Removing transmission Drain Plugs, heat? Options

[Jon H.]

I have my transmission apart on the bench and I can't get the drain plug out? I'm not sure if I should use heat or not; out of fear of melting the case? What do you guys think? A little heat with the propane or get glowing with the oxy?

Thanks' Jon

[brant]

a little heat and a lot of heat are two different things
I played with some cut up cases and propane before
it did not ignite the magnesium mixture

I don't know if it would be safe or not to put an oxy torch to it
if it did ignite a magnesium fire you are in deep deep trouble.

it may be that the magnesium alloy of a case is safe and there is no risk...

but what if?


I've never had to use heat on over a dozen or so that I've played with
you should be able to get it with a correct wrench and some soaked in penetrating oil. Its an NPT type of thread pitch, so its probably just over tightened... try a breaker bar

[gus91326]

Impact wrench.

[Dr Evil]

I use up to MAP heat on them with no issue. I do not know about Oxy/acetylene, though.

I find that if heat does not work, I just drill a huge hole in the middle of the plug and use an easy out or other large rod with grippers. It comes out easy then. I have spare plugs if you need that are in perfect shape.

[SirAndy]

if it did ignite a magnesium fire you are in deep deep trouble

(IMG:style_emoticons/default/agree.gif)

[Dr Evil]

Even shavings of the case do not ignite well with MAP. I have tried to start parts of the case to see if I could with MAP, I could not.

[Jon H.]

Well I ended up using the impact and it came out. The threads were still good too.

Thanks for the help'

[Richard Casto]

I use up to MAP heat on them with no issue.

This seems to work for me nearly 100% of the time as well. I start with about 15-20 seconds of heat in a circular motion around the plug and then try to remove. It first attempt doesn't work, I repeat. It generally works on the first or second heat cycle.

Generally the ones that are problematic are those in which the plug has been chewed up by previous attempts to remove and the hex socket no longer fits very well.

Richard

[steuspeed]

On my first trans oil change I had to use my socket breaker bar. It's at least 2 feet long. There was well over 100 ftlbs on the drain plug. I bet the last guy used a impact gun to put it in. I think the spec is 15 ftlbs.

[Ian Stott]

I sprayed liquid wrench, tried it, no go. Did that every time (once a day at least) I walked by the tranny which was out on a bench, third day it came by hand, no power tools or breaker bars, no damage.

Ian Stott
Moncton
Canada

[ArtechnikA]

Well I ended up using the impact and it came out. The threads were still good too.

Now that it's out, you can consider using the 911 / 914.6 parts - external hex.
They're all tapered and do not require huge torque to effect a seal.
Anti-sieze is a good idea no matter which plug you use.

[Dr Evil]

I have not seen any of the external 911/914-6 plugs for sale. Do you know a source?

[ArtechnikA]

I have not seen any of the external 911/914-6 plugs for sale. Do you know a source?

Mine just came attached to the cars.
Always figured it was a dealer item.

Stoddard has a 999-064-020-02 magnetic drain plug for $16, which they say fits 519, 644, 716, and 741 transmissions - but they're the 356 specialists. That's the part number for 911 from the PET. No description tho.

Pelican has the same part number, but they do describe it as a 17mm internal hex, even though they show the same range of applications ('65-'89 911, 914).

Since it's a 999 number Porsche considered it 'general supply' so the 19mm external hex parts may just have been what was available off the shelf in the early '70's.

I expect there's a stash of them somewhere, possibly with someone who does a lot of 911 transmissions - Gary Fairbanks?

So - I didn't mean to set someone off on a wild goose chase, just thought it'd be a dealer item.