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[richardoverend]

Hi all
first time posting but i find the forums so usefull.
I've had the jeep for 2.5 years originally with 90k now 124k.
signs of the black death on number 5 and recently on 1 and 3 as well so i stripped them all out replaced a cracked nozzle cap and refitted all with new seals and stretch bolts.
started up and after a ropy 2 minutes was running sweet as infact better than ever. drove around for 2 days with no problems apart from the usual severe cranking before she would go.
the Mrs then goes to the local supermarket and cannot start it. AA attended and for a change didn't really try (previous experience of the AA always excellent) so she was recovered back to my yard.
he told me that he had checked the voltage on the 2nd pin of the common rail pressure sensor and the voltage did not change above .5 v and he said should go to 5v if the pressure is good. the only code showing is 340 (cam position) with no MIL so i removed it and cleaned all and replaced but i think it is an old code from the sensor being unplugged during repair as it wont clear for 50 good cycles.
no other codes. have sprayed gt85 in and will fire easily but wont run. have replaced glow plugs in November with good volts to all. i had not primed the diesel as when  i changed the fuel filter 3 months ago cranking primed the fuel but i primed it yesterday by connecting a suction pump to the bleed valve and noticed a lot of air coming out which stopped after approx 1 ltr fuel. fuel is going to all five injectors but is not coming out of the returns on the top of the injectors. all this makes me think its the fuel pump but cannot understand why it would just fail at this time.
if the fuel pump was on its way out would this cause the starting problems i was having in cold weather?
does anyone know what the resistance values are across the rail pressure sensor?
if there was a lack of pressure would this normally show a obd code?
any other ideas or is it a case of removing the hp pump and servicing it?

[isle of man]

Have you used a OE filter???

[Dutch]

Hi Rich,

Sorry to hear the ol' WJ CRD is giving you a headache.  The tech. dept will be along soon.

Welcome   

[Mike Pavelin]

The pumps aren't a servicable item, you throw them away and get a new one.

[richardoverend]

Have you used a OE filter???

Yes i used the OE filter and even tried  another incase it was contaminated from the work.
i have read on a forum that someone had a similar problem and changed the 4 orings as theirs was drawing in air when the engine cooled down after starting and possibly this would cause a lack of pressure to the rail which (from what i have read) will stop the ecu from opening the injectors, so i will change the orings tomorrow and update the results. My only reservation is that there is no fuel leaking from around the pump which makes me think it is internal and therefore a new pump.
i was puzzled at the fact that while cranking there was no fuel coming out of any of the injector returns and can only pressume that this is because the returns will only open when there is enough pressure in the injector.
thanks for the replies so far

(Edit by tim to fix quoting)

[daggie]

I had this on a mates crd at xmas, same probs
you need to get it to someone who has the bosch engine controler diagnostic tool
they prime the diesel system using their magic box 

it could be the fuel pressure regulator, situated on the back of the hp diesel rail, the O rings split its also a twat of a job

[richardoverend]

I had this on a mates crd at xmas, same probs
you need to get it to someone who has the bosch engine controler diagnostic tool
they prime the diesel system using their magic box  

it could be the fuel pressure regulator, situated on the back of the hp diesel rail, the O rings split its also a twat of a job

i think you might be right. this was also suggested by a friend today and even more annoying it was easy to get to when i dropped the engine to do the injectors. i can get to the bolts but do you know how far it goes into the rail so i can work out whether there is enough room to slide it out of the rail?

i stripped the lp and hp pumps today, nothing really to go wrong with the lp apart from the commection o rings but i have ordered an overhaul kit for the hp which was £27 plus the dreaded. quite straight forward to strip and service but was trained in hydraulics many moons ago. the only worrying thing was the lack of diesel in there considering i had bled the system with a suction pump so i suspect it was just airlocked.
the parts will be here tomorrow and i will try it before attempting the solenoid valve.
i was told that when the o ring on the solenoid valve splits it allows fuel to bypass before it reaches pressure which would explain the injectors not bleeding off, just seems too much of a coincidence for it to go at that time.


(edit by tim to fix quoting)

[richardoverend]

 
success!
overhauled the high pressure pump and refitted it and still no diesel on the high pressure side so i removed one of the heads and filled the pump up with diesel turning it to fill all the chambers. refitted it and all is well running better than ever and very smooth so really pleased.
pump was quite easy to do but you have to watch the tiny NRVs. thanks to all for advice given.
i also checked the pressure regulator for orings and gave that a clean as well. quite easy to remove using a 1/4 inch ring spanner as there's no room to get a socket in there.