Fuel Tank Thread

[AndyH]

Hi,

Just starting to connect up the fuel system... The fuel tank I have has two outlets at the bottom. Both are threaded.

Not sure what the thread size is.. 1/4" BSP is the closest, but still does not feel right.

From the usual parts catalogues, it looks like it's more likely to be 1/4" NPTF.

Can anyone remember.?

Regards
Andrew

[DavidM]

If they are Hawk recent tanks then they are M14x1.5 at least that is what mine turned out to be. DavidM

[AndyH]

Hi,

My Hawk is about 2 years and 8 months old... Not sure if this counts as recent??

The M14 you quote must be the "fine" thread.. I've tried M14 Coarse and no good.

Regards
Andrew

[DaveAk]

Sorry I can't help with your enquiry Andy, as mine is a much earlier Transformer, but can I hijack you thread to ask about a related matter.

Diameter of lower outlets on older Transformer tanks is about 8 mm, (unthreaded) I have been informed that this is quite narrow for the size of engine and is likely to be causing some fuel starvation problems now I have Alfa V6 fitted, has anyone had this problem? do I need to fit a swirl pot?

I continue to expereince occasional misfire, definately on full power.

Any help appreciated - thanks

Dave

[chris.richard]

Diameter of lower outlets on older Transformer tanks is about 8 mm, (unthreaded) I have been informed that this is quite narrow for the size of engine and is likely to be causing some fuel starvation problems now I have Alfa V6 fitted


Remember you have two of them though ;)
Assuming you feed your pump from both tanks via a T-piece.

[guy mayers]

I had a problem with the tanks with the Volumex installation and a high pressure pump.... The fuel obviously needed a return and the pump was supplied via a T piece. It would draw fuel from both but the return led to an overflow from from the overfilled return tank. Hardly ideal. I don't think the tanks/lines were blocked anywhere, just the diameter of the pipe restricting flow. It happened just once. At the cars' first MOT test. The first mod was to have some larger pipes welded on and I'd recommend that there isn't a T in the balance pipe and that fuel is drawn from a separate union on the same tank to which the return feed goes.
Having used the Alfa 164 pump, buried in the nearside tank, I've never experienced any problems with fuel supply.
Guy

[chris.richard]

I have a large (15 or 18mm?) balance pipe straight between the tanks, as well as the 8mm feeds from both to a t-piece to 10mm pipe to the pump. Vent pipe from nearside tank into offside tank, then rollover-valve protected vent-to-atmosphere from offside tank. Does that make sense?

[roger001]

I had no problems, when using a 12v engine and a single tank even at racing speeds. The only time I had fuel starvation was on an exceptionaly long corner when the tank was low and suffered from fuel surge.

[pimms]

I have a large (15 or 18mm?) balance pipe straight between the tanks, as well as the 8mm feeds from both to a t-piece to 10mm pipe to the pump. Vent pipe from nearside tank into offside tank, then rollover-valve protected vent-to-atmosphere from offside tank. Does that make sense?

Chris,

I was planning the same construction, but do you use filters between tank and pump ( as well as after the pump )? If so what type of filter?

Thanks,

[chris.richard]

2 of these between tank and the t-piece (http://www.demon-tweeks.co.uk/products/ProductDetail.asp?cls=MSPORT&pcode=MOCSLF7-8)

one of these after the pump (http://www.demon-tweeks.co.uk/products/ProductDetail.asp?cls=MSPORT&pcode=FSEIF2208)