A long slog: RF Fueling Problem

[Chris Wallace]

I purchased my RF GT40 11 months ago. The owner said it was ready to go. Now, 500 hours of hard graft later, it is indeed ready to go. The most difficult problem of the 53 I bothered to record was the overflowing of the fuel tanks when full or nearly full. RF were less than helpful on this serious topic telling me they had changed the set up to include a cross over pipe[ like the originals] to solve the sort of problem I had. After many hours on the hoist ang lots of money later I came to an alarming conclusion. When running on , say, the left tank the right lift pump will transfer incremental amounts of fuel to the system even without being on. The result can be an overflow of the left tank. The reason for this seems to have escaped RF as has a very simple and cheap solution. What is happening is this. The lift pump is rated at 4 to 7 psi and has a check valve built in. BUT it only has a 1 to 2 psi spring loaded ball bearing to give it some back pressure. When switched off, fuel free surfacing in that tank will slosh forward and back overpowering the ball bearing and adding to the returning fuel. The solution is to fit a shut off valve after the lift pump and wired to it. {Both pumps} In my case the SOV screwed straight into the delivery side of the lift pumps and the problem ended. Cost $60 each. I hope this was of some help. Alas, my wife has long since refused to believe the car is safe and has refused to believe me when I say it is now fixed.

 

[Gus Richmond]

Re: A long slog.

Hi Chris, Welcome to gt40's.
Good to hear its sorted and ready to go. Any chance of posting a few photos?
Cheers, Gus.

 

[Cliff Beer]

Re: A long slog.

Chris, congrats on getting the car up and road ready.

I guess compared to a 6,000lb Chevy Suburban with 10 air bags and all kinds of impact protection just about any GT40 isn't safe....but when did that matter all that much? And, only one way to prove to her it's fixed: take her out in it for a high speed run...see if you can hit 140 or so. I don't think she'll be doing much talking and doubting....

 

[Chris Wallace]

Re: A long slog.

Hi Chris, Welcome to gt40's.
Good to hear its sorted and ready to go. Any chance of posting a few photos?
Cheers, Gus.

Hi Gus.I have lots of photos but find this site a bit overpowering. How and where do I make it happen.? Also, where are you ? Right now I am in Tasmania but soon will be returning to NSW> Near Port MacQuarie. Regards Chris

 

[zollis]

Re: A long slog.

Hi Chris,

I am not an IT boffin but I can try to help you uploading pics for this site.

1) Click on the "Go Advance" -- instead of Post Quick Reply

2) Now scroll down to " Additional Options"-- it is the second frame down.

3) Click on " Manage attachments"--- a second screen will open

4) Click on " Browse" -- will open pics in your computer.

I hope it helps.

One thing --- the pic size must not be too big.








Z.C.

 

[Dave]

Re: A long slog.

use a pollak valve to isolate tanks and feed to a swirl pot.....I cant see how this is RF's fault.

 

[Chris Wallace]

Re: A long slog.

use a pollak valve to isolate tanks and feed to a swirl pot.....I cant see how this is RF's fault.

Hi ,Yes, a Pollock valve is an answer but I chose individual valves from a company specialising in gas conversions. Their valves screw straight into the lift pumps. Given that I have been in near daily conversation with RF over the fuel tank emptying over the paintwork from the filler cap... and RF providing the build but no answer other than " We don't have that system anymore and can't help you" I think it is fair comment to say they knew or ought to have known that this problem exists in early cars. Under the right fuel load conditions someone will go up in a sheet of flames. So, yes, it is RF's fault. Safety is everything.

 

[Dave]

Re: A long slog.

Mine doesnt do that .......maybe your workmanship is a consideration?

So let me get this straight in my head

1 - You are blaming the new RF for a design fault of the old RF that the new RF have rectified for the new cars? Why not buy the updated parts?

2- You bought a near finished car from someone and are crying because RF wont help you apart from telling you they have a new system that works but you dont want to buy it?

3- you found 53 problems with the car.........you bought a shitter that's your fault.

 

[Chris Wallace]

Re: A long slog.

Thank you for your reply.I have always found that it is possible to make cheap and unhelpful comments...which is why I don't. My list of concours wins with Jaguars[ XK150s, E Types , SS100 and owning XK8, XJS. Mk2s etc plus Aston Martin DBS /OHMSS ] should qualify me to know the mechanics of what is a fairly straight forward car. The mistakes I found were c/o the previous owner. The fact that you are so hostile is a puzzle. Wasted energy. I do not wish to have the last word so leave it to you. Perhaps my standards are just too high. Who knows. Who cares. Life is too short.

 

[Dave]

Re: A long slog.

I guess my reply comes from the fact that your first post was basically a kick in the guts to the previous owner and to RF for not dancing the tune you wanted.

Sorry Mate Im sure you build a good a car.

 

[John]

Re: A long slog.

I on the other hand can easily see where and why Chris is coming from, people do tell porkies its a fact of life, I at present in my shed have a Locost lotus 7 that was sent to me to finish off, "its about 80% done "says the owner, so I took him at his word, it arrived a fortnite later toward the end of November last year, I have worked an average of 5 hrs a day on it almost everyday since, and I would say its now about 75% finished. and i'm not building it to concours level either.
as for the fuel system all the factory had to say was yes there was a problem, and this is how we rectified it, dosnt take much to be helpful.

cheers John

 

[Gus Richmond]

Re: A long slog.

Hi Chris, I in Mandurah WA. It does supprise me Paul has not had a solution at hand for you. My car has an older spec tank set up. Paul had no dramas with supplying the bits to make sure there was no problems with it. It should be good to go for me, that included up rated filler necks and breather tube as well.
Cheers, Gus.

 

[Dave]

Re: A long slog.

John the difference with your car is Ibrahim is paying you to finish his Locost. Also the factory (RF) did offer a solution but that was not what old mate wanted.

 

[Ron Earp]

Re: A long slog.

How about we move this to the fuel technical area? The Introduction forum isn't a sounding board.

 

[Robert May Eng.]

I purchased my RF GT40 11 months ago. The owner said it was ready to go. Now, 500 hours of hard graft later, it is indeed ready to go. The most difficult problem of the 53 I bothered to record was the overflowing of the fuel tanks when full or nearly full. RF were less than helpful on this serious topic telling me they had changed the set up to include a cross over pipe[ like the originals] to solve the sort of problem I had. After many hours on the hoist ang lots of money later I came to an alarming conclusion. When running on , say, the left tank the right lift pump will transfer incremental amounts of fuel to the system even without being on. The result can be an overflow of the left tank. The reason for this seems to have escaped RF as has a very simple and cheap solution. What is happening is this. The lift pump is rated at 4 to 7 psi and has a check valve built in. BUT it only has a 1 to 2 psi spring loaded ball bearing to give it some back pressure. When switched off, fuel free surfacing in that tank will slosh forward and back overpowering the ball bearing and adding to the returning fuel. The solution is to fit a shut off valve after the lift pump and wired to it. {Both pumps} In my case the SOV screwed straight into the delivery side of the lift pumps and the problem ended. Cost $60 each. I hope this was of some help. Alas, my wife has long since refused to believe the car is safe and has refused to believe me when I say it is now fixed.

Chris well done for wading through the shake down problems. Many would have done the bare minimum, got it running and just used the car . At least you have been thorough and know the car is safe for purpose.

Bob