the engine/box will fit your car.
 

teddycatkin

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Your Mercedes
W107-SL W124-220te W123-230e W201 2.0
These engines are very robust --whip head off and be surprised ?
The skim and gasket set will probably do the job --I would renew w/pump and belts while doing it --it will be good for another 111k when done.
 
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MJK 24

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If the weather is decent tomorrow, I'll remove the head and we'll soon see what's what.

I shall report my findings.

Thank you for the additional advice.
 

Alex Crow

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W169, W124, w202, W203, KTM 250 EXC, VW T25 camper and a Polo in a pear tree
if the head needs welding and machining it could well be cheaper to get a s/h one. with the car coming from an auction and a trip round the yard pressurising the coolant, expect the worst - someone has already condemned it once.............
 
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MJK 24

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Well, it's raining, the Grand Prix is on and I'm shattered. Therefore, the head will remain in place for another day!

I have however removed the thermostat. Good news and bad news.

Bad news first: I put in in a pan of water and sat it on the hob. Thermostat didn't open even when the water was boiling. I think that the faulty therm. caused the car to overheat and the head gasket to fail.

Good news: There doesn't appear to be any mayo sludge in the cooling system. Just the oilways. Just means there's less to clean out I guess.

The engine must be a heavy breather as I removed the air filter cover and there's a small amount of mayo up there. Nothing outrageous for the mileage of the engine though.
 
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