Have an air lock in my 1995 c250 diesel elegance. Bought the manual of course, it says the solution to the problem is to bleed the fuel system, but doesn't say if there is a bleed screw or where it is. I need help because she was driving (if somewhat 'lumpy') until yesterday evening!

I would have thought this was a self bleeding system like mine. With the engine running, you can try and loosen the fuel lines to the injectors one by one and see if you get any bubbles. I think your problem lies elsewhere though.

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Limey,

More likely you have a plugged fuel filter unless you have a big air leak in the fuel lines.

P E H

on the 1995 C250...
I can not guess where the fuel system is broken or plugged...

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I can definitely see air in the fuel lines, unfortunately I cant rely on the self-bleeding mechanism - as she isn't running as of yesterday. I keep having to recharge the battery as it runs out of juice pretty quickly when I try to get her started - is there any manual way of bleeding the system, as I reckon ints the air lock thats causing her not to start? Thanks for you repsonses folks.

to save on battery power remove fuel filter & fill it up from a container of diesel. then hold the filter in place without fitting the banjo bolt & fill the filter head with diesel until you see all the plastic fuel pipes are full, then refit the banjo bolt & crank it over it should fire after a few turns. if your system is getting air into it, the most likley place will be from the joints on the plastic fuel pipes between the filter head & fuel pump. the normal procedure is to replace all the pipes. if your car does have the black shut off valve on the side of the main fuel pump the remove that & replace the o ring behind. have just done a C250 turbo diesel this week & fixed its cold starting problems.
hope that helps

Thanks for that - will have a go tomorrow, as the light has gone here. Will keep you all posted!

definitely got more juice out of the battery - thanks for that tip - unfortunately she didn't start. The battery's on charge again, but I'm stumped. The engine just doesn't seem to be catching.

Limey,

Pressureize the fuel tank with an air hose, but only slightly. Maybe 1 or 2 PSI. You might have to block the fuel overflow line.

Check all the fuel lines for a leak. Remove the fuel line going to the IP and see if fuel squirts out, it should. If it doesn't, there is a blockage somewhere. Start at he fuel tank and work your way forward to find where the blockage is.

Warning: If you keep cranking with the starter until the battery goes dead, you may damage the starter. Give the starter enough time to cool.

P E H

Unfortunatley we don't have an air hose, we've tried all the other suggestions - no joy I'm afraid. We're gonna have someone look at the car tomorrow. Appreciate all the help.

I always use the same method for bleeding the fuel system. I remove all the glow plugs and crank the engine for 30 second intervals with the throttle in the wide open position.

When you have a fuel mist coming from each glow plug opening, return the throttle to idle, install the glow plugs and the engine will start immediately.

There are many other methods, but this is the one I use.

I hope this information is helpful...Robert