Gearbox Oil filler/level plug

[Alec Dawe]

Thought it would be a good idea to check the gearbox oil level today. (240GLT M47 box)
However, not so good to find that someone had butchered the oil filler/level plug. It has no hexagon to speak of, faint signs that there might have been a hex there at some time. Tried hammering the tightest socket I could on, but no joy, just rounds off. Tried, the awful mole grips, no joy, tried even the old real butchers trick with hammer and blunt chisel to try to shock it round. Still no joy.

Anyone have any ideas, apart from welding a bar on the remains?
Can you get new plugs?

Alec

[ivor940]

Hi Alex. If you have a gas blow lamp ( and no fuel leaks ), try slightly heating the aluminium gearbox area around the filler plug. As aluminium has a greater coeficient of expansion than the steel plug, the plug should loosen when the aluminium is hot. If I recall someone mentioned before about always checking the fill plug on a gearbox is checked for looseness before draining the oil out. Hope you are sucessful. If you need it and it will fit, I can send you a fill plug from a '92 4 speed + O/D gearbox ( just e-mail me with snail mail address)

ivor940

[Glen Morangie]

Depending on how much is still exposed - can you get a pipe wrench on it, also referred to as a 'stillson wrench' IIRC, these tighten as angular force is applied, and have sharp teeth in the jaws to bite into whatever it is they are applied to.

They will chew up any thread on the plug but it sounds like you are down to 'last resorts' and will replace the plug anyway.

[Alec Dawe]

Tried that too, gave up before I chewed everything off the plug and had nothing left to weld a bar to!!

Will get a mate to weld something on the dying remains of the plug tomorrow I hope!

[morsing]

Surely a pipe wrench will get it off?! Still nothing I've come across that a pipe wrench couldn't get off. I even use it on brake lines

[Clifford Pope]

On rounded-off nuts etc I've often found it a good idea to stop and file or grind some new flats, to take a smaller size spanner or a wrench. Filler plugs often have quite a lot of thread protruding from the casing, with the squared off bit just a pimple on the end. if you file two parallel flats well into the threaded section, can't you use a hefty wrench on that?

[Alec Dawe]

Originally Posted by Clifford Pope

On rounded-off nuts etc I've often found it a good idea to stop and file or grind some new flats, to take a smaller size spanner or a wrench. Filler plugs often have quite a lot of thread protruding from the casing, with the squared off bit just a pimple on the end. if you file two parallel flats well into the threaded section, can't you use a hefty wrench on that?

Problem is that this is a collared plug, not the usual threaded sort. Hex top, collar with washer/seal underneath, then the threaded bit. If it had thread stickling out, I'd just butcher it with a stillson, but being collared, I dont want to damage the mating face on the gearbox.
Will wait for my tame welder to weld a bar on the remains, see if that shifts it!

I had enough of drilling wasted studs out of steam valves this weekend, then retapping the holes. Pah! Thought I was going to have to resort to putting a stepped stud in at one point, but found just enough sound metal to get a decent thread by drilling a bit deeper! Now to see if it leaks, next weekend!