Removal of stuck, or tight, leaking Oil Pressure sendor on V12

Hello all - I have read through past postings, and seems that others have had a problem of removing the Oil Pressure sendor (the large round can type) located at the rear of the V12 - trying to do this on my 1991 XJS V12 Classic Collection Coupe - I did find a YouTube video where the person broke the Oil Pressure sendor mounting section below the sendor - therefore I do not want to apply too much pressure on mine and break the mounting section - I have tried using an 18mm crowsfoot (seems to fit best), but just could not budge, or turn loose, the sendor (did not find any way to get a clear enough space to use a spanner) - as per Greg’s (poster gregma) suggestion, I did unbolt the throttle capstain (top part only, leaving everything still connected - throttle butterfly rods, accelerator cable, kickdown switch and ECU switch) from the pedestal, and also moved the top coil forward a bit, to gain some working room - I was thinking of unbolting the Oil Pressure mounting fixture part, which has the Oil Pressure sendor, and the Oil Pressure light sensor - this looks like I will also have to unbolt the banjo fitting on the side (I am thinking that this is what was mentioned in Kirby Palm’s “Experience in a Book” but not quite sure) - then I think I can remove the mounting part, so I can remove the sendor and the sensor on the work bench with less chance of breaking the mounting base - appreciate any suggestions - thanks, Tex - sent 10/7/2021 2354hrs. EST USA.

EDIT - pictures added of throttle capstain partial removal and Oil Pressure sendor wet with the oil from leaking through the sendor - Tex

Your plan is best method to avoid damage, be careful not to twist the banjo line.

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Thanks Robert - will proceed with caution - Tex.

Yes, I remember mine was quite difficult too. Just keep soaking it with PB Blaster, maybe overnight, and maybe even a few taps with a hammer (or use long extension to tap on) to help break it free.

I don’t think you should unbolt the mounting fixture, as that is giving some good resistance instead of the oil lines.

Also, sometimes it helps to actually try to tighten it a little, and then loosen.

Thanks Greg - will try PB Blaster before removing anything else - I just added some pictures to my first post of the OP sender (did not come through before) in case it will help others - Tex.

I have never understood how PB Blaster is supposed to help when the item is a sealed joint. It can’t get in there, can it? Doesn’t this thing have an O-ring in it or something? Perhaps a copper sealing washer?

nope, it simply uses tapered pipe threads, if I remember right.

And anybody trying to remove plug on drivers side (opposite idiot light oil sender) it was so corroded I stripped it. Don’t know why they put simple screwdriver slot in there. I finally managed to unscrew with hammer/chisel.

Very happy to put in my own electric oil pressure sender there. Amazing how inaccurate the oem sender readings are.

And they are US NPT threads on my 1988. Originally i thought they would be British npt, so bought adapter. Leaked. Put US npt threaded sender in there, leak free.

I noticed that plug, with the slot in it, located, as you stated, on the B bank side of the Oil Pressure sender, and Oil Pressure light sensor, mounting bracket - wondered what the purpose of that position on the bracket was intended for.

I don’t know what the original intent of the plug was, possibly for a service gauge to confirm oil pressure. That is where I plumbed in my mechanical oil pressure gauge. To extract the plug, it took a long giant square shank craftsman screwdriver, with me leaning on it with all my weight to keep it in the slot, while my wife applied the twisting force with a big crescent wrench on the screwdriver shank (cuz it’s square) just below the handle. It took a lot of force to break it loose.

I have had to use the very same method for removal of such type screw in the past - always needed a helper.

Is there room for an impact driver in there, the type you strike with a hammer.

Not in my opinion - that is, without removing more items - also, might be concerned that the bracket may not take too well to that extra force/vibration and crack - not sure how, or why, the bracket cracked in the YouTube video I looked at, where the fellow showed how his bracket was broken during the attempt to remove the OP sendor.

In my old tool box, I have an impact screw driver. Set the direction, CW or CCW and place the blade in the head. Whack the top with a hammer. Most fasteners succomb !!! .

III did not see the post. I have one in my old tool box.

I removed mine on my 95 6.0 liter using crows foot and 12 inch extension. I do not recall it being a big problem. Might have tapped gently on socket handle. The specified torque for that thing is only about 20 to 27 NM.

Hello Jim - that is the exact setup I started using, but have not gotten loose yet - to get the crows foot to go all the way on to the “nut” section of the stem of the OP sendor, I have the drive tongue coming in from the bottom, since when the drive is on top, the crows foot does not go all the way on to the “nut” section - this entailed using a drive handle that was able to flip at a 90 degree position, then used tape to make sure the drive tongue did not fall out of the hole in the crows foot - I will be trying again to move it on Monday morning since work has commanded my time over the weekend - letting it soak as suggested by Greg.

Another thing to try. … since you don’t care about old sender, use channel lock pliers on it, may be enough to turn. And if it snaps off, who cares. Maybe then a socket will fit?

Dang, I would think the post-facelifts would not be problematic :confused: … Guess I’ll find out for myself with Superblack if and when I ever need to replace hers. :crossed_fingers:

Or that plumbers tool someone mentioned. Too thick to fit onto Hexnut bottom of the sender. But may fit onto and bite into the body of the sender.
But my solution was with the crows foot. And as Tex said, turned over so the ramped up thickness is diwn