Isuzu Trooper Owners Club UK™

GJones · ** Joined: 28 Apr 2012 Posts: 55 Location: Scotland

Hi,

My trooper takes a couple of good turns to start in the morning. If I pump the hand primer it starts right away. It's then fine for the rest of the day, up to about 8 hours. I replaced the fuel pipes from the tank back to the engine. However the problem still existed.

I have now replaced all the fuel pipes with clear ones at the engine end so I can see what's happening.

The question I have is: The the fuel pipe going in to the hand primer is solid diesel with no air, however the fuel pipe coming out of the hand primer and in to the engine is not solid diesel, it's more of a trickle half filling the pipe. Is this normal or should the fuel pipe be solid with diesel and no air in the pipe?

Regards

Gordon

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Browndoff · Posted: Sat May 10, 2014 21:09 Post subject:

Well done, Gordon! Good, logical approach to the problem.

YES - the outflow-pipe SHOULD be full of fuel - without air-bubbles. The fact that your clever mod has quickly shown up the problem [air leaking INTO the system at the Filter] may well have saved you hours of fruitless testing. If you strip it down and clean it thoroughly, you may succeed in fixing the leak - if NOT, you'll have to replace it with another Filter unit.

There's a little 10mm bolt-head sticking out of the body - specifically for bleeding AIR out of the system. This may not be seating properly and sealing the system. It would be suspect #1!
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2002 LWB Trooper 3.0L
I've done some major repairs, including replacing half-shaft, replacing fuel-injectors etc.

GJones · ** Joined: 28 Apr 2012 Posts: 55 Location: Scotland

Thanks, a few weeks ago I bypassed the hand primer with an inline one and it had air in it too? Which goes against logical thinking (fuel pipe in is solid fuel with no air). If you're saying it should be solid fuel in the line going in to engine (the out pipe) then that's a good start for me, will need to have a think about this. Clear fuel pipes do help as you said.
Regards Gordon.

Gribble · Posted: Sat May 10, 2014 22:23 Post subject:

Mr B ,you know there is a restrictor in the fuel outlet from the head so the . Tgfuel flow will be much less.
It keeps pressure round the injectors.

Gordon you may need something to stop the fuel drawing out the head overnight .
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Browndoff · Posted: Sun May 11, 2014 16:46 Post subject:

Dear Mr. Gribble - I fear that ONE of us - if not BOTH - is slightly confused here!

Gordon and I were talking ONLY about the inlet and outlet pipes on the fuel-filter itself - both of which should flow FULL of fuel.

YES, of course, the fuel-return-pipe [at the back of the cylinder-head] has a little restrictor in it [as you say] to maintain fuel-pressure in the head. It is also, clearly, true to say that if there's an air-leak in THAT area that it would drain the fuel from the head overnight and lead to difficulty achieving fuel-pressure to start the engine first-time.

But - whatever additional difficulties might later be found THERE [returning the fuel to the Tank] - he has already found air getting into the fuel-system before it even reaches the fuel-pump [down by the HP-Oil-Pump] - so, I'm inclined to think, we should concentrate on fixing THAT first............NO?
_________________
2002 LWB Trooper 3.0L
I've done some major repairs, including replacing half-shaft, replacing fuel-injectors etc.