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#Post#: 58453--------------------------------------------------
Fuel pressure aka Vapor lock.
DIR By: MANILA THRILLA
Date: April 24, 2013, 6:43 am
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Hi all,
What is the correct fuel pressure (Petrol) with the standard
fuel pump ? ( the one with the glass bowl )
Would it be advisable to use the diesel engine fuel pump.? Fuel
pressure is higher right ?
How about using a electric fuel pump ?
Having problems with vapor lock I think. Series starts in the
morning, runs well. When shutting down and starting right after
no problem. After more than 30 minutes shut down it starts, runs
for a minute and stops. No chance to restart, after engine has
cooled down no problem. Carburetor is a Weber. Rotten hot here
in the Philippines .
Thanks.
Helmuth
Series III-88 SW petrol
#Post#: 58569--------------------------------------------------
Re: Fuel pressure aka Vapor lock.
DIR By: MANILA THRILLA
Date: April 25, 2013, 2:15 am
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Would anybody care to comment ??
#Post#: 58578--------------------------------------------------
Re: Fuel pressure aka Vapor lock.
DIR By: gilbo
Date: April 25, 2013, 3:07 am
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Oh go on then :smile1
I suffered vapourlock no matter what carb I had/have fitted. I
have had the Zenith, single choke Weber and now run a twin choke
(and manifolds from a 89+1).
I think part of the problem is that I do not run the mechanical
fan (I have an electric one which hardly ever needs using over
here!). The heat from the exhaust manifold comes straight up
under the carb when the engine is stopped and the boiling point
of petrol is pretty low (I think?) so the fuel in the float
tends to evapourate.
So - what did I do - well in the end I have fitted an electric
pump (Facet) in line with the existing mech pump so I can press
a button to energise the pump and re-prime the system before I
try to fire up. Works for me!
By the way when you get this problem have you tried manually
priming the pump?
There is a guy in Mexico who used to frequent the Series2 Club
who had similar problems due to the heat - think heis name was
Rainer?
HTH
Dave
#Post#: 58579--------------------------------------------------
Re: Fuel pressure aka Vapor lock.
DIR By: Jagger
Date: April 25, 2013, 3:10 am
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Hi Helmuth.
It sounds very much like mine did when the electric fuel pump
failed so I think you're on the right lines.Worth trying another
fuel pump.
Mine has a V8 conversion with electric pump so I can't comment
on the diesel pump idea.
#Post#: 58604--------------------------------------------------
Re: Fuel pressure aka Vapor lock.
DIR By: Huffo-James
Date: April 25, 2013, 7:07 am
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If the one-way valves in the fuel pump stop working properly,
the engine will run but may stuggle at high revs and/or show
symptoms of vapour lock in hot weather.
Not experienced this myself, but read about it in old copies of
the various Land-Rover magazines.
I think somebody posted some instructions on the old forum for
renewing the one way valves.
Cheers
James
#Post#: 58614--------------------------------------------------
Re: Fuel pressure aka Vapor lock.
DIR By: MANILA THRILLA
Date: April 25, 2013, 10:04 am
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--- Quote from: gilbo link ---
>
> Oh go on then :smile1
> I suffered vapourlock no matter what carb I had/have fitted. I
have had the Zenith, single choke Weber and now run a twin choke
(and manifolds from a 89+1).
> I think part of the problem is that I do not run the
mechanical fan (I have an electric one which hardly ever needs
using over here!). The heat from the exhaust manifold comes
straight up under the carb when the engine is stopped and the
boiling point of petrol is pretty low (I think?) so the fuel in
the float tends to evapourate.
> So - what did I do - well in the end I have fitted an electric
pump (Facet) in line with the existing mech pump so I can press
a button to energise the pump and re-prime the system before I
try to fire up. Works for me!
> By the way when you get this problem have you tried manually
priming the pump?
> There is a guy in Mexico who used to frequent the Series2 Club
who had similar problems due to the heat - think heis name was
Rainer?
> HTH
> Dave
>
--- End Quote ---
Thank you gilbo,
I also had a Zenith before I changed to the Weber. Same Banana
really in terms of Vapor lock. Weber is better in fuel mileage
by far. I do around 250km on a full tank (45L)
Will install a electric facet pump as you suggested.
The heat from the manifold goes straight up to the carburetor, I
measured 85-93 degrees C !! Boiling point of mogas is around
that number....
I tried manually priming the pump, engine starts and runs for
about 3 minutes. Just enough to get out of a parking lot and die
in the middle of a driveway rofl
I do not know Rainer.
Today we had bloody 40 degrees C !!! drink(*&
Thanks again for your very helpful input.
Cheers
Helmuth
#Post#: 58615--------------------------------------------------
Re: Fuel pressure aka Vapor lock.
DIR By: MANILA THRILLA
Date: April 25, 2013, 10:06 am
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Thank you Jagger and James. :)
Cheers
Helmuth
#Post#: 58617--------------------------------------------------
Re: Fuel pressure aka Vapor lock.
DIR By: gilbo
Date: April 25, 2013, 10:38 am
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No problem helmuth.
Just so you know I bought a low pressure Facet (about £30 here
off ebay) and fitted it into the feed from the tank to the
nornaml mech lift pump. I did wonder if it would restrict the
flow but it doesn;t apear to and the lift pump still works
happily too. I also put an inline filter so it goes....Tank,
filter,facet pump, lift pump,carb. I only use the electric pump
to prime the carb - after that I fire up and the lift pump does
the business. Did consider using the electric pump ony but then
thought about 'shock' switches to kill it in the event of a
bump!! ALso the reliability - lift pump simple!!
Anyway ggod luck!
Dave
#Post#: 58703--------------------------------------------------
Re: Fuel pressure aka Vapor lock.
DIR By: MANILA THRILLA
Date: April 25, 2013, 11:10 pm
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Hi Dave,
thanks again. :smilewide:
That is exactly what I will do also.
Cheers
Helmuth
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