Elimination of the sump tank 1988

I am removing the sump tank from my fuel system due to crud build up and rust. I am trying to locate a plug for the return hose to the main tank. Anyone know of a source for a plug for this fitting?

I put a short hose on the tank and put a brass plug in the end of it and clamped it…where the sump tank was I got a fuel filter and put it in there thus filtering fuel before and with the regular filter after the pump.
WIX filter number 33299 with 1/2" spigots for hose…confirm if you like in the “book”…the plug can be made from a brass bolt or for that matter any bolt the right diameter…you could hack saw of the threaded portion and if the bolt has a plain shank under the head just insert it and clamp it…II prefer brass because it cannot spark in an accident or rubbing on something.

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Y’know, you could replace that sump tank with pretty much any metal container with three hose fittings on it. I’ve often wondered if a fuel filter could be found that’d do the job.

I have had good luck with my setup. …just curious. …is there a need to use that extra hose after converting to a filter in place of sump…would that be to insure against air bubbles ?

I went ahead and replaced the sump with a in line steel filter. Much cleaner setup but I want to get rid of the return hose and plug the tank fitting with something that does not look out of place

I see no need for the return line because I now just have a single outlet line that runs directly to the pump with an in-line filter in it

Yes that is like mine. …as I said I made my plug on a lathe then plugged hose…it is under the other stuff and out of sight

I think the whole idea is a bubble separator, so you’d need a way for bubbles to rise out of the top and either head back to the main tank or go directly to the vent system, while fuel is flowing in from the tank and being sucked out by the fuel pump. So, ideally three connections.

OTOH, perhaps you could get by by simply mounting the filter pointing downwards so bubbles can rise back through that 1/2" inlet hose. Or, perhaps a tee in the line right before the filter to connect both the feed hose from the main tank and the vent back to the top of the tank to the same inlet barb.

I’m not entirely sure how big a deal bubbles would be. If they get sucked into the fuel pump they’d presumably get blown around the fuel circuit. They probably wouldn’t enter an injector because that would be downward. They might form a blockage akin to a vapor lock, occupying a high spot in a fuel line and refusing to move. Or they might cause some temporary aberrations in fuel flow, confusing FPR’s and the like. Still, Jaguar went to considerable trouble to make sure they didn’t get into the fuel system, so presumably they’re of some importance.

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YUP dont want ANY bubbles in the fuel supply system, like going around a roundabout an car jerkin and engine stuttering!
when fuel level is low, and gulp of air gets into system!

what thread is the breather pipe tank end , its not metric on my car (pre 88)
bsp or unf or what? when I do this mod does it really need the original filter behind the spare wheel,
ps what happens to the air when a new filter is fitted on an un molested fuel setup?

Every time I got involved with those things, I figured out how to reuse the threaded B nut while replacing the tube and compression seal.

You need a filter after the pump, in case some junk comes out of the pump.

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What happens to the air when a new filter is fitted in an unmolested fuel system?
I am currently seeking a manufacturer for a alloy drifter/surge tank to fit in the trunk, but not where it is now, and a supply filter, regular filter and pump can be positioned under the battery.

Wouldn’t air bubbles pass thru the recirculating fuel and end up in tank .

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scrimbo , you could also get many air bubbles in the INJECTORS , and those cylinders could skip firing!
called shake rattle and roll! course with 12 cylinders some may never notice, altho that type people dont need or appreciate a 12 cylinder car, a nice 4 cylinder for them!

Would it eventually clear up. He is asking about when putting on a filter…surely some air must get in while doing that wouldn’t it ?


let me say it another way!
what if some air displaced some fuel in the injector, then it would run lean AFR, and possibly burn a piston or blow a head gasket!
the situation may happen when low on fuel tank level and sloshing around!
and then again may never happen, its your car and do as you please!

Under pump pressure on a depressurised system it would be blasid round the system and back to the tank.

You hope! ???///

I have changed fuel filters on injected cars since they stopped carbs, there is no issue with air

yes but to ask, why would Jaguar put those swirl units on some cars, and all the work of an air return line from sump tank, so as to eliminate possible air bubbles!

just imagine, if you were running low on fuel , and were driving making turns tight road, back and forth , slosh would have to get into fuel line along with air!

but when you change a filter,then start you may never notice any air and it would /
.should return to tank
be hell on a race track making quick lefts and rights?