MK2 Jaguar Fuel Pump

Seeing as this place is a wealth of knowledge, I thought I would ask for some help regarding a MK 2 Jag.

So the history is that this car was working fine, it then sat idle for a short while, and now will not start. On turning the ignition, no fuel pump can be heard.

I have attached a couple of pictures which I hope help. The wiring seems a little odd to me, you have 1 main thick white wire coming in on the right hand side, this then has a connector block, the wires have bullet connections that plug into this. The 1 main wire seperates to 2. Coming out of the connector there is a blue which goes to the top of the fuel pump and a red which attaches to a 'round shiny thing' which has a plate that attaches like a normal earth to the chassis. Any paint has been removed from the chassis where it attaches and I have cleaned all connections up to ensure a good contact. But it does not work. This is how the car was when I started looking at it.

I have tried attaching a 12v supply. the positive supply going to the blue bullet connection. I then unscrewed the 'shiny thing' and attached the negative supply directly to the black earth lead, so eliminating the red wired 'shiny thing'! It sparked and you could hear the pump clicking.

I then tried removing this shiny thing and attaching the earth lead from the pump to the same place on the chassis, and nothing.

I hope I have explain ok Can anyone suggest any ideas please?

Follow that white wire back mate there will be a duff relay there somewhere

The white wire goes behind the wheel arch and I have no idea where it goes from there?

I don't understand how you can have the pump earth and live, connecting to 1 wire?

Early cars were positive earth , the shiny thing is a capacitor as I remember to prevent sparking at the contact points - usually the points need cleaning or are stuck - there is a electronic version without the points in the pump available that prevents the no start issues - not sure of they are also available in pos earth

Thanks Jagman, I have been reading up a bit about the early cars being positive earth. This car has had a huge amount spent on it, everything in the engine bay, underneath and inside looks like new.

Where are the points that may need cleaning? Although surely they must be ok or it wouldn't work with a 12v supply straight to it?

Points are in the top cover , but your pics don't look like a jag pump

Its definitely not a jag one no. I've got 2 other mk2's sitting here which are clearly original. This is certainly an aftermarket setup

Looks like someone's mixed up old and new wiring - the capacitor is connected from supply to earth - so is acting as a "smoother" to remove any ripples in the supply - ( probably unnecessary ) but this has failed and dragging down the supply to earth - that's why when it's disconnected the pump clicks and runs -

Just run the one supply wire ( check it's voltage) and make sure the pump is bolted up to chassis ( earth return)

I'm assuming it's neg earth car - ( check battery connections)

Mk11 jags like a lot of fuel flow or power drops off so a good pump is needed and clean filter , a 3.4/3.8 in good tune should keep up with most modern saloons , I fitted a manual xjs box in mine - loved it !

well ive stripped the pump out the car so I can test it properly on a bench. When I connect a power supply you can hear the pump click once then nothing, disconnect and reconnect and it clicks again. I think there is something wrong with it. I'm going to strip it down, perhaps the points need cleaning up. It seems like something is stuck in it?

The original pumps in the MKII were made by SU and had a black plastic cap over the points, held by a knurled nut and a hex nut that doubled as the negative feed wire terminal. (Cars were positive earth). Some, if converted to an alternator, were also converted to negative earth. That's an aftermarket pump, and it appears it's buggered. Check you are feeding it the correct polarity on the bench, try tapping it hard, and if still no joy get a new one. That awful plastic hose goes rock hard and is a leak-in-waitig, change it for modern lead free fuel compatible black "rubber" hose.