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My oil drain plug is stripped I believe it is 1/2 x20 on my 95 so does anyone one know what the next bigger size would be if I was to drill it and tap it? seems like every thing I touch lately turns to sh#t
My oil drain plug is stripped I believe it is 1/2 x20 on my 95 so does anyone one know what the next bigger size would be if I was to drill it and tap it? seems like every thing I touch lately turns to sh#t
Most of your parts stores have single / double oversized plugs, in the help / Motormite section.
Last edited by THE 383 admiral; 12-18-2014 at 08:30 PM.
Most of the parts store self-tapping drain plugs are a short term fix. If the pan threads are really messed up, the self-tapping plug may not thread correctly and provide a good seal much less a new set of threads that will work for more than 2-3 more oil changes.
It may be worth the time and effort to drop the pan and have the hole re-threaded and a new plug installed.
Back on the road if anyone else has to do this job with the oil pan on the car there is not enough room for the T tap handle that holds the tap so I used a 3/8 deep socket and small extension to hold the tap getting it started straight was a little tricky but can be done.
Well it lasted a couple oil changes but its stripped again I just orders a Drain Plug Size 1/2"-20 double oversize piggy-back self tapping Id that doesn't work time to change the oil pan. does anyone know what size a double oversize 1/2"-20 would be? that way I could drill and tap it first?
Well it lasted a couple oil changes but its stripped again I just orders a Drain Plug Size 1/2"-20 double oversize piggy-back self tapping Id that doesn't work time to change the oil pan. does anyone know what size a double oversize 1/2"-20 would be? that way I could drill and tap it first?
I came up with
5/8-18 not sure if that is correct?
The OS plugs aren't generally meant to be used with a tap. Did you actually check the thread with a screw pitch gage or you assumed or what?
Somewhere either in production OR only service pans the plug was changed to an M12 X1.75, SPO cataloging is very vague regarding. Most mention the 1/2 -20 being there but it sees it ain't "gospel".
I wouldn't dick with it. Measure to see what can be accommodated and drill/tap for a known dimensionaly correct plug. I'd think maybe that a heli-coil or even a Time-sert might seep, I realize it's going to be gasketed but still........
Count the number of threads in the pan and see what can be done. I'd think Time-sert because it's flanged to be seated.
See the notes here regarding using a Time-sert if a "tin pan" has had an OS plug used:
Yea I checked the oversize plug by matching it with the correct nut that would thread on all the way I used a tape because I was afraid the os plug wouldn't cut into the steel oil pan enough.
How come you cant Heli-coil it and use the original size drain plug ?
I don't see why you would need to replace the pan if the OS plugs don't work when you can heli-coil it. Although if it was me I would pull the pan off before you drill, tap and heli-coil the drain plug hole, since you don't want any metal shavings getting left in the pan.
12-18-2014, 07:45 PM
Stripped drain plug ?
if anyone else has to do this job with the oil pan on the car there is not enough room for the T tap handle that holds the tap so I used a 3/8 deep socket and small extension to hold the tap getting it started straight was a little tricky but can be done.
