Occasional Blue smoke

[Steve Chafer]

Can any savy Merc mechanics Help?

did a fairly long journey today London- Bournemouth & back.

Noticed that if I brake or"overun" then accelerate strongly I see a quick puff of blue smoke out the back especially on a downhill gradient.

Gentle throttle openings don't produce this effect.

thinking back I did notice it once before when pulling out of a juction using max kickdown to avoid oncoming vehicle.

Any thoughts as to causes , prognosis & advice please?

much apreciated.

Steve
W124 Auto

 

[Ian B Walker]

Steve sounds a little like valve guides on their way out although I may be corrected here.

 

[Steve_Perry]

Steve sounds a little like valve guides on their way out although I may be corrected here.

I agree with Ian, sounds like your valve guides have worn. They are cheap to buy but will cost a fair amount in labour charges to replace.

My previous car, 1986, W201 190E, used to belch blue smoke if fully booted when cold, not a hint of smoke once the engine was warmed up. I was told that this was caused by worn valve guides. I never did have them replaced in the 4 years that I owned the car. When I asked if it was worth changing them to stop the smoking I was told it wasn't really worth it, due to the high labour charge involved with changing valve guides.

S.

 

[guydewdney]

valve stem seals - or possibly the oil over filled and the oil is going up the breather pipe into the inlet.

as a test - pull off the engine to air intake pipe and block the hole int he intake. stuff the end of the crankcase breather into a bottle of some sort (with plenty of pipe in the bottle and plenty of clearance around it.) - secure bottle with gaffa tape / cable ties / sky hooks.

test drive - this wont damage your engine.. does it still do it? then its valve guides - if not - then its the breather pipe / blow by on your pistons raising crankcase prfessure and forcing oil up the pipe...

 

[Steve Chafer]

Thanks Guy,Steve, Ian,

Had a chat with my local garage, seems like its an early valve stem job,

He feels that best way forward is to live with it for a while and monitor consumption.

Guess that will give me time to save for a recon engine, from Crew engines or similar -'think i'll go for a 2.3 litre in exchange for the 2 litre asthmatic lump I have now.

cheers M8

Steve

 

[Ian B Walker]

i'll go for a 2.3 litre in exchange for the 2 litre asthmatic lump I have now.

cheers M8

Steve

Try a 2.6 or a 3.2 (£3600 from Crewe Engines (non exchanged))

 

[Steve Chafer]

Hullo Ian

thats an interesting suggestion

3K for a new engine on a £ 1,500W124 initially sounds like a p*ss poor investement, however if you look on it as a virtually new car for 3K it makes a whole lot of sense

(the rest of the car is just excellent and yes I totally agree W124 do rock !

the E mail I got from Crewe engines said that 2.3 was the largest option they offered but then again I did write specifically about an EXCHANGE engine.

Could you or anyone who has done this please expand on what other Mods are required to fit a (I presume 6 Clyinder engine) as per your suggestion I'm thinking of beefier springs etc. but I'm no Mechanic.

My W124 is an '200 estate 4cyl.

incidentally I did a run up to Yorkshire & back over the week end, some 650 miles it used no more about 3rd of a litre of oil, so it maybe I have a goodly time to save up for the transplant!

Steve

 

[PJH]

Could you or anyone who has done this please expand on what other Mods are required to fit a (I presume 6 Clyinder engine) as per your suggestion I'm thinking of beefier springs etc. but I'm no Mechanic.

My W124 is an '200 estate 4cyl.

Steve

I would compare the differential ratios too. A 3.2 engine on a 2.0 axle might be a bit low geared. Great acceleration though.

 

[Ian B Walker]

Steve if your 124 4 cyl is carburated then forget it. If its injected then its a possibility. You would need the following.

ECU (ouch £)
Engine mountings.
Different rear dif as PJH surgested.
New roll bar and bushes (front)
Uprated Springs (front)
New radiator as your old one is going to get in the way.
Twin fan unit for the radiator as you would have to lose the engine mounted one (if fitted, not sure here)
And quite possibly a new exhaust.

Think thats about all, anyone think of anything else just add it to the list

Now sit down, work it out and have a large drink, you are going to need it when the total pops up