Problems starting p38 diesel

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On mine you needed a lot more than 1\4 tank to solve the in tank stupid broken pump union thing.
We also fitted a one way valve in the fuel line but it did not help
We have a spare new in tank pump in Somerset if you want to try it and I have the floor cutting dimensions some where

First get some clear tube in the fuel line then you can see whats going on
 
blackburnbertie said:
Didn't do the job. Back to square one. There's plenty of fuel getting through once it's going. Everywhere is bone dry apart from pot no1 hence the off injector lines change. I wouldn't of thought it was the fuel heater but I'll get new seals slapped in the fuel in and out lines. Can't understand why people think it's the intank pump. The tank is rarely below a quarter full. Any thoughts?
Click to expand...

The FIP needs a good supply of fuel to work properly. In the Techincal Section (or How To) there is a post by Wammers saying how to check the in-tank pump. Easily done which is why it is a quick one to rule out at the start. In short you disconnect the fuel line somewhere easy, bridge the fuel relay and see how much squirts out in a given period of time. Wammers will probably disagree but the Bosch book I read said the FIP needs a minimum pressure to work properly.

The business with the tank at least 1/3rd full is a differrent problem.

@tarphenry is near you (Bury). I cannot remember if he has a Nanocom or not but might be worth a PM and see if he has. Failing that check the Landyzone International Map.
 
markemark said:
On mine you needed a lot more than 1\4 tank to solve the in tank stupid broken pump union thing.
We also fitted a one way valve in the fuel line but it did not help
We have a spare new in tank pump in Somerset if you want to try it and I have the floor cutting dimensions some where

First get some clear tube in the fuel line then you can see whats going on
Click to expand...

Fuel line from filter to FIP should be clear anyway. Might need cleaning with some spirit.
 
markemark said:
On mine you needed a lot more than 1\4 tank to solve the in tank stupid broken pump union thing.
We also fitted a one way valve in the fuel line but it did not help
We have a spare new in tank pump in Somerset if you want to try it and I have the floor cutting dimensions some where

First get some clear tube in the fuel line then you can see whats going on
Click to expand...
The dimensions would be great. Save me pulling the tank out. So what we are saying in the in tank pump may be screwed. I'll get it over to my mates Monday.
 
blackburnbertie said:
The dimensions would be great. Save me pulling the tank out. So what we are saying in the in tank pump may be screwed. I'll get it over to my mates Monday.
Click to expand...
Another thing which may have nothing to to with this but my fuel tank reading on the dash is all over the place. I can put 50 notes in but the needle sometimes sticks on say a quarter. Ten mins later it'll shoot up to what it should be. Just thought I'd mention it.
 
wammers said:
The pump and it's mesh inlet are within 10 mm of the bottom of the tank. Fuel can leak out under pressure if the pipe from pump to top of unit is cracked but it cannot suck air unless the tank is completely empty, a pressurised line cannot suck air, it is not possible. If the lift pump is not working the injector pump can suck air past the filter O'rings. Genuine lift pumps have an NRV in them which makes this more likely if they have failed.
Click to expand...
That makes sense. So what you're saying that once I've got the car running the high pressure pump on the engine draws through the fuel from the tank via the filter head and those seals on either side of the head are not under pressure and can therefore let in air ?
 
blackburnbertie said:
That makes sense. So what you're saying that once I've got the car running the high pressure pump on the engine draws through the fuel from the tank via the filter head and those seals on either side of the head are not under pressure and can therefore let in air ?
Click to expand...

If the in tank pump is duff fuel has to be drawn past it, so flow is restricted, it is a lot easier to draw air in past the o'rings than it is to blow fuel out, because as you say the pressure seals them when the in tank pump is running. Normally with the in tank pump duff the car will start and run without issue around town but you will notice lack of power on hills.
 
Grrrrrr said:
The FIP needs a good supply of fuel to work properly. In the Techincal Section (or How To) there is a post by Wammers saying how to check the in-tank pump. Easily done which is why it is a quick one to rule out at the start. In short you disconnect the fuel line somewhere easy, bridge the fuel relay and see how much squirts out in a given period of time. Wammers will probably disagree but the Bosch book I read said the FIP needs a minimum pressure to work properly.

The business with the tank at least 1/3rd full is a differrent problem.

@tarphenry is near you (Bury). I cannot remember if he has a Nanocom or not but might be worth a PM and see if he has. Failing that check the Landyzone International Map.
Click to expand...

When the engine has been stopped a while there is no pressure in the injection pump. It bleeds off through the return. There is no pressure in the pump for cold starts, other than the small amount from the lift pump. Which aids fuel flow through the injection piston feed port. For cold starts extra fuel is set and glows are active bringing on the lift pump. Pressure has bled away, putting the timing device in a static advanced state. People with an hot start problem will notice that if the car is stopped then started again before internal pressure bleeds off, usually the car starts no problem. It is only when the pressure has bled off and the engine is too hot for glows that there is a problem with starts, causing long cranking. Land rover or more precisely BMW tried to overcome this from MY 1999 by bringing lift pump on with cranking. Before that lift pump was only on with glows and when engine was running. Starting with a duff lift pump is certainly better if the tank has plenty of fuel in it. Owners may not even notice any problem most of the time, other than a lack of power on hills. Normal internal pressure with engine running is between 3.5 and 4.5 bars dependent on RPM. This internal pressure is controlled by a relief valve and supplies a pre-injection pressure and is also used to adjust the timing device via the timing modulation solenoid. To maintain an injection point around TDC. :)
 
Last edited:
blackburnbertie said:
The dimensions would be great. Save me pulling the tank out. So what we are saying in the in tank pump may be screwed. I'll get it over to my mates Monday.
Click to expand...

Dimension correct, we used it...........obviously you will end up using a grinder because nothing else around.........DON'T cut deep as pipes, wires and tank
We bodged the original boot floor back in after, gaffer and gunk, big covering plate, carpet and beer.........no welding )) you know why ))
If you cut pipe go to hydraulic hose repair shop and buy a funky bodge part, take a bit of fuel pipe as 100's choices

The pump has at least 2 issues......... !) old dead plastic cracking up, 2) motor not pumping enough liter per min.............lots of tests here or maybe just a knackered motor with brush issue

We used this info below
http://www.rangerovers.net/repairdetails/fuelpump.html


range rover fuel pump.jpg
 
markemark said:
Dimension correct, we used it...........obviously you will end up using a grinder because nothing else around.........DON'T cut deep as pipes, wires and tank
We bodged the original boot floor back in after, gaffer and gunk, big covering plate, carpet and beer.........no welding )) you know why ))
If you cut pipe go to hydraulic hose repair shop and buy a funky bodge part, take a bit of fuel pipe as 100's choices

The pump has at least 2 issues......... !) old dead plastic cracking up, 2) motor not pumping enough liter per min.............lots of tests here or maybe just a knackered motor with brush issue

We used this info below
http://www.rangerovers.net/repairdetails/fuelpump.html


View attachment 116175
Click to expand...
Cheers mate.its worth a serious consideration. Fresh plate on top riveted would do I suppose.
 
yes but diesel is hard to set on fire.........we try on our Kaliningrad Russian farm here very hard with stick welders....plastic tank.....holes......not good
Apparantly tank comes out easy but I did not have the ramp free or the effort free
Yes just pop rivet a bodge down and put gunk on it plus then bigger cover plate

We did all this and there were several issues with heater plugs, FIP, injectors, tank pump, control injector, fuel filter sensor.......its not amazing now but it does run well

The only thing left now is to re-time static FIP for stretched chain with dial gauge and locking tools etc
 
dont cut a whole in it! Find a way with borrowed ramps and a good car jack. It's a longer job this way round but you'll have an intact floor and no smell of grinder dust in the car. Jesus guys!!
 
Mark Piercy said:
dont cut a whole in it! Find a way with borrowed ramps and a good car jack. It's a longer job this way round but you'll have an intact floor and no smell of grinder dust in the car. Jesus guys!!
Click to expand...
Our car is a farm work vehicle with Dogs, cartridges, mud, paper work, young children things, oil, farm spares, tools etc. Yes your correct if its a wedding car but to us it was more important to harvest 30,000 ha of arable crop not spend that time under the car...............depends whats going on
Remember because its your view it does not mean its relevant to others ))
 
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