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TR2/3/3A Leaking Gearbox drain plug.......
- Thread starter karls59tr
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that is a 3/8 pipe thread, it wouldn't hurt to try to chase. I use Teflon tape on all such threads.
TR3driver
Great Pumpkin - R.I.P
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Do they even make thread chasers for internal tapered threads? Don't recall ever seeing such.
My first step would be to liberally lubricate the plug with teflon pipe dope (which is what I also use as 'sealer'), and put it in straight. If you can get it started straight, it should take care of the cross threading.
If that doesn't do, I'd try tapping it just a bit deeper with an ordinary NPT tap, preferably an old one. But don't go too deep, as it is possible to cut the hole oversize until the plug won't fit.
If that won't work or you don't have a suitable tap, check your FLAPS for a "repair" drain plug with oversize, self-tapping threads. Unfortunately it becomes a permanent bodge until you can get it apart and install a Helicoil or have the hole welded up and redrilled.
Oops, ignore that last bit. Apparently no one has them in 3/8 NPT. Just buy the tap, it should be readily available. You'll need a tap handle or socket and T-bar to fit it as well.
My first step would be to liberally lubricate the plug with teflon pipe dope (which is what I also use as 'sealer'), and put it in straight. If you can get it started straight, it should take care of the cross threading.
If that doesn't do, I'd try tapping it just a bit deeper with an ordinary NPT tap, preferably an old one. But don't go too deep, as it is possible to cut the hole oversize until the plug won't fit.
If that won't work or you don't have a suitable tap, check your FLAPS for a "repair" drain plug with oversize, self-tapping threads. Unfortunately it becomes a permanent bodge until you can get it apart and install a Helicoil or have the hole welded up and redrilled.
Oops, ignore that last bit. Apparently no one has them in 3/8 NPT. Just buy the tap, it should be readily available. You'll need a tap handle or socket and T-bar to fit it as well.
M
Member 10617
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Randall recommends Teflon pipe dope. Probably best. But if you use Teflon tape, be sure not to use the plumbers' version of the tape. Use the Teflon tape you can purchase at auto supply stores. It is specially made for this use. It resists oil and gasoline.
vivdownunder
Jedi Warrior
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Loctite 565 is a sealant option for tapered threads. The risk with teflon tape is to an overdrive. A loose strand could get past the filter and into the gubbins.
Viv.
Viv.
The only thing I might add besides the sealer recommendations is clean and take a good look at the threads.Flashlight and magnifier if your eyes are like mine.If its only cross treaded on the first thread I have used angled lathe tools to scrape the thread .If you retap try to get the tap started straight by hand.Tom