Threads for drain plug stripped.

Corrosion, Paint, Through Hulls, etc.
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DEnsign32
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Threads for drain plug stripped.

Post by DEnsign32 »

Greetings. Went to put my drain plug in for launch today and the threads inside hull are stripped. Would have to re tap but how do I go about getting an oversized stainless drain plug? Guy at the Marine store said I could drill out the threads and use rubber expanding drain plug?? Any knowledge of doing either would be greatly appreciated. 73, 32 foot sedan FB.
Thanks!
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Tuggle
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Re: Threads for drain plug stripped.

Post by Tuggle »

Don't think I would use a rubber expansion plug, measure your current stripped plug and go to the next size up. If it's 3/8 go to 1/2, Lowes-Home Depot both sell tap sets, drill bit and tap so there's no mistake. Aluminum is easy to tap, take your time.
"Deplorable", 1975 32' Express, Twin 318's, Raw Water Cooled, Lake Lanier, Ga.
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Tuggle
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Re: Threads for drain plug stripped.

Post by Tuggle »

Make sure you get an NPT tap, National Pipe Thread.
"Deplorable", 1975 32' Express, Twin 318's, Raw Water Cooled, Lake Lanier, Ga.
Fastjeff
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Re: Threads for drain plug stripped.

Post by Fastjeff »

My 19 footer used a 1/2 " NPT drain plug that required a wrench to install and remove. Screw that, I decided and went with a rubber plug. Since it leaked a bit I got out the old pencil grinder with a carbide bit and removed most of the threads. It now seals perfectly.

You might consider that solution (but don't tell anyone!)

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
DEnsign32
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Re: Threads for drain plug stripped.

Post by DEnsign32 »

The current plug is 3/4 inch diameter. The logical next size up would be 7/8 but they don’t seem to exist? Next size for tap and plug is 1inch. Going today to measure and see if there is enough material/space for a 1 inch plug...
Fastjeff
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Re: Threads for drain plug stripped.

Post by Fastjeff »

Wow! That's a pretty big tap.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington
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