Thread: Disco 300tdi Leaking Lift Pump

Karcraft, comes with a couple of new olives as well.

I don't know about simple fit, as you said, it is straightforward, just a bit of a stretch to get your arms in there.

Pump arm should be down when there isn't a hole in the gasket, fuel pressure and gasket should put it in that position.

Don't know about the priming thing, but most agree that priming is usually the last straw for a lift pump gasket.



Cheers
Simon

Howdy: To make life easier, give your engine a good wash with some degreaser - then wipe the problem area down. Then inspect to see if it really is the pump,or the fuel line, or the filter or the return lines. All of these things (esp the return lines) can leak small amounts of fuel. A set of pipe spanners would also be a good idea when/if you have to undo fuel pipe connections.

Langy

There is definitely no leaks around the fuel filter - completely dry.

I wiped my hand under the lift pump and I do get diesel on my fingers...but that's not to say it isn't seeping down there from somewhere else. The engine is reasonable clean, but I will clean it a lot better so I can determine what it is.

Also seems suspicious because I changed the fuel filter and used the lift pump to prime and I have read lots of posts that suggest never touching the lift pump.

I looked a little closer and it looks like I need to undo the fuel pipes from the injector pump and the injectors to have more room to work. Nothing special required here?

And what are these special spanners you soke of Langy? They just look like normal nuts?

Pete

One more thing to ask...I only noticed the leak because I was at my parents house and the car was parked facing downhill (steep driveway). It doesn't appear to leak much at my house on a reasonably flat driveway.

It had a full tank of fuel and was facing down a steep driveway. Could this also contribute to making it leak more than if it was flat? It would help explain why I haven't ever noticed it before.

By the way, thanks for the help.

Pete

Pete

Changing the lift pump is a pretty easy job. Make sure when you get a new pump you get the olives for the fuel lines then just bolt it into position. I had to replace mine when the fuel pipe from the filter fractured where it joins onto the body of the pump. There was a small crack at the base of the metal pipe where it actuallu joins onto the pump itself. When I noiticed it I had been on corrugated roads for a week or two. When I noticed it it was not just a few drops but a fairly steady stream with the engine running but I suppose it started small and got bigger.

As a side issue when I noticed it I was between Birdsville and Nocundra with no chance of getting a new pump. I did a dodgy repair with Quicksteel epoxy and it was still holding perfectly a month and a few thousand kilometres later when I got round to replacing the lift pump.

I haven't had to prime the system after changing a fuel filter, it's always started no problems.

You should be able to test if the lift pump is shot by opening the bleed bolt on the top of the fuel filter and pumping the arm of hte lift pump. If it is working fine fuel should come out of the hole.

The arm of the lift pump should also have a reasonably positive feel to it.

Cheers
Simon

Pete,

Be sure to check the fuel lines from the filter to the pump.

The fuel lines all looked OK - but I can't say with 100% certainty they don't have a hairline split in them somewhere.

When I searched the archives someone mentioned they replaced one of them with a hose from Pirtek. All the fuel lines seem to be this hard black plastic stuff/hose - does anyone know if they can be replaced with a generic fuel hose of some sort from a place like Pirtek?

If I'm going to the effort of changing the pump, moving all those old pipes around might brake them anyway.