Leyland P76 Owners 2005

Technical Information

Fuel pump for Six and V8


Wed, 19 Jan 2005
I have been rudely introduced to the fuel pump on my new six P76, in
that it ceased to function. I have pulled it to pieces and and
replaced it with another that I had acquired.
Not really knowing much about these pumps I believe the problem with
mine is that the mechanical lever and spring are not functioning
correctly. The diaphragm was not moving enough.
So my question are,
1/ are the fuel pumps on the six and V8 the same?
2/ where can I get the new diaphragms and valves from? (Goss type
3/ Can anybody disribe the correct functioning of these pumps?
4/ Has anyone fitted an electric pump , what type and were was it
placed in the car? Have you any particular model that you found
5/ If you do fit and electric pump how does the return fuel pipe
6/ What cause fuel vapour lock and if you run a electric pump will
this stop this from happening?
I hope you can help


Date: Thu, 20 Jan 2005
Hello again
There is a spring in the 6cyl pump that occasionally breaks and jamms up the works. (Hyl 1381)
The little lever that goes onto the pushrod is also prone to wear and this can cause the pump to be
noisy and can cause the diaphram to move up and down less than it should.
Some weld on here will also fix this up.
I fitted a "FACET" elec pump on my 6.
It delivers about 3 or 4 psi.
You should mount it at the back, but i did it quick and put it up the front on the Left
subframe rail.
Use a V8 fuel line and bend the return line so it goes the same way as the main line to the left side of the chassis rail.
Its a good idea to blow back through the fuel line with a compressor to stop is syphoning out.
When ever possible ditch the line that goes over the rocker cover, as this is very prone to vapour lock.
I'll send some photos, its all a bit complicated to explain, but the results have been exelent!!

Click on diagram for enlargement

Date: Thu, 20 Jan 2005
The push rod AYH911 should be 38.3 - 38.6 long or even a tad longer to obtain enough diaphragm movement, a dob of weld on the end can fix this.
There may be nothing wrong with the pump at all.
To answer you other question re fuel pumps is that the v8 and 6 are definitely not interchangeable. The fitment of an electric pump (best under the car at the lowest point to help gravity flow) near the back seat floor pan (on the opposite side to the exhaust) will stop fuel starvation.
Also to stop oil leaks the manual pump tends to vibrate and cause the gasket to leak oil.
Cheers Nick.
Date: Fri, 21 Jan 2005
Hello all.
General rule of electric pump is that they are low pressure high volume.
Most setups need a high return flow to tank.
A common pressure is 2 lb but at 120 liters per hour. The bluebird flows this amount of fuel all the way past the needle and seat.
Personal experience with the 6 cyl is to use an electric fuel pump due to starvation and vapour locks.
Hot restarts .
The fuel boils in the lines under the car then to finish the job it travels around the hot engine.
The 6 cyl needs electric fans as it heats up under bonnet area idling and slow traffic.
Wraping of the pipes and added heat sheilding is normal.
The FACET type "rattler" pump is a good choice, you can hear it running.
It is by far the agricultural type of bolt anyplace and it works unit.
I peronally avoid the type with extra non-return valve screwed on to the suction end, as this is often blocked by the smallest objects.
You need to use a vapour return on a 6 cyl with a good fuel flow.
Not as big of a deal on a V8 these normally starve for fuel when high demand is needed due to small pipes and the length of the pick up.
The pump needs to be at te fuel supply.
Rotary vane pumps are much more quiet, but it is important that these
not runout of fuel and have very little resistance to drawing fuel.
They have a better/smoother supply volume as a rule so I would recomend these for V8 owners.
V8 conversion is easy.
Throw away pump.
Fit a plate to the opening.
Use a auto trans cooler pipe bent and cut to reach the original hose.
Fit pump or a surge tank in the rear of the car.
Under the seat is ok as the diff area can get hot.
You need a pump control circiut.
The pump should be wired so that it stops when the engine is stalled.
Tacho/time contol switch-alt operated switch-oil pressure switch.
3 options
1/ remove pump and fit a plate/tasman rocker cover.
Use a fuel filter to join the pipes.
Some cars use filters with theaded fitings so that it can be joined to the original pipes.
Use a clamp to the pump bols.
Put the pump under car.
2/ mount the pump to the rocker cover.
A facet pump will work no worries here.
3/ raid a japanese car "magna" intank pump with a high volume vapour seporator.
Also cars like 200B/Bluebird, Sigma and Starfire Corona.
"david waters"

Last updated
Feb, 2006
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