The Saga Continues!

[V8 Vum]

Those who have been watching my issues unfold are due for an update!

The starting failure has been tracked down to a problem with fuel.

My system has a factory valve coupled to a LP pump, then to swirlpot then to filter, HP Pump, filter, Reg (now showing lower than normal pressure), and rail.

Next job was to find out why the LP pump had stopped making the right noises, and today I found that one of the two pin connector pins had worked its way back into the moulding and was not projecting enough to make good contact. This now corrected (with a hell of a squeeze between engine and bulkhead) and the pump was again making noises....

Ign on and the LP pump sang away with the HP pump momentarily joining with the chorus...even left the LP pump pumping for a good 30 secs or more before energising the hp pump again.....but still low pressure...Dayam!

Next was to uncouple one of the Swirl-pot fuel-feeds and see what was unside...NOTHING! Dry as a witches....!

So...both pumps making noises...fuel in tanks...but nowt in the SwirlPot - so this is why no pressure then!

Dive underneath the car again and uncouple the link feed from the factory valve and the 'IN' on the LP pump, expecting to get drenched in fuel!.....just the slightest hint of wetness dribbing ...but where's the fuel?

Oh .b0llxxxxx!

Do these factory valves ever go wrong?

The valve makes a 'Clunk' sound when energised..but I have no idea if it is working....both tanks have at least a gallon of fuel in each... and before all the running probs started there was even less fuel in the tanks then, but all ran fine, so can't believe it needs more fuel???!

Now I am scratching my head...and not relishing the proposition of having to take the whole darn engine out to get at the plumbing proper!.

Ideas? ...or mabe engine-out is the ONLY option.

...Think I need a break! ....Pizza-time and a Pint! - Give up? Me? Err,,well...maybe!


Keith...feeling very old indeed!

[Storer]

Check the voltage at the valve. It may only be bouncing rather than opening.

Can you easily get one of the valves off one of the tanks.
Check the valve is opening fully.

It is unlikely that both tanks have an obstruction but you could check that too.

Good luck.

Paul

[pilbeam_mp62]

V8 Vum said:

....both tanks have at least a gallon of fuel in each... and before all the running probs started there was even less fuel in the tanks then, but all ran fine, so can't believe it needs more fuel???!

A gallon of fuel is hardly enough to even make the foam inside the tanks damp !! I would not be making any assumptions like "there was even less fuel in the tanks before..."

Get at least another 10 - 15 litres in each tank before you go any further. That's the only way you can say the fuel level is not an issue.

Regards

[Mr Pid]

Would really check fuel level...when I first rebuilt my GTR I (carefully)let 1 tank run dry so I could calibrate the stack dash...found from running dry to full was only 32 or 33 litres. On the basis that the tanks are spec'd at around 40 litres I could well believe that there is at least 5 litres left below the pick up. It would be worth a try to bung a couple more gallons in each !

Stu

[dal2litrefrogeye]

Hi ,also (not trying to tell you how to suck eggs) , but may be worth checking for fuel in tanks with a mecanical devise i.e. a length of mig welding wire down top of tank, just in case between the sender and the gauge, they are telling porkies to how much fuel is in the tank ??? just a thought

[Steve_D]

Do you have non return valves in your LP pipes? Are they the right way round?

Do you have your fuel lines from the tank to LP pumps on the correct tank fittings? They should be on the rearmost of the two lower fittings.

Also agree you need to throw much more fuel in to eliminate that as the problem.

Steve

ETA When you come to calibrate you fuel gauge you should put in a load of fuel then empty the tank using the LP pump. This will establish the effective empty point even if there is still fuel in there.

Edited by Steve_D on Sunday 16th January 22:48

[spatz]

I can agree that if my pumps are starting sucking air it is 32 liters that I can put in there.
So if the tanks are really 40 liters, 32 is what you can use effectiveley.

[V8 Vum]

So trhe concensus is:

1. At least a couple more gallons in each tank
2. Yes I did have a one-way-valve, however I did check when I put it in originally, but to be sure I will check again if I can get the mirror angled right.

I weelly, weelly hope it is going to be that simple!

Thanks to all...

...more to come...

cheers

Keith

Edited by V8 Vum on Monday 17th January 08:20

[pilbeam_mp62]

Any news , Keith ?

Regards

[V8 Vum]

It is, erm, timely, your nudge Kelvin!

I emerged out of my self-imposed depression. what wiv the issues I had, the obvious delight the missus was displaying since the progress had stalled, and the frikkin cold wather...to start getting done-and-dirty with the fule problem...and so I:

Modded the LP pump position,so it is much easier to access without cutting my hands to shreds between the engine and bulkhead.
Rerouted and extended the piping to suit and added a new Speedflow filter + a cut-off valve just before the LP pump, so I could stop the flow if things got out-of-hand.

I will replace the LP pump with another as I suspect (as it is noisy) that it ran dry for too long when the original engine-dying took place....and then filled the RH tank with about 5 gallons for good measure. With all the comments, I was begining to suspect that this pump needs priming before it can 'suck', so with a pretty full RH tank, I juggled the cut-off valve with cracking the joints in turn un til I was confident the pump was flooded.

...and BAM! - the engine burst into life! - went back indoors with a very wide smile on my face...to see the missus looking very peed! She had heard it!

...and so I will replace said pump, and get on with the electric now ! Raaaaayyy!

I am still VERY confused though?
Why with only a gal each side originally, did all behave as expected first start(and ran for 10 mins overall)...but simply would not this time around until I had put a TON of fuel in???? Perhaps I am missing something!

I have learned my lesson...this LP pump appears not able to draw fuel unless properly primed...maybe this is too much to ask considering it has to 'pull' through the factory valve unit in its mounted std position?...so god forbid running out on the road!

Thanks to all for your moral and practical help...sincerely!

...on the the next set of challenges...;)

cheers

Keith

[UltimaCH]

Good to hear that progress has been made, even if it was at the price of a slight depression and the wife being p***ed off. I can't imagine that my build will be easier and considering also that I wouldn't be able to rely on local knowledge, but this forum will certainly be hard pressed with questions...

[pilbeam_mp62]

V8 Vum said:

A fair amount of flannel - but bottom line was the engine wouldn't start because it had run out of petrol !!

Very glad to hear that it was a simple fix.

Good luck with the rest of the build.
Regards

[GTWayne]

Interesting that you should use the word 'Saga' in your thread title Keith but I guess it is a worthwhile organisation to be involved with at your time of life. Keep on truckin' there good buddy

[V8 Vum]

GTWayne said:

Interesting that you should use the word 'Saga' in your thread title Keith but I guess it is a worthwhile organisation to be involved with at your time of life. Keep on truckin' there good buddy

- somewhat of a freudian-slip methinks, Oh DARK and MYSTERIOUS one! When you comin' out to play again? Don't leave it too long, I don't want of have to bringout my shiny new V8 Zimmer and twin-turbo-slippers!



K

[GTWayne]

^^^ Tell you what Keith, I'll show you mine if you'll show me yours
It took 5 years to turn the GTW from concept to reality so hang tight old friend, you are in good company.