Does diesel return valve do anything?

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Evan farmer

Active Member
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782
i ordered air bleed valve and return and gaskets for the regulator to try and gain 0.5 bar of pressure as mine has 3.5 bar and the rest of my gaskets arrives before the return so is it worth waiting for it? Or is it useless
 
i ordered air bleed valve and return and gaskets for the regulator to try and gain 0.5 bar of pressure as mine has 3.5 bar and the rest of my gaskets arrives before the return so is it worth waiting for it? Or is it useless
why dont you try and remove the air bleed and none return then test pressures instead of waiting or before purchasing
back a few year ago i tested mine i removed the air bleed valve and none return valve i had no ill side affects to be honest i cant even remember if i re installed them

where about did you order the none return valve i got told by my local landrover that this can not be purchased on its own and that a hole new filter housing is needed this was a few years ago

as for gaining pressure could be a few other things like fuel filter /fuel pump/ or the regulator is slightly by passing or the gauze filter inside the cylinder head where abouts are you reading fuel pressure

do you have any abnormal sounds when the fuel pump is running ?

ps do you notice that you may have higher fuel pressure on a cold engine to a warmed up engine ? take note of fuel return temps is the fuel fuel filter getting hot hot due to a bad or failed thermostat located inside the fuel cooler... if so this may of weakened the fuel pump or regulator over time
 
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Just the black part of the return valve the fuel pump doesn’t shut up only after about 5mins but still doesn’t start after that before changing regulator as I had a fuel leak and sounded like air was escaping no fuel leak or air being lost there now but you can hear it being squirting about in the regulator I changed fuel filter as well
 
Just the black part of the return valve the fuel pump doesn’t shut up only after about 5mins but still doesn’t start after that before changing regulator as I had a fuel leak and sounded like air was escaping no fuel leak or air being lost there now but you can hear it being squirting about in the regulator I changed fuel filter as well
it might take a little time for the air to fully escape since you have had the fuel system opened up i normally take mine for a run other wise i purge it many times

as for the slight pressure drop this depends on how your measuring is the slight pressure drop more while coming on boost ie fuel demand... or is this pressure drop les the same when engine is just idling if so yes posibble one of the stages is failing in side the pump

also when you renewed the regulator did you clean the gauze in side the cylinder head also there should of been a small oring

ps where did you purchase your regualtor i also got told from landrover to stay away from the ones on the net as they noticed they also had issues apparently the same fuel pressure regulator is used on some VW engines that run slightly different pressure.... unsure what i got told is true as i had many issues with them in the past... basically there words was they are the same but not the same but then they go on to say if i want one we will have to order it in probly on the net

is your fuel pump making any weird noises like screaming ?
 
it might take a little time for the air to fully escape since you have had the fuel system opened up i normally take mine for a run other wise i purge it many times

as for the slight pressure drop this depends on how your measuring is the slight pressure drop more while coming on boost ie fuel demand... or is this pressure drop les the same when engine is just idling if so yes posibble one of the stages is failing in side the pump

also when you renewed the regulator did you clean the gauze in side the cylinder head also there should of been a small oring

ps where did you purchase your regualtor i also got told from landrover to stay away from the ones on the net as they noticed they also had issues apparently the same fuel pressure regulator is used on some VW engines that run slightly different pressure.... unsure what i got told is true as i had many issues with them in the past... basically there words was they are the same but not the same but then they go on to say if i want one we will have to order it in probly on the net

is your fuel pump making any weird noises like screaming ?
The pump is screaming for about 5 mins then stops it doesn’t start that’s the problem
 
The pump is screaming for about 5 mins then stops it doesn’t start that’s the problem
fuel pump start back up ? or the engine doesnt start ?
if its screaming like a cat also means air in the system still .....does the engine start and run ?
 
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its hard to say without replacing the fuel pump but you might want to measure cylinder head fuel pressure

also check your engine oil level incase there isnt a injector oring leaking
 
its hard to say without replacing the fuel pump but you might want to measure cylinder head fuel pressure

also check your engine oil level incase there isnt a injector oring leaking
No extra oil but the injectors haven’t been coded so might be a reason so either getting a mechanic with the right software to code them or swapping them with old engine
 
No extra oil but the injectors haven’t been coded so might be a reason so either getting a mechanic with the right software to code them or swapping them with old engine
there was no mention about injectors being swapped out nor an old engine
did the engine engine start and run before the injector swap ? and are they plugged in ? sorry i had as my self can get easily side tracked also what do you mean old engine ? has this engine just been replaced ?

the fuel priming sequence doesnt actually prime the injectors if there is an air lock inside the injector or injectors this may take some time to to remove while cranking slower like using the starter motor
if your fuel pump is still screaming could be knackered like you said or air still in the system

i once ran out fuel as my fuel gauge arm was not accurate as i must of bent it slightly when cleaning the fuel tank out ..i added fuel and primed many many times still not start ..i sprayed some some deodorant that i had laying in the glove box down the air intake to help and to give the starter motor a bit of a break ..... engine fired up and ran on its own fuel supply
 
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there was no mention about injectors being swapped out nor an old engine
did the engine engine start and run before the injector swap ? and are they plugged in ? sorry i had as my self can get easily side tracked also what do you mean old engine ? has this engine just been replaced ?

the fuel priming sequence doesnt actually prime the injectors if there is an air lock inside the injector or injectors this may take some time to to remove while cranking slower like using the starter motor
if your fuel pump is still screaming could be knackered like you said or air still in the system

i once ran out fuel as my fuel gauge arm was not accurate as i must of bent it slightly when cleaning the fuel tank out ..i added fuel and primed many many times still not start ..i sprayed some some deodorant that i had laying in the glove box down the air intake to help and to give the starter motor a bit of a break ..... engine fired up and ran on its own fuel supply
The original engine cracked the block so I bought a disco 10p with a cracker of an engine I swapped the ecu so the defender had a discovery ecu in it and the engine light flashed whilst pumping throttle and stops after a few seconds 20-30 and then starts again in about 5 seconds so air must be getting in in the copper washers in the fuel filter housing
 
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