Okay, so I’ve replaced the relay, have a new upper fuel pump on the way, and left the battery connected and it was down to ZERO, so I’ve got an electrical gremlin which is not the big concern right now…installing battery shut-off switch for that. The upper fuel pump comes on, the car runs for about 10 minutes, and then dies. Replacing upper fuel pump is easy, it’s the whole sump thing in the lower tank that has me confused. Is there a replacement pump for the lower tank that I can buy? I got the upper pump from Parts Geek. I’ve combed through Kirby’s book and every online forum but I can’t seem to find what I’m looking for here or anywhere else.
…and I don’t want to talk about the spoked wheels or whitewalls anymore, they came with the car.
I’m not sure what you mean by upper and lower pump. To my knowledge your car would, like mine, have just one high pressure fuel pump (there are a few options. Bosch, Walbro, etc). The main gas tank gravity feed down into the sump tank and then that connects to the pump. The pump then pumps fuel through the fuel filter and then up to the engine.
As for the 10 minutes, does the pump die after 10 minutes (followed by the car) or does the car just up and die after ~10 minutes? If it’s the car, your screen in your sump tank may be clogged up. Fuel is sucked from the sump to the pump and pulls rust and particulate against the screen until eventually the flow is obstructed. When the car dies and the pump is off the rust and particulate settles back down. Some people (myself included) have eliminated that pickup screen altogether. You might choose to put an inline filter before the pump if you eliminate the screen.
He’s got an H&E. They have two tanks, and there’s a submersible pump in the lower tank to push fuel back up into the upper one. The upper one is really the lower half of the OEM XJ-S tank, and from there the feed to the surge tank and main fuel pump is the system we’re all familiar with.
I fiddled with the fuel system on an H&E for a few hours once, I couldn’t figure out how to get the fuel pump out. Perhaps it’s a lift out from above sorta thing. We really need to hear from someone better versed in H&E’s on this.
I haven’t personally verified, but the “lift pump” appears to be this:
I’m verifying on a similar post on jaguarforums.com
Good to know! No plans to acquire and H & E myself but now if I did I know at least one thing about them! Kirby with the wealth of info as always! Thanks for explaining to me!
Hi Douglas, replaced the fuel pump and put an inline filter in to replace the lower sump filter. Replaced relay, and the new battery itself was the problem, no electrical gremlin draining it afterall…looked inside the tanks with a lighted camera, and they were remarkably debris-free. Had to drain all the fuel to perform this work, then put in six gallons and the car turns over great (new starter and alternator last year), but it just will not turn over and GO. Do I need to add more fuel? What is the problem? The old fuel pump came on and sounded fine, but I replaced it with a new Bosch. Not sure where to go from here. Any ideas, anyone?
Should I start a new thread on this issue? Thanks!
I’m not terribly clear on the operation of the immersible pump in the lower tank. As I understand it, it’s supposed to run continuously, moving fuel from the lower tank to the upper tank where it can drain to the surge tank and main fuel pump. Why it doesn’t just immediately drain back to the lower tank, I dunno. Presumably there’s a baffle or something. I know that some H&E owners have modified the scheme by putting a small output hose on that immersible pump and feeding it directly into the drain port in the upper tank leading to the surge tank.
Even if adding more gas resulted in it running, it still clearly needs correction. You don’t want to carry around six gallons of gas that you can’t use.
Make doubly sure that both fuel pumps have correct polarity. They don’t work well when connected backwards, and there have been reports that some pumps have a different arrangement of large and small spade terminals than others. Make sure to look for the + and - indications and wire accordingly.
I think your lower pump is bad, and 6 gallons isn’t enough to get any gas into the upper tank. If you put in another 10 gallons and the car starts you know your lower pump is bad
Thanks, Kirbert, I’ll check it out. I think it’s all done right…but not so much if it won’t start and run.
Thanks John6, I’ll put in more fuel and go from there. I’m thinking that’s the problem, but husband disagrees, and I will have him stand corrected. He just doesn’t want to have to drain it again. But if it doesn’t start after more gas, the mechanic said he’d come pick it up and fix it. My guy is really good with cars, but this has been an all-day event more than once now.
If you do need a lower pump, my understanding is they used this Ford bronco pump:
I have yet to independently verify this on my HessJS
Ya just know it was something off-the-shelf. Could just take the old one into an AutoZone and ask for whatever looks similar. Probably not even worth worrying about flow rates; whatever it puts out will be enough to get the contents of that lower tank into the upper tank faster than you’ll use it up.