Hello All.
I have a problem with my 96 300TDI... Its been running fine for months but 2 days ago I came to start her up and I had to crank the motor for a lot longer than normal. When she fired up everything was normal, I expected clouds of smoke from over fuelling but no just its usual morning chuff,, after a short run I stopped switch off then after maybe 5 seconds hit the starter and she fire first turn,,,,,,, It seems to me like fuel is syphoning or draining away from the injectors and I have to wait for the L/P to push it back,,,,,, Im thinking I have a shot lift pump or vacuum in the tank,,,,,,, Anyone got a better idea.
Thanks All.
Tom
 
Hello All.
I have a problem with my 96 300TDI... Its been running fine for months but 2 days ago I came to start her up and I had to crank the motor for a lot longer than normal. When she fired up everything was normal, I expected clouds of smoke from over fuelling but no just its usual morning chuff,, after a short run I stopped switch off then after maybe 5 seconds hit the starter and she fire first turn,,,,,,, It seems to me like fuel is syphoning or draining away from the injectors and I have to wait for the L/P to push it back,,,,,, Im thinking I have a shot lift pump or vacuum in the tank,,,,,,, Anyone got a better idea.
Thanks All.
Tom

Cracked fuel pipe allowing air in.
 
Check the leak back pipes before the rest, but a piece of clear tube will help locate it.
This one, The leak off pipes between the injectors will be the most likely culprit to have aged and become porous allowing fuel to drain back. Very easy to change, just press fit 8mm (from memory) fuel pipe over the injector pipe. I end up replacing mine every couple of years but it is a 10 min job and nice and cheap to swap over and see if it solves the issue.
 
Thanks All
Im fairly sure its the L/P... took it for a short run,,,, ticks over fine and drives on low revs ok, but put your foot down it starts to die and splutter,,, foot off and it comes back to normal tickover,,,,,, pump cant keep up with demand.... but a chance to check all the pipes while im changing the pump
 
Thanks All
Im fairly sure its the L/P... took it for a short run,,,, ticks over fine and drives on low revs ok, but put your foot down it starts to die and splutter,,, foot off and it comes back to normal tickover,,,,,, pump cant keep up with demand.... but a chance to check all the pipes while im changing the pump
Could be, I'd also look for an air leak. Could be a union, cracked fuel line or even a loose filter.
 
Thanks All
Im fairly sure its the L/P... took it for a short run,,,, ticks over fine and drives on low revs ok, but put your foot down it starts to die and splutter,,, foot off and it comes back to normal tickover,,,,,, pump cant keep up with demand.... but a chance to check all the pipes while im changing the pump

By all means replace the LP, but let us know where the leak is after. I had the same symptoms last year, changed the LP as I had one on the shelf, still the same.
 
I would have said battery getting weak but as its not running properly now, I would start with filter first.
 
Right,,,, Ive got the pump off and checked the pipes with comp air in a bucket of water,,, no leaks found, unions ??? they seemed ok they were all dry and looked good I know looks can be deceptive,,,, the pump however had a very stretched and crap looking diaphragm, id say its gone porous. Time will tell when I have the new pump here..... yes could still be a leak but from what im looking at the pump diaphragm looks favourite at the moment.. tried the pump by hand with a finger over the unions,,, wasn't much uumph on either , but we wil see
 
I found the problem,,, the wee valves in the pump were full of crap , well whole thing was and very corroded , looks like I need a tank flush and an inline filter, it looks like theres been water stood in the pump for a while, With the lock down it hasn't been run for nearly 2 months ??? Oh well new pump arrives today.............. Im just wondering if I could fit some kind of water trap, could help a lot if I get more of this problem.
 
The storey so far.
Ive now changed the L/P, tank to pump pipe, pump to filter pipe, fuel filter and guess what,,,,,,,,, nowt,,,, its still the sme no fuel coming out of the filter bleed. Im at the point of trashing the pump and fitting an electric jobbie...... No I haven't changed the return pipes, no point the fuel isn't getting that far, it fire up on whats in the filer, which isn't much,,,, touch the throttle and its starts to die, then rough miss firing tick over till a little juice gets to the filter then it evens out................... I feel a V8 coming on
 
I was going to say spill pipes,fuel pick up pipe blocked/restricted, lift pump but as you have changed these I’m going to say go electric.
You can then pressurise the system to the HP pump to see if you may have a leak.
Good to see you have your motor back ;)
 
The storey so far.
Ive now changed the L/P, tank to pump pipe, pump to filter pipe, fuel filter and guess what,,,,,,,,, nowt,,,, its still the sme no fuel coming out of the filter bleed. Im at the point of trashing the pump and fitting an electric jobbie...... No I haven't changed the return pipes, no point the fuel isn't getting that far, it fire up on whats in the filer, which isn't much,,,, touch the throttle and its starts to die, then rough miss firing tick over till a little juice gets to the filter then it evens out................... I feel a V8 coming on

@border might be able to shed some light.

Personally, I would ditch the unions on the LP, push the fuel lines straight onto the steel pipes and use fuel clamps. I would also add a piece of clear pipe, probably between the LP and filter. Change the leak back pipes, for the few £ it is for a meter, it’s stupid not to.


Oh, and for the record, told you so. :p;)
 
I found the problem,,, the wee valves in the pump were full of crap , well whole thing was and very corroded , looks like I need a tank flush and an inline filter, it looks like theres been water stood in the pump for a while, With the lock down it hasn't been run for nearly 2 months ??? Oh well new pump arrives today.............. Im just wondering if I could fit some kind of water trap, could help a lot if I get more of this
 
The storey so far.
Ive now changed the L/P, tank to pump pipe, pump to filter pipe, fuel filter and guess what,,,,,,,,, nowt,,,, its still the sme no fuel coming out of the filter bleed. Im at the point of trashing the pump and fitting an electric jobbie...... No I haven't changed the return pipes, no point the fuel isn't getting that far, it fire up on whats in the filer, which isn't much,,,, touch the throttle and its starts to die, then rough miss firing tick over till a little juice gets to the filter then it evens out................... I feel a V8 coming on
is the pick up blocked,pipes the pumped pipes on right ,pump working
 
If this is your recovered motor Quick thought... was the HP pump solenoid damaged or tampered with to get it running?
 

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