Thanks, that makes sense. I have a filter in the engine bay and I will leave it there for originality.

 

Quick question:

Is there a fuel drain in the fuel sump tank on PreHE models ?

Haynes describes draining the tank using an extension on the fuel pump feed hose through a drain grommet in the boot floor, and the manual is based on a PreHE XJ-S

Could someone share a picture of the grommet to remove to access the drain to help me determine if it exists on my car ?

 

the easiest way is to slide under the rear of the car and look for a plastic grommet about 1" diameter that is about a foot outside of the trunk floor rubber drain. Your going to be positioned directly under the battery box.

 

Thanks !

Yes, there are a drain plug. It did not align well with the hole in the floor, so I had to remove the bolts holding the sump tank to get it in line
I tried to loosen the plug using a spanner from the boot side, no luck. It did let go when I used a top from below. 11/16 size.
Fuel just started dripping now, there was only 6-7 litres left in the tank. I had been brave when I drove it home with the fuel light on...

 

Since you are that far down this trail you might consider just taking out the sump tank and opening up the access ring retainer to clean the inside of the tank. Did wonders for me. You've done the hard part by draining the tanks and getting the sump tank bolts out.
I went the whole way by cleaning, washing and touch up painting everything around the sump tank and battery tray area. Looks like new now.
REMOVE the battery before you go messing around with open fuel and vapors back there.

 

Battery was removed quite early in the process, no reason to take stupid risks
Sump tank is already on my workbench, and the fuel pickup is removed. Retainer came of easier than expected.
There was a fair amount of grit in there, and the filter surely needs to be exchanged.
The hose clamps on fuel lines were very lightly tigthened. I guess it's due to setting of the rubber material after many years of clamping. I suspect these lines may be original, alternatively from 1989, when the car was refurbished...

There will be pictures when I get to work from my PC. Phones are smart, but I'm not patient enough to use it for advanced forum functions

 

Regarding that rivet... Wouldn't it just be easier to put a small dent in the tank in that area? I mean, that would solve all possible future rubs and those 10 ml of fuel less shouldn't hurt your range

 

I'm for sure pulling the tank just to get to the bottom of things, and you're right Daim: It should be easy to adapt the tank to give room for the rivet.

 

I just did this project about weeks ago. y progress is in a previous thread. I used Muratic acid to clean the inside of the tank. I got it at the Hardware store. Don't leave it in too long but it really cuts the crud and rut build up. The instruction say to mix it 50/50 but I found you probably want to go to a higher concentration, maybe 70/30. Swirl it around, seal up the holes and rotate the tank onto each side and it sit for about 10 minutes. Swirl some more and drain then rinse.

Almost certainly the hoses are all original. Easy to replace. Recommended due to their age.

Getting the main tank out was a challenge. The bottom of the tank had rusted and bonded to the foam padding. My eventual solution was to get some liquid dish washing soap and wooden paint stir sticks. I coated the stir sticks in the soap and worked them under the tank lubricating the surfaces. It took a while but it worked.

Label all the hoses and anything else your take off to help with reassembly.

 

Fuel tank is out, and I'm glad I did it. It has a lot of surface rust at the bottom face and possibly pinholes when I get rust removed. Rust on lower left front edge is a bit darker than the dry rust indicating that this area is not dry...

I used a piece of thin sheet metal 30x45 cm with rounded corners to get the tank bottom seperated from the foam. Sometimes it pays off to never throw anything away, I'm not sure how long time this sheetmetal piece has been lying around not being useful.

I first tried to get right end of the tank out first, this way I would be able to avoid removing the metal trim piece at left hand side/top. No luck, the tank is a little bit too long for this to be possible.

Next step will be to get a price for refurbishing the tank and to source hoses to replace every hose in the trunk.

The Palm Kirby book describes how to get rid of the bulkhead fittings in the trunk corners, where feed/return lines pass through (page 237). I'm not sure I will do this. Any opinions on this subject ?


Trying to get right side out first:



Not possible



Out it is. Dark sections on the rear edge is made by me trying to use penetrating oil, but the part at the front left corner is probably fuel coming through pinholes.

 

Update and one question

Rust has been removed from the tank base.
It was actually tight, and the inside is according to the guy fixing it in really good condition.
New EFI clamps and modern fuel hoses are ordered. I ended up placing the order at Demon Tweeks, they had proper fuel hoses at fair prices and not least a fuel filler hose that should fit.
New closed cell neoprene to put under the tank was found on Ebay.

And to the question: I have read about a rivet in the body, that should protrude and potentially damage the bottom of tank. Where should I look for it ??

 

It is on the panel the tank sits on, and is one of the fixings that holds the pressed woodchip heat shield in place, the one above the rear axle. It can be drilled out and forgotten quite safely. It is towards the centre of the panel, clearly visible if it is still there.
Greg

 

I will say it's not there then, and it does not look like if it has been removed. Maybe this was not present in 1977 ?
I have 2 small 'buds' 2-3 mm high in the RH 45° rib in the body, visible on the photo as white points




Fuel lines are original, date marking from 1976. Actually nice to find evidence that the vintage is correct, many cars in Denmark is not quite as old in reality as on paper. This is done to reduce import tax, but it also reduces the value of the car when it actually gets old.

 

Did Jaguar ever fix the rivet problem in later cars? If they didn't can a metal shim be slipped under the tank to prevent the abrasion?
I also wonder if US Dept of Transportation? Requires a fix by manufacturer?

 

I have finished the job, and the smell has not returned during the first 10 mile drive with 25 liters in the tank. Tomorrow I will fill it and do a longer drive.

I have described the complete operation here: Fuel lines and tank @ XJ-S.DK

 

well i went a different route, NASCAR RACE polyproplyne fuel cell 20 US gallons.

also a HI output fuel pump with custom filter, and using all 1/2" dia. lines with hi pressure SS flex lines and AEROQUIP aircraft fittings!

and custom fuel rails and fittings!

all works fine for 22yrs, BUT i can still smell a slight fuel oder!

have checked many times but NO visable signs of wet fuel .

 

I still want to know which way round the taper mounting block goes. Someone must know. I don't trust the picture in jdht as correct

 

Ron, love that setup!

 

Just wanted to add my two cents to this topic.

I have had my trunk smell of fuel before. I have changed 3 fuel pumps and filters, had the tank leak and had it out for repair, and pulled the sending unit dozens of times to check fuel level.

I have had the carpet out for about a year and just re-glued it and re-installed it. My trunk hasn't smell of fuel in quite a while now. If its given time to air out, it can go away.

 

What is the purpose of the rivet? Is it present in a 1991 convertible XJS? If it is can it be eliminated? My car is being serviced and this is the time to address the fuel tank system completely.