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Good afternoon, gents

It's oil change time for my 7-45 but I am having difficulty getting the sump plug out of the crank case.

The plug is a 3/4" AF square-head affair - the same as the fill and drains on the gearbox and the filler on the steering box.

Its on really tight and 3/4 open end spanners wont work as they will only round-off the head.

Can anyone tell me whether there was originally a specific square socket or spanner for this job or if there is a good modern tool available

Thanks

Normally just a 3/4 inch open-end wrench works just fine, apparently yours is especially tight, you may have to resort to a pipe wrench. I hope the threads won't be stripped in the oil pan! Newly manufactured plugs with copper gasket are available from Byron York (York Restorations) up in CT.

Thanks Dave.

I've tried the pipe wrench approach but it just slips off.

I'm looking at getting a 3/4 female to 1" male socket adaptor and grinding it flat on the bottom so as to get a nice flush fit with the plug (i.e. remove the internal chamfer)

Then attack it with a 1" spanner.

What do you think?

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Ken,

This is a pretty drastic technique, but I have used it successfully on an old tractor with a similar drain plug:

1) Drill (slowly) and tap the plug for a 7/16" REVERSE thread bolt
2) Insert 7/16" x 1" REVERSE thread bolt and washer and tighten.
3) Keep tightening bolt until the plug comes loose.

If you drilled slowly, all the metal bits should come out with the oil.

Oh, and it's a bit messy as you are taping while oil is pouring out of the hole you just made.

Again, drastic and you need to find reverse threaded tap and bolt.

Tom

Tom, that's a very clever approach! Certainly purchasing a left-hand tap is quite easy but for the bolt you might have to buy a box of 25 or so just to get 1 if you can't make it yourself. Nevertheless it's a good potential solution.

Owens suggestion for a pipe wrench ought to work.
If it has to be drilled and tapped then why not just drill and tap it for a some standard thread size and install a bolt or plug as a NEW drain plug??? Of course it won't be Hoyle for originality if that's an issue for the drain plug.

Another option is to use a pump to pump the oil out thru dip stick hole of some other convenient place. Oil needs to be warm. I've never used a pump but many have used it for motorcycle applications (seperate tank of course) and other applications wehere access to draining oil is difficult.

If all you really wanted was an alternative way to drain the oil, you could just loosen the small access cover under the oil pump screen - it's also at the lowest point in the pan.

KT:
Have u formerly removed the plug yourself at your own hand???

If not then perhaps some previous mechanic used locktite on the threads. Loctite is often used as a make shift sealer. And it does an excellent job it. If the pipe wrench won;t budge it then look closely for any signs of a sealer around the threads, blue or red.

IF loctite has been used then it mite be necessary to heat the plug wich a torch to melt the loctite. Howeerver since i am not familiar with this particular set up the torch may or maynot be advisable.

Thanks for all your suggestions chaps. All seem to be valid.

After work I will have another go.

Watch this space

Still can't shift it!

I heated the casing up to no avail.

I got a real good grip of it with the mole grips (not sure what you guys call them) but they only started to deform the cap.

I'll leave it for now and get myself the adaptor I referred to earlier. If that fails, I might drill it out and insert a bolt but that it really not the originality that I'm looking for.

Alternatively I can drain the oil via the pump access plate and them drop the pan and take it to a specialist to get the plug removed.

Happy days