Woe is me, gentlemen. Totally seized 69' XKE fuel sump cylinder

Gentlemen, I am experiencing the love which only a rusty jaguar owner can appreciate. I’m totally gutting out the interior and need to pull out my gas tank. Everything is free except for the fuel sump cylinder. It is absolutely seized with dry old gasoline varnish in the threads (i believe). When I drained it not a drop of gasoline came out. Only dry, black powder. So of course I turned the soft cheese like brass nut (used to remove the sump) into a perfectly round and shiny circle by applying way too much torque. I’ve used wrenches, sockets, ratches, strap wratches, adjustable channel locks. Gentlemen I hate to admit it, I even warmed it up with a blowtorch. God forgive me for that one, but she’s not coming out. I’m actually rocking the car front and back with how much tension I’m using trying to twist this thing. Righty tightly lefty loosie?

I sprayed wd40 on the outside, I’ve poured a fuel enzyme which “restores old gasoline” on hopes of liquefying or loosening any rock hard varnish. That will soak for 24 hours and I will try again. I know that using anything that has an open flame or sparks is absolutely stupid to use around a fuel tank. But in my desperation I have found that not even a blowtorch would end my suffering. So I remain confident that I might be able to drill 2 holes (with an extinguisher near by) and stick a piece of metal tubing through the cylinder and twist it off that way. But I know how this story ends. This will absolutely shred the ever loving jesus out of my sump cylinder and it won’t be repairable.

So I beseech you good people of the internet to help me figure out how I’m going to get this damned thing off without paying a professional. I promise I won’t use a blowtorch again.

Try a fallen or so of parra fin into the tank and leave to soak over days. Drain and repeat your actions minus the flame. Also liberally spray the thread area with a penetrant (WD 40). Best of luck.

Given what you have already done I am suprised the bottom of the tank has sheared off.

Gallon and paraffin.

So am I. I was positive it was going to break right off of the tank. I guess the tank isn’t as rusted to shit as I’ve been dreading. If I can’t find paraffin lamp oil locally could i use mineral spirits or something similar?

Edit: Thanks for all the replies, guys. I have it soaking in PB Blaster right now. I’ll spray more in the morning. Pretty dumb of me to not have gone for PB Blaster in the first place.

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At least give it a chance first with some proper penetrating oil. WD40 won’t do anything.

Just to be clear the righty tighty rule works when looking down on something but when upside down it can be confusing, you need to be turning it clockwise, handle of a wrench going left not right.

There are two possible agents bonding the threads, rust and shellac. If you leave old gas in carbs too long it’ll eventually flash off and the residue will stick up the float valves. Same goes for your sump threads. A good penetrating oil will free up rust but for shellac you’ll need to soak in carb cleaner.

Heat too? Likely. Be very careful.

I pulled my tank a couple of years ago as part of a fuel system overhaul. I don’t think it had ever been out, but mine is a rust free AZ car. Anyway I was also concerned about the sump cylinder removal. All I did was spray penetrating oil up from the bottom into the threads and let it sit for a few hours before I tried anything. It came off surprisingly easy. Even if you trash your sump they are relatively cheap to buy. Good luck.

Conflicting info here, anti clockwise for right hand thread…did this years ago on a 64 3.8 coupe that was four years old, the sump had rusted completely around its periphery and rotated straight out of the tank, thirty quid to replace it in those days I seem to recall…the piece of foam the tank sat on seemed to have trapped moisture causing the problem…


Yes something that doesn’t evaporate quickly and is thin enough to penetrate.

Best of luck


There is no hurry to get this tank out, mix ATF and acetone 1:1 , pour it in the tank so it will fill the sump and let it sit for a couple of days. Two or three times a day knock the sump with a hammer near the joint. after a couple of days use a large pipe wrench to remove the sump.
Since you mentioned a blow torch I have to add : make sure the car is well supported so it can not fall on you or anyone else. Good luck.

Regards, Joel.

I have sheared a tank before, rather than do that, an alternative approach (that is standard on some XJ saloons). drill & tap the brass, and fit a 9/16" head bolt with sealing washer

I have not tried this method yet for rusted on stuff since I just saw it a couple of months ago but I wonder if it might be possible and worth trying out for you

68 E-type FHC

I would also suggest to put pressure in both directions. Loosey lefty and then a bit righty tighty, loosey lefty and righty tighty until you have a little movement in order for the goop to penetrate the thread, let it stand for a while and try again. Once it gives try slightly larger arcs, back and forth until it is free.
Good luck

But seeing as he’s underneath the car Paul, he will have to turn it

If the car is on a solid stand and Mike is trying to remove the sump as he lays on the ground he still pulls or turns the sump to the left to remove it which is CCW as he looks at the sump from below.

Regards, Joel.

I’d think of it this way. Sitting behind the car, pipe wrench in hand, place the pipe wrench on the sump so the handle is pointing toward the center of the car. Pull the handle toward the rear of the car.

PB Blaster = Good Stuff!!!

I think this is at a point where I would give up any thought of salvaging the part. You say you have already rounded off the hex on the bottom.

One way to proceed would be (as you mentioned) drill a pair of holes in the thing with asomething like this:

Then either insert a length of pipe or a metal rod that would then accept a length of pipe to get enough leverage to move it.

I am somewhat surprised that the tank itself is tolerating this treatment as my recollection is that the thread engagement there is fairly shallow.

like I said, anticlockwise.