> ----------
> From: Michael D. Porter[SMTP:mdporter@rt66.com]
> Reply To: Michael D. Porter
> Anthony Gordon wrote:
> >
> > The vapor lock problem seems to be well known. The solution is to do
> one
> > of two things. Buy or construct the cooling loop system that allows the
> > unused fuel returning to the tank to conduct heat away from the Lucas
> > winscreen wiper motor adapted to become a high pressure fuel pump (how
> do
>
<Two other possibilities--the first is relatively cheap--provide a
<priming pump to feed the inlet of the pump. Second, more
<expensive, is
<,to replace the Lucas pump with a Bosch model (quite <common
swap).>
Sure COMMON BUT NOT WITHOUT ITS OWN PROBLEMS. best use the priming
pump, say a low pressure solid state pump.
<I wonder, however, about the cooling coil around the pump. <At
least in
<the case of the Bosch pump, fuel circulates through the <pump and
motor
<internally, so the temperature of the fuel would be raised <passing
<through the pump, anyway.
<It seems far more logical to keep the pump outside the car <where
it's in
<the airstream, and, if need be, provide some sort of heat sink <for
the motor case.
True, but that'll expose it to the elements and you need to make sure, that
its well sealed, otherwise it will only run for about three years and then
the electrics will play up as anyone playing with hot Minis will know.
Nevertheless this is probably the best solution.
> <Further, if it's below the tank just enough, head pressure
<in the tank will help feed the inlet. After all, vapor lock is
<common
<enough in hot climates with carbureted cars--and it almost <always
occurs
<on the inlet side of the pump, causing the pump to starve <and lose
<prime. Same principle should apply with a high-pressure <electric
pump.
Too true, could even save you the priming pump.
<The best cure, to my mind, would be one which insured flow i<nto
the pump
<inlet.
<Beyond that, the fuel calibration is very likely dependent <upon
fuel
<pressure, since it's entirely mechanical, and in such a <system,
rate of
<flow is affected by pressure. I'd have to see the innards of the
<metering unit to be more positive about that, though.
Another comment, I have read prices of reco metering units, which read a bit
too low for my liking, make sure you look at the unleaded section of the
reconditioned units, otherwise the thing just won't run lng enough to
justify its price.
Next comment is that the cr of injection engines is higher than at least the
one of late ec engines. As the petrol tank of the injection model is
different I have thought if there is any need for a revision of the tank.
IMHO its not as long as you have a late model as you could use the ec pipe
stud on the petrol tank for your fuel return.
Any comments?
Cheers, Gernot
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