e300td lift pump

[bonez59]

Hello again,
E300td lift pump, any idea of cost of a new one? or they rebuild able unit? Pulled the pipe off between the lift pump and the main pump and ran car and not alot of derv came out. So taking that aint working right

Almost got my hands on the chip flashing hardware and soft for my car and a pile of blank chips. Can start mapping it soon once got it running properly as stock.

So just weighing my options


Thanks ian

 

[Dieselman]

Pull the lift pump apart as there is nothing to it, just a piston and spring driven by a pushrod off the IP camshaft. There is a single one way valve as well.

 

[Ian B Walker]

I have a spare FIE pump from a 300D (W124) if it is of any use

 

[Number_Cruncher]

Which pipe *exactly* did you pull off?

The fuel route isn't exactly obvious....

 

[bonez59]

I pulled off the pipe that comes off the lift pump towards the front of the engine bay going into the top side of the fuel filter housing.

If the lift pump is the same then how much would u want for it? I can't pm yet.

Thanks ian

 

[Number_Cruncher]

Sorry, I don't have a picture of the fuel layout in front of me.

However, the lift pump output is from the port which is closest to the injector pump body.

Although the lift pump is operated by a rod from an eccentric on the injector pump camshaft, it actually pumps on the *return* stroke, as the piston in the pump is moving towards the injector pump.

 

[bonez59]

ok thanks N,C Defo took off the right side.

 

[Dieselman]

Check the spring is operating the piston fully, otherwise it has to be the one way valve.

 

[bonez59]

Oh NC, my lift pump is as dieselman said , mine runs off the cam not off the diesel pump..
OK ill take it off and have a look. Thanks again DM

 

[Dieselman]

^ NC means an elliptic cam on the diesel pump, which is correct.

Are you sure you have the diesel pump not the fuel heater?

 

[Number_Cruncher]

It does sound like you pulled the correct pipe off.

Are the primary filter and the tank strainer clear?

I ask because there's precious little in the lift pump to go wrong.

 

[Alex Crow]

Having read the thread, I am puzzled as to what problem we have here - is the car running OK?

The OP's description of which pipe was disconnected from which component are not yet clear, despite the attempts of others to clarify...

As above, never known a lift pump to fail on these engines, or even the cdi motors for that matter.
The common issues here are with leaking fuel pipes, fuel shut off valves, delivery valves and fuel heaters.

 

[bonez59]

Huuum after reading what u lot have put, im starting to wonder if ive been a ****, and taken off the wrong pipe. Fuel lines runs from the rear of the car to the front, comes into the engine bay, runs around the side of the engine into a black thing on the side of the head, between the inj pump and the rocker cover. Then pipe runs out into the top side of the filter housing. Is this the lift pump or a diesel heater? Did know the mercs ran a diesel heater.
Sorry if ive been mistaken

 

[SilverSaloon]

this may help

http://www.mbclub.co.uk/forums/engine/105924-om606-lift-pump-re-assembly.html

 

[Number_Cruncher]

Huuum after reading what u lot have put, im starting to wonder if ive been a ****, and taken off the wrong pipe. Fuel lines runs from the rear of the car to the front, comes into the engine bay, runs around the side of the engine into a black thing on the side of the head, between the inj pump and the rocker cover. Then pipe runs out into the top side of the filter housing. Is this the lift pump or a diesel heater? Did know the mercs ran a diesel heater.
Sorry if ive been mistaken

That's the diesel heater - it's on the suction side of the lift pump, so, you would not expect to see any fuel being pumped at this point in the circuit.

 

[Dieselman]

Pull the pipe off the main filter nearest the washer bottle, that is the diesel flow pipe iirc.

 

[Alex Crow]

I did wonder if we were on the same page - what propblems do you have with the car?

 

[bonez59]

Lack of fuel. Lift pump isnt doing nothing.
Changed fuel filter and it wont draw the fuel up, got to put a manual hand pump on the return line. Some one has put a electric valve on the return pipe, so turn the ign off and the valve shuts. Ign on and the fuel can flow back to the tank. Any reason that mgiht be there??

Thanks

 

[Alex Crow]

Lack of fuel. Lift pump isnt doing nothing....

I doubt you have a lift pump problem, I have listed the common causes of these cars not starting due to lack of fuel.

There was a Mercedes mod available incorporating a secondary fuel shut off valve, its only purpose is to help prevent fuel draining back to the tank when the engine is turned off - sounds like it is working.

When the car is running, are there any diesel leaks at all, even slight ones?

A tip for those with diesely pumps and pipes who want to pinpoint leaks, spray the 'wet' area liberally with brake cleaner until it is totally diesel free, then run engine.
If there are no external leaks you need to consider all the pipes and o-rings etc before the lift pump, which is probably fine.

 

[Number_Cruncher]

If you fitted the new fuel filter dry, then, it will take ages to fill when you're cranking the engine over. If this is the case, there's possibly nothing wrong at all.

If you haven't done this already, then, I would suggest renewing all of the O ring seals in the low pressure fuel system - all those on the ends of plastic pipes, the one under the pre-filter, and the one behind the shut off valve. Then, having spent mere pennies, you'll know they're OK. Those seals are by far the most common problem.