What causes 300TDi lift pumps to fail?

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Jongould

Jongould

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I got me a disco at the weekend with a suspect lift pump fault, I checked it out and yep, nothing from the pump so I bought it and when I got it home I changed it, the old one was kaput and the new one was all good, worked fine, primed up e.t.c. and ran beautifully for the drive home. Today it started doing the same thing as before and when I have looked into it its the lift pump again!!

Now am I unlucky with this one? It was a Fuelparts pump, is it best to go genuine? Or is there something else that can cause the to fail this quick?

Cheers

Jon
 
Do you run it on jungle juice? Lift pumps typically have inaccessible internal filters which can clog up, especially if you run it on used jungle juice. It's also possible that you may have sucked up crap from your tank (have you been running it low on fuel?) I'd recommend changing the fuel filter too for good measure.

Some Delphi lift pumps have removable heads which you can unscrew to access the internal filter.

I'd recommend this:
Land Rover Defender 300 TDi Fuel Lift Pump DELPHI - JGS 4x4 Land Rover Parts

You may also want to fit an inline fuel pressure gauge (can get them on Ebay and they are easy to fit) so that you can keep an eye on the fuel pressure.
 
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RichM said:
Do you run it on jungle juice? They have internal filters which can clog up, especially if you run it on used jungle juice. It's possible you may have sucked up crap from your tank (have you been running it low on fuel?) I'd recommend changing the fuel filter too.

Some Delphi lift pumps have removable heads which you can unscrew to access the internal filter.

I'd recommend this:
Land Rover Defender 300 TDi Fuel Lift Pump DELPHI - JGS 4x4 Land Rover Parts

You may also want to fit an inline fuel pressure gauge (can get them on Ebay and they are easy to fit) so that you can keep an eye on the fuel pressure.
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Im running it on normal diesel, only fuel that went through this pump was BP diesel. Im guessing it was a ****ty pump then, lets order another and see what happens...
 
How far was your drive home? Could be an airlock but would normally expect to see that immediately after fitting a new pump.
 
RichM said:
How far was your drive home? Could be an airlock but would normally expect to see that immediately after fitting a new pump.
Click to expand...

about 15 miles home, was fine at first and it all bleed out OK, was a bit ****ty when I got home so this morning I bleed it again before work. When I got here it was doing what it done before and not idleing. I took off the pipe to the filter and tried to prime it and nothing, took the pump off and theres no pumping action when pressing the mechanical lever, wont bleed or anything...

As long as theres not something im missing that will constantly destroy pumps then im gonna just refit another one, hopefullly it was just a bad one, cheers for the advice though
 
its common for lift pumps to fail often as yours has where the lever mechanism breaks ,often failure isnt noticed if system is very good and as injection pump will suck it through .the two one way valves often get **** sticking them open
 
jamesmartin said:
its common for lift pumps to fail often as yours has where the lever mechanism breaks ,often failure isnt noticed if system is very good and as injection pump will suck it through .the two one way valves often get **** sticking them open
Click to expand...
v

Is there any way of unblocking the valves?
 
there made of cheap **** so unlikely they would be any good ,the earlier ones like on series you could unscrew and fit new valves and diaphragm
 
Jongould said:
I got me a disco at the weekend with a suspect lift pump fault, I checked it out and yep, nothing from the pump so I bought it and when I got it home I changed it, the old one was kaput and the new one was all good, worked fine, primed up e.t.c. and ran beautifully for the drive home. Today it started doing the same thing as before and when I have looked into it its the lift pump again!!

Now am I unlucky with this one? It was a Fuelparts pump, is it best to go genuine? Or is there something else that can cause the to fail this quick?

Cheers

Jon
Click to expand...

Those lift pumps are one of the car's many Achilles Heels. I hate them. I had a 300 TDi Discovery running badly, jerking and running as if the engine had a misfire. Google said "Sedimenter Bowl" so I did that. After removing the rotten egg yolk, water and grit it was hoped that things would get better. They didn't! Now the engine would only run on the fuel that was in the filter and quit when the filter was empty. It was discovered that the Delphi lift pump would blow but not suck. A new pump was ordered. This seemed OK and a little test drive was taken. The bad running was however still present. A bad injector was suspected so all were pulled and taken to a tractor repairers where they still have a Lucas-CAV test room! All injectors were popping at about a ton per square inch, spraying nicely and not dribbling. Duh! The new lift pump is now not pumping after less than ten miles so it looks like a case of infantile failure. Next possibility it that the engine valves have become too tight (no hydraulic tappets on these unfortunately) Good job the Discovery is not my main car.

These pumps are so awful that it might be worth fitting an electric pump as used on mini diggers.
 
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Davey1000 said:
Those lift pumps are one of the car's many Achilles Heels. I hate them. I had a 300 TDi Discovery running badly, jerking and running as if the engine had a misfire. Google said "Sedimenter Bowl" so I did that. After removing the rotten egg yolk, water and grit it was hoped that things would get better. They didn't! Now the engine would only run on the fuel that was in the filter and quit when the filter was empty. It was discovered that the Delphi lift pump would blow but not suck. A new pump was ordered. This seemed OK and a little test drive was taken. The bad running was however still present. A bad injector was suspected so all were pulled and taken to a tractor repairers where they still have a Lucas-CAV test room! All injectors were popping at about a ton per square inch, spraying nicely and not dribbling. Duh! The new lift pump is now not pumping after less than ten miles so it looks like a case of infantile failure. Next possibility it that the engine valves have become too tight (no hydraulic tappets on these unfortunately) Good job the Discovery is not my main car.

These pumps are so awful that it might be worth fitting an electric pump as used on mini diggers.
Click to expand...



Sorry mate but I don't agree with your comments about Discovery lift pumps at all.

These cars runs for years and years on the original lift pump with no problems at all. However, once it comes to a DIY-er changing the pump for a new one it is not at all unusual to hear that they don't work and/or they are blowing not sucking.

This is caused solely by poor installation. It's very simple, two pipes, get them right and all is bliss. Get them wrong and you're shoulder high in ****.


Dave
 
15 miles, eeh luxury!

My new lift pump knackered itself in less than three. The pump was new and was bought on eBay. Prior to my little test drive the hand lever would produce strong spurts of fuel from the fuel filter and the engine ticked over OK. On the return journey of my little test drive the kangaroo effect returned so as the pump was new the injectors were suspected. Nope, the injectors were perfect, its that infernal pump again.
 
thebiglad said:
Sorry mate but I don't agree with your comments about Discovery lift pumps at all.

These cars runs for years and years on the original lift pump with no problems at all. However, once it comes to a DIY-er changing the pump for a new one it is not at all unusual to hear that they don't work and/or they are blowing not sucking.

This is caused solely by poor installation. It's very simple, two pipes, get them right and all is bliss. Get them wrong and you're shoulder high in ****.


Dave
Click to expand...

I think we know about the pipes mate. There is even a little arrow that shows which port is the input.

No the simple fact is that there are loads and loads of defective pattern-part pumps out there which are basically worthless. For instance when the hand lever produces strong spurts of fuel from the fuel filter one can presume that the pump is on the right way round. Also as these pumps don't use Tufnol spacer blocks it cannot be that. The pumps are junk and if I was to win the lottery big time there is NO WAY that I would buy a Land Rover as I've just about had a gutful.

Personally I prefer the Vancelli-Martelli (VM) engines although admittedly in the Range Rover and Discovery there used to be cooling problems. This was not the engines fault it was bad plumbing and the fact that the VM is much taller than the petrol V8. It is essential to get the coolant reservoir as high as possible with the VM. As to the VM lift pumps I have NEVER needed to mess with one. This over several Rover 800 2.5 turbo diesels and an ill fated VM Range Rover conversion (not done by me)

Anyone got a good Toyota Landcruiser going cheap?
 
thebiglad said:
Sorry mate but I don't agree with your comments about Discovery lift pumps at all.

These cars runs for years and years on the original lift pump with no problems at all. However, once it comes to a DIY-er changing the pump for a new one it is not at all unusual to hear that they don't work and/or they are blowing not sucking.

This is caused solely by poor installation. It's very simple, two pipes, get them right and all is bliss. Get them wrong and you're shoulder high in ****.


Dave
Click to expand...

My test on the Delphi pump was done OFF THE ENGINE. Although it is slightly yucky one can place ones tongue over each port in turn and operate the lever that is driven by the camshaft. When this was done it was found that the output port would blow but the input port would not suck so in my honest opinion the pump was defective. Is anyone going to contradict me on this?

The same test on the new pump proved that it would both blow and suck and it did indeed work OK on the engine for about two miles (that's a pump cost of about £7.50 per mile) After a couple of miles the kangaroo effect was back so it looks as if the pump is scrap. "Sealed for life" is just a catchpenny.
 
Seems that the problems I am currently having can be down to a knackered pump and gunged up sediment bowl but after reading the horror stories here re; dodgy pumps I was wondering if there is anything on the forum re fitting an electric pump?
 
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