fuel pump

Post by **Jay-Minor** » Sat Sep 08, 2007 8:46 am

my fuel pump is constantly clicking (sounds like it's trying to fill up) and never stops, however there is no fuel going to the carb.
i assume that means it's had it?

Post by **ndevans** » Sat Sep 08, 2007 9:03 am

Have you checked the filter? Also is fuel getting along the pipe from the tank?
Might seem obvious, but is there fuel in the tank? If not the pump will just tick away. You wouldn't be the first to be fooled by a faulty gauge

Post by **Jay-Minor** » Sat Sep 08, 2007 9:49 am

ndevans wrote:Have you checked the filter? Also is fuel getting along the pipe from the tank?
Might seem obvious, but is there fuel in the tank? If not the pump will just tick away. You wouldn't be the first to be fooled by a faulty gauge

yes there's plenty of fuel in the tank (i put £10 in yesterday)

Post by **Orkney** » Sat Sep 08, 2007 9:54 am

Diaphragm maybe if the pump point arent shot which shouldnt be if they are ticking a lot ?

Post by **RogerRust** » Sat Sep 08, 2007 9:59 am

They are very easy to overhual - Just follow the instructions in Haynes.

There is a filter in the pump that might need cleaning and you can clean and reset the points at the same time.

My suggestion is to take the pump off drain the petrol out then strip it down on Newspaper in the kitchen. This is because there are several plastic spacers that fall out and are easy to loose. Don't worry it is an easy rebuild.

I cleaned and reset mine and it went from

Clic, clic,

To Clic, 2, 3 , 4, 5, 6, Clic. If you see what I mean

The diaphrms and etc are available from the suppliers and much cheaper than a new pump.

Roger

Post by **RogerRust** » Sat Sep 08, 2007 10:26 am

Oh by the way here's a tip.

Hold the metal fuel pipe union gently with a mole wrench when you undo the union nut. Sometimes they stick and the pipe twists when you try to undo it. Its not the end of the world but looks untidy for ever more!

Post by **rayofleamington** » Sat Sep 08, 2007 11:02 am

Another comon cause for this is an air leak into the fuel pipe.
Often this can be at the connector between the fuel pipe and the pump, but it could be anywhere in the fuel pipe (most likely you would have noticed if there was a fuel leak though so less likely to be on the section under the car!)

A very uncommon cause is the petrol tank itself. If the fuel can't get out of the tank, the pump just runs on air/fumes. I''ve only heard of this 2 times in 20 years and both times were after a car had sat for ~20 years off road - therefore very unlikely.

If it is the pump itself then it's worth rebuilding. The old pumps seem to have a longer life than new ones, despite being 30+ years old to start with!

Post by **Jay-Minor** » Sat Sep 08, 2007 11:27 am

i removed the filter and it was ok, put it all back together and now it's all working okay (maybe it was an air lock)?

Post by **RogerRust** » Sat Sep 08, 2007 12:19 pm

There is a non return valve in the pump which, if I remember correctly, is just a brass disc that seals against the backpressure from the carb as the fuel is used up the pressure drops and the pump cycles, but it relies on gravity and the back pressure to seal the valve (there is no spring ) even the tiniest bit of dirt lets the fuel drain back towards the tank. The valve is flushed as the pump operate so is self cleaning. However it is this tiny component that regulates the pump or lets it cycle continuously .
I think that is a fair discription of where the problem lies OR is that how the heart works if you need a new valve?

Post by **alex_holden** » Sat Sep 08, 2007 12:33 pm

RogerRust wrote:There is a non return valve in the pump which, if I remember correctly, is just a brass disc that seals against the backpressure from the carb as the fuel is used up the pressure drops and the pump cycles, but it relies on gravity and the back pressure to seal the valve (there is no spring ) even the tiniest bit of dirt lets the fuel drain back towards the tank.

There's actually two check valves. One opens to allow fuel to be sucked into the diaphragm chamber via the filter and the other opens to allow fuel to be pushed out to the carb. They're both accessed by unscrewing the outlet fitting if you want to check their condition.

Post by **overider** » Sat Sep 08, 2007 6:54 pm

I changed a fuel pump earlier this week and had the same problem pump was constantly pumping but nothing was getting to the filter.
I opened the out let pipe and let a bit of fuel pump into a tin then put the pipe back onto the filter and all was well must have been a air lock

Post by **Jay-Minor** » Mon Sep 10, 2007 12:52 pm

all sorted now, went for a 220 mile drive sunday without a hitch

Post by **scotb** » Mon Sep 10, 2007 8:46 pm

wot about electronic pump? ebay number 190151197914?

Post by **bmcecosse** » Mon Sep 10, 2007 8:49 pm

Use it at your peril! Standard pumps give years and years of excellent service - and then only ask for their points to be cleaned. It's a no-brainer.

Post by **overider** » Wed Sep 12, 2007 8:28 pm

I have an electronic pump had it on for a couple of year now I did the John O Groats to Lands end in 2006 with on problems if anything it's slightly noisier than the old ones:

Post by **bmcecosse** » Wed Sep 12, 2007 9:01 pm

I think genuine Burlen ones are ok - but there are chinese copies out there too!

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