smoky W124 300D estate (1993 car)

[thoasha]

I haven't posted for a while but I've gone through a couple of petrol W124's in last two years and have just got a 300D which I knew to be smoking when I viewed and before purchase. Having had other diesel cars I do know about glow plug issues, but I'm just wondering if this is the only problem here? The car starts lumpy but after about five mins settles down but still smokes. The engine sound is good (like alovely straight six should sound) when revved, but terrible when idling. There's two noises - a sort of metallic/bearing type rattle from front end - maybe a bearing in one of cogs on pulley/belt? and the other is when switching car off a sort of a shudder - like a worn engine mount maybe.

Now for another a strange sort of thing - which is probably the reason for the whole (the smoke, the noises, the lumpiness) - the car is happy to cruise at 75ish on motorways but regularly loses power like a starvation of fuel or something then resumes to normal power again. When it loses power you just have to go into the slow lane and wait while the engine gets back on song as it leaves you travelling around 45-50mph.

So guys, plenty there to think about and I hope the fix isn;'t expensive! I feel a change of one or two gloplugs, new airfilter, fuel filter and an oil change might help a bit, but I await your "professional" advice based on your experiences

Thanks

 

[Doug1234]

Fuel filters , fuel tank strainer, and lastly the fuel tank cap itself not breathing.
Classic signs of fuel restrictions on 300d are a lurching at certain speeds / revs , drop the revs a bit and it will drive all day but as a week or so goes by the amount of revs you can use before problems drop.
It will pull air in through fuel lines (visible in pre filter) if tank strainer is blocked.

 

[thoasha]

Fuel filters , fuel tank strainer, and lastly the fuel tank cap itself not breathing.
Classic signs of fuel restrictions on 300d are a lurching at certain speeds / revs , drop the revs a bit and it will drive all day but as a week or so goes by the amount of revs you can use before problems drop.
It will pull air in through fuel lines (visible in pre filter) if tank strainer is blocked.

Thank you very much for this uncomplicated reply. These issue sound like something I can address myself, however, would you confirm whereabouts various "filters" are located? Once again, thanks. (Citroen XM 2.1TD and V6 owner for 15yrs!) but love the bigger older Mercs of same era so just getting to know them properly.

 

[dbanbery]

Thank you very much for this uncomplicated reply. These issue sound like something I can address myself, however, would you confirm whereabouts various "filters" are located? Once again, thanks. (Citroen XM 2.1TD and V6 owner for 15yrs!) but love the bigger older Mercs of same era so just getting to know them properly.

the main filter assembly at the front of the engine bay, there is a tiny strainer - see #26 here you undo the 10mm bolt on top

that may be full of black cack.

make sure the o-ring is Ok and present, otherwise the car will never EVER start.

 

[brianbrian]

You will also have a small inline fuel filter, under the air filter that needs replacing , about £2.00 each. Hope this helps

 

[thoasha]

evening dbanbery and thanks again for advice. Well I took to trying what you suggested - not overly successful (I didn't get all the stuff done). I looked at the diagram to locate the fuel strainer but I feel I must have misread it. I did take off and clean the little fuel connectors feeding into and out of the top of the filter though. I cleaned out the air filter too. All easy stuff really and I think your idea is easy too but I can't seem to find the bit you pointed me to! (I'm not normally that stupid - honest - as I'm a very practical guy,.hands on etc). Can you photograph said area and pencil in the bits perhaps? So sorry for nuisance. Anyway, I did test the car afterwards and I ended up stranded and limped the 8miles back home with my son at ready with tow rope and jump leads (the latter because when engine died I had to turn it over so much to start again that the battery was under strain). There's blue smoke emitting when starting/churning over. Once settled after running it's not as bad but not perfect. Then when on the run the engine is lovely until suddenly the revs reduce and, unless you ease off the throttle, the engine cuts. It doesn't seem to like fuel. That's what happened first time on the run - I was cruising nicely and then decided to floor it to put revs up and keep a lower gear in an effort to put more fuel through and somehow clear the cobwebs but it just died. After that it was five more stops and starts to get back home. It's definitely a fuel issue so I've no doubt about your diagnosis - just need to get a clearer idea of where stuff is. I can follow pictures! Also, should the engine sound "tappety" all the time, like a van engine? My Citroen XM's don't - just the normal diesel idle. There's also a sort of a scobing noise from up front (similar to if a brake shoe is stuck on a bad disc and it's rubbing at intervals as it turns) but this is in the enginebay. The bearings on some of the wheels within the V-belt area? Look forward to your reply and further advice.

 

[dbanbery]

bear in mind this is without the metal cover plate, but you should still be able to see it

 

[thoasha]

Thanks dbanbery

the pic you attached I can't open/it's not showing

 

[thoasha]

Hi again, got it opened now! BUT this is from a 250D and the filter housing etc is totally different on my 300D

 

[dbanbery]

Hi again, got it opened now! BUT this is from a 250D and the filter housing etc is totally different on my 300D

the filter housings are the same on the OM606 and OM605

can you post a pic? with your car being a 1993 does that mean it isnt the OM606? i cant remember the year in which they were first produced

 

[thoasha]

ENGINEBAY E300TD (not Turbo! I understand) 1993

Hi dbanbery

see attached for pic of front of enginebay

 

[thoasha]

300D

Hi again bdanbery
I've checked now and it's a 603.912 engine 2996cc 113bhp

Hope this resolves the mystery

 

[dbanbery]

Hi again bdanbery
I've checked now and it's a 603.912 engine 2996cc 113bhp

Hope this resolves the mystery

Yes its an OM603. I dont know these engines greatly but i would uspect that the small filter in the main filter housing doesnt exist, and that there is an inline filter elsewhere as mentioned by a previous contributor. that and possibly being an ide to check the filter strainer. otherwise i'm not completely sure. did you replace the main fuel filter in the engine bay?

 

[thoasha]

Thanks

the main filter was replaced 7k ago. Yes there is an inline filter just below the airfilter box (only seen when box removed) so I intend to get to it and see if it's all gunged up.

 

[Triv]

There was quite a long thread on here 2 or 3 years ago about a 603 that ended up having a new CHG after problems very similar to yours, that were caused IIRC by a dodgy injector or 6.
I'm sorry I can't remember more and I hope this post doesn't make you panic!
He had the injectors rebuilt but had left it too long.
Have a search, it's on here somewhere.

Your issues do sound like a fuelling problem, although I'm not too sure about the funny noise from the front. Can the timing wander on and off?

 

[dbanbery]

There was quite a long thread on here 2 or 3 years ago about a 603 that ended up having a new CHG after problems very similar to yours, that were caused IIRC by a dodgy injector or 6.
I'm sorry I can't remember more and I hope this post doesn't make you panic!
He had the injectors rebuilt but had left it too long.
Have a search, it's on here somewhere.

Your issues do sound like a fuelling problem, although I'm not too sure about the funny noise from the front. Can the timing wander on and off?

Triv,

Whats a CHG?

 

[Triv]

Cylinder Head Gasket.

 

[dbanbery]

Cylinder Head Gasket.

LOL.

Too many acronyms.

I wouldnt fancy doing one of those on a 603 or a 606, expecially when thinking about torquing the head bolts up.

 

[thoasha]

Well guys we'll get to bottom of it sooner or later and hopefully it's just fuel issues. By the way, the fuel tank - somebody fitted a non-standard tow bracket on which seems to run straight under the big allen nut that I may need access to to do a drain or look at filter .Am I right in thinking this (i.e. that nut gives access?)

 

[thoasha]

took off the inline filter below the airbox, cleaned the filter out as best could (it's a sealed unit but a wee bit translucent so could see what looked like a spongey sort of filter inside -although that maybe gunge but don't think so) replaced and tried car again. Started lumpy again, ran /drove ok at lowish revs but on way back from test I floored the throttle and very soon after the engine died again like before. Churned it over on/off for about 5mins to get going and got home ok so not cured yet. Next ? The fuel tank? I've not had any success with where the rest of the inline filters are or the one at the tank - can someone help on this please?

I'm also going to check the glowplugs.

Also, that noise - like a grinding of an uneven disc/drum brake which has seized - coming from up front somewhere is still there. Ideas?