Vapour lock

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Mr Don
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Vapour lock

Post by Mr Don »

Our Beryl 1965 1098cc Moggy arrived with a nonstandard fuel pump. About two months ago this pump started to die, the diaphragm appeared rather hard and it was unable to pump when the car was ascending a long hill. As I did not have much money at the time I made the mistake of purchasing a cheap replacement from ebay.. The pump was in fact quiet a good one, called a Facett. It has good feedback on the tinterweb, but it did not work well on the Moggy. I had fitted it in the engine bay near where the standard pump goes. The pump has a metal case, when the engine was hot and the car stationary the pump got hot too. This caused a vapour lock in the pump and fuel pipes :cry: . Letting the car cool for two hours was the only solution. The car started well, went very well but if you stopped in traffic or the petrol station it was stopped for the next two hours. I have now shelled out and purchased a new SU pump and fuel lines from ESM and the problem has been resolved :D .
bmcecosse
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Re: Vapour lock

Post by bmcecosse »

The Facett pump would be fine - if installed as the manufacturer intend - with a flooded suction! Very few pumps can work as the Minor SU pump does - sucking fuel up to a level high above the tank. The Facett pump could either be sited at the back low down next to the tank outlet - or low down on the engine bay tie-plate at the front. It was never designed to 'suck' fuel...... If installed as I suggest - the delivery pressure may well be too high for the SU carb - and a pressure regulator valve may be required.... There will be NO 'fit of the vapours' though - which can still happen with your high mounted SU pump.....
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Longdog
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Re: Vapour lock

Post by Longdog »

Hi I have fitted a Facet pump next to the outlet of the fuel tank and have never had vapourisation problems.They are very reliable, don't have points and are dirt cheap compared to an SU. I did however fit a filterking with mine so that effectively made the first installation about the same price.
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pegasus
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Re: Vapour lock

Post by pegasus »

I used to fit this make of pump to rover p6,s, They are designed to push fuel not suck. As already mentioned they should be fitted close to the tank.

Mark
http://www.mig-welding.co.uk/forum/showthread.php?t=12994[url][/url]
RobThomas
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Re: Vapour lock

Post by RobThomas »

The one you ideally want is P No. 40105. About 2psi output rather than the 4.5 psi or higher versions. Works well enough to be standard fit on Rutan aircraft.
Cardiff, UK
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