FUEL SUPPLY FAILURE

[ROSSYSTEVE]

Hi all , this is my first posting here following on from the article in this months mag about the website.
And by coincidence I have a problem that I could do with some advice on..
On the way back from the Northern show yesterday, I switched tanks from left to right doing about 65 and within a minute the car started to die.
I switched back to the left tank and it immediately picked up. The swap over has been previously fine.
So obvious questions..
pump failure ? ( submerged one )
elec supply ?
Fault finding suggestions.
I have a jaguar issued xj6 Daimler Soverign manual published by British Leyland publication part no E188/3.
But I have not really found it useful for diagnosing the problem.
Any suggestions would be gratefully recieved before I contemplate draining £40 worth of juice and simply swap the pump .
Thanks Steve Ross.

[almcl]

It might help if you said which model and year of car you have. The solution will be radically different for a carburetted engine compared with a fuel injected one, for instance.

[ROSSYSTEVE]

Dhooo ! Its a 1976 daimler coupe twin carb..

Thanks, Steve.

[almcl]

OK, got it. You have the twin submerged fuel pumps?

The pump is accessed via a plastic cover at the back of the rear wheel arch. You should find the fuel pipe (possibly covered in coiled plastic) emerging from the cover. It is held on with 4 self tappers. Getting these off can be interesting, so you may want to listen for the pump running before trying. With the engine off and ignition on you may need to ground the lead to the oil pressure transmitter at the back of the block to get to the pump to run. Not all cars have this and sometimes a previous owner has removed it.

If the pump doesn't appear to be running then it has to be investigated further. Remove the cover and establish that 12 volts is arriving (the fuel changeover switch can fail.) If the pump won't run with 12 volts applied then it has to come out and, probably be replaced. New ones are available from the independents.

If the pump is running but the engine doesn't, post back an we'll go down that route
.

[ROSSYSTEVE]

Al, many thanks for that, I'l let you know how things progress.

Cheers Steve.

[ROSSYSTEVE]

Sorted the problem monday afternoon, got a genuine jag pump from ebay for £35! compared to £70 or £76 from Barrats and Manners.

So it all came apart easily enough and boxed up without too much of a hitch, gasket leaked first time so cleaned up tank side and smeared a bit of copperslip on the face and tapped each ring tab to ensure even and parallel compression.
Topped up the tank and switched to that tank on the dash when running and yes, it carried on running for the rest of the test run ! happy bunny !

til next time, cheers Steve.

[almcl]

Well done and thanks for posting back to let us know!