Hi I have a 78 Daimler that has been in storage for 10 years. One of the first things i noticed when i started work on it, is the RH fuel tank was not pumping. The left was fine, i have had it on the road for the last month just using the LH tank. The car was running perfectly last time i had it out. Now it wont start! i have noticed i can not hear the fuel pump when i turn the ignition on, and it is not pumping gas to the carbies.

I have got it down to lack of fuel supply, had it on the road for a month now and everything has been fine, until this morning when it would not start.

The RH fuel tank has not been working since it has been in storage, so i have been running fulltime LH fuel, i suspect i have the same problem on the left as i had on the right before. It seems strange the every thing was fine last week and now i have nothing. Is this a wiring problem or have both my fuel pumps given up?

Could this be a wiring problem or has the fuel pump given up, seems strange as it was working fine on the last outing.

Thanks

Nic

 

Welcome to the forum Nic.

Afraid I can't help you with this problem, but hopefully someone experienced with the older XJ's will be along shortly.

In the meantime why not introduce yourself in our New Member Area - Intro a MUST - Jaguar Forums - Jaguar Enthusiasts Forum

BTW I deleted your double-post & copied the text into this one.

 

Hi Cambo, any chance you could delete the second thread as they both say basically the same thing?

Thanks

Nic

 

Done.

I have no clue about the old XJ's, they have electric fuel pumps? Is it maybe a fuse or bad wiring? (insert Lucas wiring joke here)

But at 35 years of age, it could be that the pumps are just stuffed...

Good luck with it mate, have you got a service manual for this model?

 

haha ! yes i do i have a haynes manual which is really good but it does not have alot of info on this topic except removal of the pumps etc. I will jack it up tomorrow and check for voltage at the pumps, if the voltage is all good i guess the pumps are dead. Just seems odd the left one was fine when i parked it up. . ahhh the joys of classic cars!

 

Nic,

Welcome to our world also.

So a '78 6 cylinder S2 Daimler, NICE.

That would have "in tank" fuel pumps, accessable from a panel just aft of the rear wheels, in the wheel arch panel.

They would have sucked up some serious gunk from the bottom of the tank by now, and the RH one is just weaker and let go before the other one.

Removing the fuel line in the engine bay (obvious precautions) and turning on the ignition should confirm/deny fuel supply.

Some of these had an oil switch just rear of the oil filter that was a "reverse pole" switch, and controlled the earth for the fuel pump relay. So NO oil pressure = NO fuel pump, and the engine fires up on what is left in the carby bowls, and once oil pressure arrives the switch earths the relay, and the pumps pump, and it keeps going. THATS THE LUCAS PART AT PLAY. These switches are notoriously unreliable, sooooo, most cars now have that switch wire permanently earthed, so the pumps work whenever the ign is ON. The inertia switch still takes care of the crash incident/s, so maybe check that it has not tripped, as it will cut the fuel pump circuit dead.

Any which way, those tanks need the plug removing and the gunk flushed out.

A new fuel filter will do no harm either.

 

Thanks Grant, i have taken the fuel line off and it is not pumping, has been wired to pump as soon as the ignition is turned on. I replaced the fuel filter and flushed the LH tank when it came out of storage. I will check the inertia switch though, where is it located?

 

Open the LHF door, it is right there under a black plastic pull off cover, on the "A" pillar, just below the lower edge of the dash timber crash pad.

That's where all my S2 were located.

One of mine really give me the ....., so I simply joined the 2 wires, thus by-passing the switch. Not the safest, but it stopped the cutting out constantly for no apparent reason.

 

Cheers Grant, thats exactly what the problem was, a flick of the switch and shes away! Im in the process of putting a new pump in the RH tank now.