Ethanol and Hawk fuel hoses

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peterc
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Ethanol and Hawk fuel hoses

Post by peterc »

I have been having issues with getting sufficient fuel pressure from the Malpassi fuel filter/ regulator. The screw is currently wound so far in there is no thread left for the domed lock nut despite only 4.5 psi.

Brian of BGC Motorsport advises that I first need to check that the pump is well earthed as it should give 6-8 psi.
He has been aware of issues where the pump works but does not perform to full performance due to poor earthing.
The Malpassi has an adjustable range of 1.5- 7psi.

He also advised the following regarding the fuel hoses that he has supplied as part of the Hawk kit.
Quote
Modern Fuel is horrible stuff and attack the hose and can form a gel if inactive for a while, The kits I build now uses a different hose and although the original hose is rates for 10% ethanol, the hose does not last the same as it used to , probably due to other additives that the fuel companies do not disclose.

So you have been warned.
Peter C
cobraboy
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Re: Ethanol and Hawk fuel hoses

Post by cobraboy »

I had an issue with my filter king that you may wish to check out.
I too had screwed the top screw right in to try to get more pressure. It did not seem to make any difference where the screw was to the reading I was getting, so I took the filter bowl off to check the filter and found parts from the adjuster in the bottom of the filter. I found that if the top screw was over tightened slightly it 'jacked' the assembly out of the top lid into the filter.
I had to re assemble and re stake into the lid.
I also found that the spring in the top had a sharp edge on one end, this had dug into the fitting and the spring had been twisted and ruined by the screwing action, I had to replace the spring. There are three types of spring for various pressures.
Here is one, others are on this site. https://www.fuelpumpsonline.co.uk/malpa ... 5286-p.asp
I can only get 4.5 psi from my Facet cube pump that is listed at up to 7 psi, I did a flow test though and the GPH is adequate. The car does not run out of fuel at WOT, so I have let it be.
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peterc
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Re: Ethanol and Hawk fuel hoses

Post by peterc »

Yes, I had my Malpassi fall apart when on my way from Silverstone to the hotel last year. Not a pleasant night being recovered by the AA.
I have re assembled the old unit and re staked the plastic collar which had fallen out of its own accord. I say this as I had never made any adjustment.
I have checked the new unit for the same issue with the collar but not inspected the spring. I didn’t want to dismantle the unit due to infringing any warranty. Thus I will check the voltage at the pump first.
It’s interesting that BCG suggest the creation of a gel in the hose which of course could foul the regulator.
The do gooders who suggested adding ethanol have a lot to answer for. I hope their cars have issues to show them what they have created.
Peter C
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