AMC 20 filler plug stripped...Diff cover with filler plug?

[65reissue]

Hey guys...I have my fuel tank out so thought I would change my oil in the rear end today...AMC20 . While doing so I totally stripped out the filler plug in the axle. I used PB Blaster...let it set...now I can't get any grip inside the plug at all. Finally resorted to taking a chisel to it...no give...vise grips and it just rounds off. So...I am EXTREMELY frustrated and give out now...all over a filler plug. So...now I have decided to let the plug live there permanently and am in search of a differential cover that has a filler plug in it. Do you guys know of any? I found one that is a cast aluminum but around $170!!!! So...I'm at a loss now. Any help would be appreciated. thanks as always.

 

[Old Dog]

I don't know of any. although you could drill and tap one of the aftermarket ones I would think.

 

[IOPort51]

pull the rear cover and drain the oil. wrap the pinion bearing end with wet rags and apply DIRECT heat to the plug. when the plug is just short of red, push a candle into the threads. this should suck the paraffin into the threads and free the plug so you can pull it with the vice grips.

This is my very last resort but it has always worked for me.

I would suggest you apply a mixture of 50/ 50 acetone and automatic Transmission fluid and let it set over night before trying the heat.

 

[65reissue]

hey guys...thanks. I actually cooled off and went back out there and with some vice grips was able to get it on out...the PB Blaster probably had a little more time to work. Now...my new issue...the plug is completely destroyed as using in the future. I have heard of using some pipe plug from the hardware store...does anyone know what that might be? They said is basically a direct replacement. Any thoughts on this?

 

[IOPort51]

I think it.s a 1/2 inch pipe plug. Pipe threads are tapered, that's how they seal and they don't go all the way through. Brass is not as strong as the cast steel but it won't rust in. I think you should be able to find one with a 3/8" square hole in it that fits a socket wrench or a square headed plug.

hey guys...thanks. I actually cooled off and went back out there and with some vice grips was able to get it on out...the PB Blaster probably had a little more time to work. Now...my new issue...the plug is completely destroyed as using in the future. I have heard of using some pipe plug from the hardware store...does anyone know what that might be? They said is basically a direct replacement. Any thoughts on this?

 

[65reissue]

I think it.s a 1/2 inch pipe plug. Pipe threads are tapered, that's how they seal and they don't go all the way through. Brass is not as strong as the cast steel but it won't rust in. I think you should be able to find one with a 3/8" square hole in it that fits a socket wrench or a square headed plug.

Thanks alot...I will try to make to the hardware store tomorrow and see what I can find. Hadn't even thought about the Brass but that may be the best way to go. thanks again.

 

[wadeo5247]

just to throw my two cents in there had the same problem with my 76. the po messed up the plug I just welded a bolt in the hole or what was left anyways and had a wrench handy that fit the bolt, as soon as I finished welding it. stuck the wrench strait on it and it came right out. as for replacing it I just stuck a 1/2 inch plug (I believe) in place but with a sq hd sticking out now all I need is a crescent wrench to check oil....

 

[65reissue]

Thanks...I ended up going to Home Depot the other day and picked up a brass 1/2 plug with the square head sticking out. Like you say...easy now...just a crescent wrench needed. Regarding the plug that I was finally able to get out...it was aluminum! I know that that surely wouldn't have been factory...would it??? Thats why I was tearing the out of the thing. I would have been a little more gentle had I known that the plug was aluminum...but I stripped it...then chiseled it...finally with a lot of PB Blaster and vice grips...was able to get it out. Thanks again for all your help.

 

[Old Dog]

..it was aluminum! I know that that surely wouldn't have been factory...would it???.

I don't think so. Mines steel.
Glad to hear you got it fixed.