Broken down. Any ideas?

Just broken down on the way to work. I'm almost sure it's fuel related. Been running on bio diesel for the last 600 miles in my discovery 300tdi. Cleaned sedimenter out last week and have been carrying spare fuel filter in the car. I was going along fine about 55 mph, when it just started to slow down. Revs just seemed to die, then it started jerking. Managed to get somewhere to have a loom by creeping along and keeping the revs under 1500.

Changed fuel filter. Made no difference. It started and ticked over, but wouldn't rev. No air/fuel was coming out of the bleed screw, which i had loosened, on top if the filter housing. Thought the sedimenter must be choked, so got under there and had a look. It was still spotless from last weeks clean out. I'm knackered now and just waiting for RAC. I'm thinking it might be the lift pump, but do they go as suddenly as this seems to have done? It did struggle to start this morning.

I'd be very grateful for any advice. Thanks.

theres a second filter near the back, sometimes bypassed but if its still there it could be the culprit if not lift possibly as you say

Any idea where this second filter is? Are you talking about the sedimenter? I've had that off twice now and it isn't that.

Yep thats the one, sounds like lift then as its obviously getting enough fuel to run but not under any form of load

Just ordered a new lift pump. Hope that's all it is.

Hopefully it is too, cant really think of any other reason

Sedimentor clean
New fuel filter
300tdi is auto bleed
Gets enough fuel to start and tick over


Logic would lead you to look towards the lift then

it should run with out a second lift pump,

Dr_evil said:

Hopefully it is too, cant really think of any other reason
300tdi is auto bleed

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There is a bleed screw for the lift pump, well, its on the filter housing...


What happens when you bleed it via the fuel filter housing? Does it come out nice and clear or a bit frothy? If its the later the sedimenter has gone porous, bypass it, if the bleed screw is all clear diesel then move onto the lift pump next, undo the outlet and crank over, make sure its a nice consistant squirt from it, if not replace it with a delphi one. Next crack of injector pipes, be carefull though as they are high pressure, is there fuel here? If so then your fueling side looks OK, if not it could be pump or injector pipes (if the other checks looked OK)

could be a blockage in the fuel line , try blowing air back down from the engine bay fuel filter to the sedimenter and from the sedimenter to the tank... someone listening by the open fuel filler should be able to hear air bubbling up through the fuel.
.

Yep even if the lift pump is knackered the injection pump will pull it through from the tank, sounds like you have got air in the fuel lines. Check the fuel elbows under the boot carpet

DEFENDER90-DAZ said:

Yep even if the lift pump is knackered the injection pump will pull it through from the tank, sounds like you have got air in the fuel lines. Check the fuel elbows under the boot carpet

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Injection pump will pull through to an extent though cos its running just might not be enough to get it to power it when it needs loading

Might as well change it anyway if its still the original, I've had mine done when the cam belt was.

hole in the fuel line though would have thought he'd be able to smell a bit once standing if it was big enough to let enough air in to stop it running ?



In theory as its an autobleed pump would it not also judder as bursts of air shoot through with the fuel ?

The elbows under the boot carpet are notorious for allowing air into the fuel lines - you will know if its the lift pump as it won't allow the engine to rev over 2500 rpm and will make it sluggish on hills. The elbows in the boot are the fuel pickup/return lines and are covered with a metal plate - so unless you check them you don't really smell any fuel.

DEFENDER90-DAZ said:

The elbows under the boot carpet are notorious for allowing air into the fuel lines - you will know if its the lift pump as it won't allow the engine to rev over 2500 rpm and will make it sluggish on hills. The elbows in the boot are the fuel pickup/return lines and are covered with a metal plate - so unless you check them you don't really smell any fuel.

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depends if he still has a boot floor or not though

Jongould said:

There is a bleed screw for the lift pump, well, its on the filter housing...


What happens when you bleed it via the fuel filter housing? Does it come out nice and clear or a bit frothy? If its the later the sedimenter has gone porous, bypass it, if the bleed screw is all clear diesel then move onto the lift pump next, undo the outlet and crank over, make sure its a nice consistant squirt from it, if not replace it with a delphi one. Next crack of injector pipes, be carefull though as they are high pressure, is there fuel here? If so then your fueling side looks OK, if not it could be pump or injector pipes (if the other checks looked OK)

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lift pump can cause air at the filter

DEFENDER90-DAZ said:

Yep even if the lift pump is knackered the injection pump will pull it through from the tank, sounds like you have got air in the fuel lines. Check the fuel elbows under the boot carpet

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it wont but will if systems full as in running fine then pump fails

jamesmartin said:

lift pump can cause air at the filter

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'tis very true, I would normally expect a clearish flow though unless the lift pump is seriously leaking air into the system and even then I would have expected to have a lack of flow as opposed to airated fuel

As the ip uses fuel it will draw it from the filter and through the lines from the tank, if the diaphragm in the lift pump has gone then yes the air will be introduced there.

classic advise there , start boltin on new bits without checking the basics of blocked or punctured fuel lines
funny how a guy with close on 3k posts about not bein able to start his engine thinks hes got good advise to give to someone else.... specially when he dont seem to know the difference tween a sedimenter and a filter....

ricc said:

classic advise there , start boltin on new bits without checking the basics of blocked or punctured fuel lines
funny how a guy with close on 3k posts about not bein able to start his enginegoing thinks hes got good advise to give to someone else.... specially when he dont seem to know the difference tween a sedimenter and a filter....

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Couldn't be arsed typing it out…..its still a kind of filter anyway isn't it you troll :doh: anything that removes sediment, water etc is a filter :doh:




Because what does a sedimenter do ?

It collects water and the larger bits of grub that come out of the tank :doh: exactly like that a _ _ _ _ _ _ does ?

i agree with ricc happened to me yesterday you need to blow the fuel lines threw and check the filter on your lift pump if you have a delphi one should be fine oh and make sure you take fuel filler cap off first before you blow threw the lines.