3.5 with su hif44

unstable load · Post by **unstable load** » Tue Feb 10, 2015 7:15 am

It won't necessarily be the pump being hoyt that causes vaporization. It could be the under bonnet temperature in general, or the fuel line running too close to the exhaust.
I have heard of guys fitting a slightly overspec pump with a calibrated return line to keep the fuel circulating as a fix.

twin40dave · Post by **twin40dave** » Tue Feb 10, 2015 8:36 am

Hi john
I haven't got any lines close to my exhaust but I haven't a fuel return I gone for the pressure pump
Regards dave

v8250 · Post by **v8250** » Tue Feb 10, 2015 9:05 am

Dave, just another note to help you along. Years ago I had a mechanical breakdown on the inaugural Rally of The Tests driving an MOD V8250. Now, I quietly pride myself in keeping all my cars in mechanically tip-top condition and never have breakdowns that can't be quickly fixed. So, what happens? Middle of the Yorkshire Moors, heavy fog all around, the car stops. It was the fuel pump where some crap in the fuel tank had got through the in-built filter and messed things up. How I got the car going again is a long story best saved for a long beer.

The note is that since then I always install a large fuel filter between the fuel tank and the pump, sometimes with twin pumps in parallel, then a trusty glass bowled Filter King with flow regulator within the engine bay. The reason is that this set up is 100% robust and if a fault appears can be traced in seconds i.e. check flow rate at output of Filter King; job done.

This doesn't solve your current problem but is good food for thought we back up and running.

PS what fuel pump are you using? If an SU pump the points have a habit of failing under load giving the same symptoms as fuel starvation. If so, try a constant 12v pump e.g. a Facet Red Top

twin40dave · Post by **twin40dave** » Tue Feb 10, 2015 11:32 am

Hi thanks for that I'm going to wrap my bowl and pump and get a new coil on Saturday and I will let you all know. The pump is a new hardi and seems to work well but perhaps I should have put it closer to my tank and not in the bay
Ok I will let you know how I get on
Regards dave

v8250 · Post by **v8250** » Tue Feb 10, 2015 11:42 am

twin40dave wrote:Hi thanks for that I'm going to wrap my bowl and pump and get a new coil on Saturday and I will let you all know. The pump is a new hardi and seems to work well but perhaps I should have put it closer to my tank and not in the bay Ok I will let you know how I get on
Regards dave

Hardi pumps are good quality units. Relocating the pump near the tank is best, though do check what Hardi state for their install line/height to fuel tank and if it's best to install vertically, horizontally, or either. Also worth checking the pump's peak constant flow rate.

DaveEFI · Post by **DaveEFI** » Tue Feb 10, 2015 11:55 am

twin40dave wrote:Hi thanks for that I'm going to wrap my bowl and pump and get a new coil on Saturday and I will let you all know. The pump is a new hardi and seems to work well but perhaps I should have put it closer to my tank and not in the bay
Ok I will let you know how I get on
Regards dave

Generally, it's easier to push than suck.

twin40dave · Post by **twin40dave** » Sat Feb 14, 2015 3:30 pm

Hi guys
So been a busy day made a shroud to keep the heat from my bowl and pump and got a new coil all seemed well went for a great run for about 30 mins and then for no reason it started again only 30% power but when I got home and felt my pump and bowl they was cold so now I think I will look for different carbs and relocate my fuel pump nearer to the tank I'm totally baffled now ... I've put it on YouTube under v8 humber it's sounds great ... shame about power mystery
cheers dave

ChrisJC · Post by **ChrisJC** » Sat Feb 14, 2015 9:32 pm

Getting another set of carbs (known good ones) would be a good way forward. I doubt if it's heat in the fuel.

Chris.

twin40dave · Post by **twin40dave** » Sat Feb 14, 2015 10:13 pm

Hi Chris
Yeah I think I'll have to do that and then it's one to cross off the long list but I'm still can't understand what's going on with it