Help needed please - fuel issues and starting problems

[mach2]

Gents,
Help required please.

So the car has been laid up over the winter while I've done a few refurb jobs on the suspension, etc.
Battery was disconnected and was on trickle charge throughout.

Go to start the car earlier but it won't start up.
Check the spark at the plugs and all 8 are good. Check the plugs and they are dry, no fuel getting into the bores.
Fuel pump is priming and providing fuel to the rail, checked this by removing the fuel feed at the rail and there is a plentiful supply of fuel coming through. However there is no fuel coming to the return side of the rail and when depressing the vent on the fuel rail nothing is coming out.
I'm at a loss as to why no fuel is getting to the bores when it's at the rail or why there is nothing in the return feed.
Have checked fuses, relays, etc but all are working.
What am I missing? All advice greatly appreciated.
Thanks guys

[mach2]

ianwayne said:

Sounds like you may have a blockage in the fuel rail.

If you press the little schrader valve on the o/s of the fuel rail after initial ignition on, do you get a spurt of fuel out? If so, you have fuel pressure in the rail. Unless that is what you meant by the vent.

Yes, sorry, my description wasn't the best but there is no fuel coming out of the Schrader valve. Whilst I understand the thinking behind the fuel blockage I just can't see how it would have occurred? The fuel system hasn't been apart. I have had the plenum off but everything has been re-connected.

[mach2]

Sardonicus said:

How can you have fuel to the rail but none at the schrader valve that cannot be ?

My thoughts exactly but that's what I'm faced with.
When I disconnected the fuel feed at the rail and primed the pump the fuel was flying out so
to me the fuel is getting through. When I reconnected the pipe, primed the pump again and depressed the
Schrader valve nothing came out. Somewhat bemused by it.
My only thought could be that the regulator is somehow constantly open in overflow mode and is venting the fuel before it's getting to the injectors. Would that make sense?

[mach2]

mark-tda4s said:

If youve had the plenum off, have you reconnected the vacuum pipe from the regulator valve to the plenum nipple under the stepper motor?

Yes, it's re-connected. Would this make a difference if it wasn't connected? I assumed that pipe was effectively the overflow to vent excess pressure from the regulator?

[mach2]

Thanks guys, I understand a bit more about the regulator now so will look at that in the first instance as it appears the fuel doesn't seem to be getting past this point. Pain in the arse though to change th thing.....

[mach2]

Steve_D said:

You have already disconnected the fuel feed and proved there is fuel flow there but I don't believe you have proven that there is pressure.
Next disconnect the return pipe and see if you have flow there.

Steve

Thanks Steve. I'm assuming if I have no flow at the return that the diaphragm isn't allowing the fuel to flow around the rail and its likely that the diaphragm is the culprit.

[mach2]

spitfire4v8 said:

Sounds very much to me like youve put the pressure feed from the pump to the regulator, and the return line to the other connection on the fuel rail. IE you have your feed and return lines on the wrong way around.

Thanks but that was one of the first things I checked. Luckily I have another
Chimaera close by that I could also check with.
I've also nabbed his fuel regulator and pump which I'm going to swop out in turn
tonight and see one or other or both cure the problem.

[mach2]

Thanks for all the help guys, now diagnosed as a failing pump. New one on order.