Indie Merc Specialist

[Dunx]

Does anyone know of an independant Mercedes specialist in the Livingston (West Lothian) or surrounding area (Edinburgh, etc)?

Still having starting problems with my '97 E300TD. It still seems to be drawing air, no matter how much fuel is in the tank. I presume the fuel hoses around the fuel filter are the culprits but need to get this checked out.

Many thanks,

Duncan

 

[television]

How do you mean, drawing in air, what is the car doing

Malcolm

 

[Parrot of Doom]

Take the fuel filter off, and check the seal around the thread is good. 5 minute job. You should be able to see any air in the pipes around the filter.

 

[Dunx]

Malcolm, there appears to be fuel leaking from somewhere around the clear fuel lines that go between the fuel filter and the various parts connected to the injection pump (shutoff actuator, etc).

The car has been extremely difficult to start on three occasions from cold, the first time this happened I presumed I had run out of fuel as the reserve light was on and the car was parked on my drive on an incline, nose up. The last couple of times I have had a full tank of fuel. It always seems to happen when the car is parked on an incline, nose up.

The engine will crank but will not fire. It seems like fuel starvation, so after reading previous posts on this forum, I assumed it may be pulling air into the fuel lines, hence the difficulty starting. It will eventually splutter into life after prolonged cranking, of around 30 - 40 seconds and leaves me with a nice puddle of diesel on the drive, which looks like it's coming from around the injection pump area. Once the car is started, it runs smooth and will start fine when warm, and most of the time from cold. Like I say, it's happened three times over the last month, all from cold.

Am I right to suspect the fuel lines around the fuel filter and injection pump, or am I way off the mark?

Many thanks,

Duncan

 

[Dunx]

Parrot, I'll give that a try. The fuel pipes are fairly old and grubby. It's tough to see if there's any air in there.

 

[Bolide]

Air in diesel

This is a common complaint, particularly when the car's been parked nose-up. There are lots of posts in this forum & others regarding it

The O-rings on the fuel pipes round the filter / pump assemblies go flat with age and tend to leak. The leak is normally started off by someone disturbing the pipes, perhaps to change a fuel filter

You can buy the O-rings from the dealer for about 80p each. There are two sizes. I recommend replacing all the ones you can get to. Some people recommend smearing them with grease to make a better seal. As grease can attack rubber over time I'm not sure if I agree 100%

Replacing the O-rings is fiddly - and it helps if you have small hands - but it's eminently DIY-able. If you're doing it I'd recommend replacing the fuel filter and the fuel pre-filter while you're at it. But prefill the filter with diesel before fitting it and be prepared for lots of cranking to get the thing to light

Once you've replaced them all you should no longer get visible air bubbles in the clear plastic pipework

There is an MB tech note regarding installing a one-way valve in the system when aftermarket immobilisers are fitted. It might be a good move if you continue to have problems

The reason they are so difficult to start when they have air in the system is that the injectors need a certain pressure to crack them open. If there's an air bubble in the injector lines the air will compress and the pressure in the line won't crack the injector. It needs a stiff column of nice incompressible diesel to get them to crack open


Nick Froome
www.w124.co.uk

 

[Dunx]

Thanks Nick. Do you think it's worth the hassle of removing the intake manifold to get to the less accessible connections? Would it be worth replacing the plastic pipes while I'm in there?

Thanks again,

Duncan

 

[Bolide]

Inlet manifold

Duncan

It's a fair old job to get the inlet manifold off - I've done it on a late W124 non-turbo diesel - but it's not rocket science and it would let you get at everything

Problem is, once it's off you find that the tracts going to the inlet valves are clogged with gunge and you'll want to clean them. But because some valves are always open you may push gunge and/or cleaner into the cylinder

If you want to tackle it, take the whole lot off, clean the inlet manfold assembly (which will be filthy), clean & (I suppose) lubricate the EGR & manifold tuning butterfly valves, then do each cylinder inlet tract in turn by turning over the engine till both valves are closed. Carb cleaner & an airline would be handy here. I've never done this but it's how I'd tackle it

The engine will run with the inlet manifold off. It's noisy though! The throttle pedal won't work because you'll have removed the arm that holds the outer part of the throttle cable

I'd replace any pipework that looks at you funny but don't go mad - it probably just needs new O-rings. The EGR pipework under the inlet system has little black plastic T pieces that decay with age & will split. They probably will need replacing

You'll need a good torx driver for a socket set for the manifold bolts. Everything else is straightforward. This is obviously the opportunity to replace bad glowplugs but go carefully - snapped glowplugs aren't fun. Also check the bleedoff pipes from the injectors aren't leaking


Nick Froome
www.w124.co.uk

 

[Dunx]

Thanks for the help Nick. I'll leave this until I can afford a weekend at it!

My T210 has the electronic throttle mechanism so this shouldn't cause a problem. I had the glow plugs replaced a few months ago as at least one was faulty, which is probably how the leak was introduced in the first place! Leak-off pipes were also replaced as one was leaking.

Thanks again,

Duncan

 

[MerChris]

Original question

Dunx,

In case you still want an answer to your original question, I use Deutsche Marque based in Dalkieth area. So far they have been good. Give clear costings and stick to it. They also give me clear information on work done/needed. They are always busy and the workshop reassuringly full of W124's last time I was there.

Taking the car back next week as something is not right with the rear n/s brake since they fitted new disc/pad set a few weeks ago - have developed an irritative squeal in the rear n/s wheel which may be related. We'll see - keeping an open mind.

I would be interested in knowing if there are any other indies in the area you mentioned - I'm in Falkirk myself but figure I'll have to travel some way to find a decent indie! Let me know what you find out and good luck sorting out your fuel problems (I also have hassle with the cold start as well but hope it's something simple, as I ave no idea about working on cars )

Cheers

Chris

 

[lee james]

I have a 1997 W210 E300TD I had trouble starting in the morning and especially when parked slightly uphill when the front is above the rear.

I have noticed air in the clear pipes. I have changed all of the clear pipes and the O rings with it, and have replaced the two pipes leading from the fuel tank. The clips were also replaced. I have also replaced the glow plugs.

But there are still air bubbles in the pipe, resulting in the same problem when starting first thing in the morning.

Does anyone know if they think that I am having problems with the fuel pump? Or fuel filter (as I have not replaced this as it has been replaced recently)?

If anyone could help, your comments would be very much apprciated, thank you.

 

[television]

the remedy here is to check the feed and return pipes.
Clamps must be fitted to all fuel lines,just as imortant on the return to tank line.

Malcolm