Help 3.5 EFI wont start

I am about to give up. I have just finished changing the bearings and the head gaskets. And now it wont start. I have a new distributor. Checked all the earths, I definitely get a spark at the plugs. The fuel pump works very well.
The spark plugs smell like they are getting fuel but not soaked. It does turn over as well as I just re conditioned the starter motor. I'm running out of ideas.
The only thing I can think of is the fuel shut off relay. I don't hear it click. Also when I got the engine there were no vacuum pipes attached so I think i've got them right but I'm not sure, would this have an effect?

Thanks in advance

David

ps tested the resistor pack and it looks like it works

Bit of a minefield in my view mate.

Have you checked compression?

Timings?

Yes and yes.

I've tried everything. I've just been told to double check the earth on the fuels shut off so I'll try that tomorrow.

Dave

the fuel cut off is vac operated. make sure it's connected properly. if not you'll get fuel on cranking but pump won't run.

Your right the fuel pump isn't running on cranking. I'm just about to go have a look and see what i can do.

Thanks

I'll let you know how I get on

Dave

is it a flapper or hot wire?

It's a flapper. I have a new one coming, This one works but is really stiff. It just back fired after a few seconds of cranking so I'll double check the timing after I've fixed the starter motor again

David

Update;

After fixing the starter motor, sealing all the vacuum pipes, cleaning all the earths and adding a few in for good measure.

It started for all of 5 seconds and cut out.

at least it's something

thats good. shows pump is working when cranking. sounds like it's not getting power from ecu to pump. needs signal from vac switch and feed from coil via ecu for pump to run after cranking and starting.. you should get 12volts to pump when cranking(direct feed) then ecu takes over. check voltage at pump feed when cranking, if it drops to zero on release of key, this where you need to be looking. flap should move easily and spring back.

is it in a rrc or a transplant?

maybe run a temporary feed to the fuel pump, thats gets you your fuel pressure - get it running and sort any other issues out, get it dried out and running clean, and then try again to solve your issue.

at least that way you know it will start when it should.

cheers

he's getting pressure, else it wunt start.

alright not just pressure, but constant pressure, so that it'll run!

Right it is a rrc engine that has been put into a defender with a LPG conversion. I took it off a friend who had it sitting in a field and it hadn't been running for 3 years after a head gasket went.

I was shocked to see no one had put an inertia switch in though after spending hours tracing all the wiring.

I'm sorry for my ignorance on the V8s I've grown up around diesel land rovers.

I'll check the voltage tomorrow to the pump from the ecu. Am i right in thinking it's the red and blue wire that goes through the extra air valve then becomes white and purple?

Sorry for my ignorance. This is my first engine rebuild.

I had thought about running the fuel pump straight from the ignition but I thought the problem was with the injectors and ecu.

Thanks so far.

Dave

Mr Noisy said:

alright not just pressure, but constant pressure, so that it'll run!

Click to expand...

haven't i just said that?

Thanks for all your help
I got it started half an hour ago. I ran a new earth from the ecu and that fixed it.

The next problem is that it wont rev. Now I know the air flow meter wont allow it to but I've got it going on gas. So the afm shouldn't matter. I've had the timing light to it. And the throttle potentiometer be needed either.

Any ideas?

Thanks

if it is bogging down on opening throttle on gas I would suspect distributor advance weights, incorrect timing.

you said it backfired earlier, was it though the plenum?

3.5 efi said:

you said it backfired earlier, was it though the plenum?

Click to expand...

Yes

theres an 'anti blow back flap' in the gas metering head. have seen one where a blow back had forced it past its seat and had wedged it in the body, restricting air flow. similar symptoms as you describe due to lack of air.

:doh: after spending a while playing around the LPG system isn't working as I flicked the switch and disconnected the fuel pump and the engine died soon after.

The afm should come tomorrow so i'll get the petrol running and i'll then start on the LPG.

Thanks for all your help

Dave