w124 om 606 questions

[Dave Lewis]

I bought a 1995 E300 diesel estate last week, 200k, fsh, rather cheap
It needs a bit of tidying, and it's due a full service, which I'm doing myself. I'm going to fettle it bit by bit while still running my 2-litre petrol estate, before deciding which to sell.
The day after I collected it, it refused to start eek: )
Large amounts of air visible in the various flexi pipes to and from the filter.
I decided to start with new plastic fuel lines, (about £30 for all 5 from the stealer), pre-filter and spin-on filter. I replaced the four fuel lines I could reach, and now it starts and runs fine, so maybe it's Job Done. The old pipes were brittle, and the o-rings on the connectors flat and hard, no wonder it was pulling air in. However, one of the fuel lines, from thermostat to filter, is impossible to fit without removing at least the top part of the inlet manifold. Should I take the opportunity to remove the entire manifold, clean the EGR gunge out, and have a general poke around the vacuum tubes, glowplugs etc? Is there anything particular to watch out for when removing it, and anything else worth checking while it's off? How long do glowplugs typically last, and how much do they cost?
I notice in the service book that the recommended oil change interval is 9000 miles. This seems rather long. Also, what make and spec engine oil is good for these engines? Is there anything else routine to replace at this mileage? This is the first diesel I've owned since my Scania 11-litre, and so far I like what I see.

 

[Dieselman]

Well done on sorting the problem.
I think you will get to the retaining clip without removing the manifold if you use a long screwdriver to push it in then prise up the pipe.

Other than changing the oil for a synthetic diesel specific, MB 228.3 is recommended but not necessary as all decent oild will surpass that, I wouldn't do anything to the engine other than change all the other fluids.

Me thinks you will definately be selling the 200 once you start using the 300.

 

[Dave Lewis]

Thanks for the quick response Dieselman!

I think you will get to the retaining clip without removing the manifold if you use a long screwdriver to push it in then prise up the pipe.

Just realised I meant the pipe from the filter to the back of the injector pump. The pipe in question has a push-fitting on the filter end, but a bolt'n'banjo on the pump end. If I remove the washer bottle, I may be able to reach it with a bit of contorting. I'll let you know. Part of me wants to leave the manifold alone, but having seen the thread on EGR gunk, I'm tempted to have a look, especially as this could be a keeper.....

 

[Dieselman]

You don't need to replace that pipe as it is the low pressure return back to the tank, no air can be drawn in there.
Only replace it if it leaks fuel, which it wont.

Just do these jobs if you get a glowplug down.

 

[Dave Lewis]

Thanks! I'll save my knuckles then, and get onto changing the fluids.

 

[Parrot of Doom]

Might be an idea to remove the manifold and check the diesel spill pipe, mine was rotted to hell and drowning in diesel when I bought it. Its only pence to replace it. Runs between each cylinder along the top of the engine. In fact you should be able to see part of it near the front of the engine without removing anything.

/edit: Its here:

Also take a look at the belt tensioner at the front of the engine. Its a spring and a shocker. If its making a noise, you'll need to replace it.

Leave the glow plugs alone. Unless the orange light stays on for 1 minute after starting, they're fine. If they need changing, you're really best letting a Merc indie do it as they can be notoriously difficult to remove without breaking.

 

[Dave Lewis]

Ah, I wondered what the braided small-bore pipe that tees off the main fuel feed was. It seems in good nick, but I'll keep an eye on it.

The belt tensioner seems to operate just fine.

Yep, I'd heard the glow plugs could be a b**ch to remove. I'll wait until I have a problem, and pass it over to the indie.

Thanks very much for the help.

 

[Vlad]

Dave,

Every 10,000 miles or so, I used to sling a litre of automatic Transmission fluid in with a tank of fuel.

Tranny fluid does a very good job of cleaning the fuel lines and injectors and does no harm to the engine/injection pump.

I would then take the car for an Italian Tune Up.....ie lots of high rev driving, just to clean out the injectors....its amazing how much smoke comes out, but after that you rarely get a puff of smoke even on full bore up changes.

By the way these engines run very nicely on Veg Oil....I ran mine for over 30,000 miles on a 50/50 mix and it ran perfectly and at 0.39p per litre for Veg it was cheap motoring. The only thing you have to do is change the fuel filter after the first tank of Veg as its more viscous than Diesel and does a good job of scouring the crud off the fuel lines that then ends up in the filter....after that its all plain sailing.

Great engines....theres a W124 down at my local MB Specialist that has 498k on the clock and its still going strong and being used as everyday transport.

 

[lukebowman551]

HI guys, i run a W124 E250 diesel (1995). I had a similar problem with air being drawn into the system but once i replaced the fuel line that goes into the top of the pre-filter it has more or less been ok. I've been running my car on a 50/50 mix of diesel/veg oil but i noticed a bit of power loss once it got a bit colder, i think it's down to one of the plastic fuel lines so i'm replacing the lot. Nice to hear the thing about the low pressure return pipe with the banjo at the end as mine has a clip on both ends instead of a banjo on the fuel pump end and the stealership reckon you can only get the version with the banjo, i'm picking it up tomorrow so i will see then.

Also, i've got a problem at the minute to do with the fan belt. I had a belt snap last week so replaced it. The belt had only been on about 6 months and was showing signs of wear on the back side of it. I have now replaced the belt but the back of it i definately rubbing on something already and it's only been on a week. In my opinion the belt is too tight, ie too small (the wrong belt). The tensioner pulley assembly is at full stretch, ie the damper is fully compressed and the spring is at full stretch. I think that the tensioner pulley is so near the crank pulley that the backs of the belt are rubbing against each other causing the wear. The belt that i replaced a while back was considerably looser.

Can you guys help? I think either the spring isn't doing it's job on the idler pulley assembly or that the belt supplied is the wrong one. My car is without air conditioning. When i pulled on the belt it is very very tight so i don't think it's the spring.

Have i been supplied with the wrong belt? has anyone heard of this before?

Any advice is appreciated.

 

[Dave Lewis]

Dave,

Every 10,000 miles or so, I used to sling a litre of automatic Transmission fluid in with a tank of fuel.

Tranny fluid does a very good job of cleaning the fuel lines and injectors and does no harm to the engine/injection pump.

I would then take the car for an Italian Tune Up.....ie lots of high rev driving, just to clean out the injectors....its amazing how much smoke comes out, but after that you rarely get a puff of smoke even on full bore up changes.

By the way these engines run very nicely on Veg Oil....I ran mine for over 30,000 miles on a 50/50 mix and it ran perfectly and at 0.39p per litre for Veg it was cheap motoring. The only thing you have to do is change the fuel filter after the first tank of Veg as its more viscous than Diesel and does a good job of scouring the crud off the fuel lines that then ends up in the filter....after that its all plain sailing.

Great engines....theres a W124 down at my local MB Specialist that has 498k on the clock and its still going strong and being used as everyday transport.

Thanks for that Vlad. I like the sound of the 'Italian tune-up'
Glad to hear you've successfully been running on veg oil, that's another reason I've been looking for one of these cars.

 

[Vlad]

Luke

Re the belt problem on your car.....its quite a common problem on these diesels for the tensioner to start packing up on these engines.

It then causes one of the pulleys to go out of alignment causing the belt to rub and if its bad, for it to snap the belt, as happened on yours.

If you look in the engine bay behind the radiator and look at the various pulleys you will probably see the small one in the middle to be slightly out of alignment, which causes the rubbing on the belt....you can notice this more when the belts are rotating.

I had to have mine fixed on my 300D and its quite a big job as you have to undo the main crankshaft bolt which is on very tight....my local MB specialist did it for me and he told me that most diesel engines of this age are now having to have it done.....all in all for the work that needed doing it wasn't that expensive...you just have to have the right tools and know what you are doing.

 

[kth286]

luke

If you go to the main dealer with your VIN and tell them 'no aircon' you will get the correct belt.

If you go to a factor, there is NO guarantee of getting the correct belt.

 

[lukebowman551]

I checked out the different types of belt available for this engine as recomended by someone in a different thread that i started. It says that there are 2 different belts that are used for non air con engines and they differ in length. 1 belt is 50mm longer than the other. I have checked my belt and it is the shorter one. I'm going to go to GSF in the morning and get a new, longer belt. I might get a new tensioner pulley while i'm at it. I'm going to have a look at the car in the morning before going to GSF and decide whether to bother getting the pulley.

 

[lukebowman551]

Got my new belt and tensioner and damper. Also fitted new fuel line so should be able to start using veg oil again without leaks or air entering the system.

Does anyone know where to get the MB tool for holding the waterpump pulley still so that you can remove the fan? Or any tricks for doing this?