Damn....Just trashed Diff fill plug
Thread Starter
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 492
From: Salmon Arm, BC
Damn....Just trashed Diff fill plug
I just spent all day trying to get the plug out to refill the diff. I totally F'ed the plug...Had a 18" breaking bar on it, and I was hanging on the end of that...plug wont budge
. Eventually I rounded off the square plug, and then nothing would grab. Tried welding a nut on but the cast just shattered after a slight pull. Tried to use the air chisel, but that just broke chunks off the plug. As all the fluid drained out while changing the pinion seal it looks like I'm going to have to pull the diff out to fix this
.....any other ideas I might try???
. Eventually I rounded off the square plug, and then nothing would grab. Tried welding a nut on but the cast just shattered after a slight pull. Tried to use the air chisel, but that just broke chunks off the plug. As all the fluid drained out while changing the pinion seal it looks like I'm going to have to pull the diff out to fix this.....any other ideas I might try???
Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,986
From: Connecticut, USA
I see you have a 77 so that has a cast iron diff with 3/4 npt threaded fill hole.If there is now a hole in the plug, try some heat around the OD of the plug, then use a 3/4 npt "easy out" if you have one. If not grind up a tapered wedge to fit in the hole and try to back it out.
Thread Starter
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 492
From: Salmon Arm, BC
Thanks Gary, That was my next approach, but since the diff is covered in oil I'd like to clean it up before approaching with an open flame. The plug dosn't have a hole in it yet....but I'll soon fix that
Thread Starter
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 492
From: Salmon Arm, BC
Ya....I got the righty/lefty thing figured out....nothing left to grab with the pipe wrench (tried that)....so I spent all day pulling the diff out, got the cover off and Its in the vice awaiting the torch
Found some more problems whil I was in the diff.....end play on the yolks .080" left, and .120" right. The right one is almost worn to the clip. I think new yolks are in order, and I'm going to have to cut the shock mounts to get my totally wornout strut rods off. The good news is if ever I have to remove this stuff again, it'll be a snap
Found some more problems whil I was in the diff.....end play on the yolks .080" left, and .120" right. The right one is almost worn to the clip. I think new yolks are in order, and I'm going to have to cut the shock mounts to get my totally wornout strut rods off. The good news is if ever I have to remove this stuff again, it'll be a snap
Le Mans Master
Joined: Jan 2006
Posts: 6,506
Likes: 139
From: Butler Pa
In the future, the best way to remove a plug like this is to take a torch and heat the plug only until it's red hot. Let it cool and it'll come right out.
What happens is the plug expands much more than whatever it's screwed into and breaks the threads loose.
What happens is the plug expands much more than whatever it's screwed into and breaks the threads loose.
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Tech Contributor
Joined: Aug 1999
Posts: 15,175
Likes: 3,986
From: Connecticut, USA
Ya....I got the righty/lefty thing figured out....nothing left to grab with the pipe wrench (tried that)....so I spent all day pulling the diff out, got the cover off and Its in the vice awaiting the torch
Found some more problems whil I was in the diff.....end play on the yolks .080" left, and .120" right. The right one is almost worn to the clip. I think new yolks are in order, and I'm going to have to cut the shock mounts to get my totally wornout strut rods off. The good news is if ever I have to remove this stuff again, it'll be a snap
Found some more problems whil I was in the diff.....end play on the yolks .080" left, and .120" right. The right one is almost worn to the clip. I think new yolks are in order, and I'm going to have to cut the shock mounts to get my totally wornout strut rods off. The good news is if ever I have to remove this stuff again, it'll be a snap
but seeing as you rounded yours off... i donno what would work there :S
Le Mans Master
Joined: Jun 2005
Posts: 5,447
Likes: 3
From: Syracuse NY
I trashed mine with a friggin pipe wrench trying to get the posi tag off for a member having his 68 judged. A torch would destroy the plastic tag. Anybody got any ideas?
Sorry for the hijack.
Sorry for the hijack.
Thread Starter
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 492
From: Salmon Arm, BC
well I finally got the damn plug out. I tried heating around the plug, and heating the plug only with no luck. I decided to drill out as much as I could and get in there with an assortment of chisels and beat the living daylights out of what was left of the plug. Once I got a small chunk of the plug removed the rest came out really easy.....I just can't figure what was holding in in so tight....I thought it may have been rusted in but it wasn't. Now all I have to do is get a 3/4" npt tap to fix up a few of the threads I damaged
Team Owner
Joined: Mar 2002
Posts: 24,160
Likes: 78
It doesn't take much corrosion to bind up those NPT fittings. Some advise against it, but I put a light smear of wheel grease on the plug threads.
