Drippy drain plugs

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Chris P
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Drippy drain plugs

Post by Chris P »

The drain plugs on both my transmission and transfer case leak. Can anyone recommend a thread sealer? Would standard plumbers thread tape work?

thanks
Chris P
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w30bob
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Re: Drippy drain plugs

Post by w30bob »

Hi Chris,

Not sure what plumber's thread tape is........do you mean the white Teflon tape? I'd think the yellow Teflon tape would work better with petroleum products. Locktite would also work, but you have to let it dry.......which means you have to drain the oil out first.

But I thought old Army trucks and Harleys were SUPPOSED to leak! :shock:

regards,
bob
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Re: Drippy drain plugs

Post by nhjohnny1 »

I have a buddy in HVAC, he has a product called gasoila that is a pipe paste for black iron oil fill pipes and the like. I have used it on my drain plugs with good results.
Chris P
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Re: Drippy drain plugs

Post by Chris P »

Thanks!
Chris P
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Re: Drippy drain plugs

Post by MSeriesRebuild »

Numerous products exist, we have used many different ones. What we have found to work best is Lock-tite brand thread sealant for hydraulic fittings. How you apply it makes all the difference in the world too. What we do is drain the oil completely. Use a clean container with a cover if the oil is to be reused. When draining is complete, thoroughly clean the threads on the plug and in the case with brake cleaner or equivalent solvent, blow dry completely. Apply the sealer into the dry threads in the case, smoothing with your finger tip, and on the plug. Screw the plug into the case finger tight, then immediately torque to *25 ft. lbs. ONLY*. To much torque will force the sealer out of the tapered NPT threads, result, you will likely still have a drip. It is best to allow the newly sealed plug to sit over night (or at least a few hours) before refilling with oil. We very seldom have any dripping issues if a clean, undamaged plug is sealed and installed this way. TIP: be sure to inspect the drain hole area well in and around the threads of the case after cleaning; we do see a few that have been over-torqued to the extreme, with the result being a cracked case. In the event this is what you find, a good repair of the cracked area will be necessary before the leak can be stopped. In these cases, what we usually do is "V" out the cracked area, braze it up solidly, replenish good threads, apply sealer, install plug, and torque it to 25#.
Charles Talbert
www.mseriesrebuild.com
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