Stuck brass center-hull plug

[AZskidaddy]

Ok folks I've owned several ski boats over the past 30 years and have not had this happen, until now. I recently bought a 1993 Sport Nautique with low hours (<330) and in overall excellent shape. The previous owner had stored the boat 2 years earlier and left the plug in. I now am using the boat regularly and while the bilge pumps are doing their thing, I would still like to be able to drain the hull completely. I've used tons of liquid wrench and have "wrenched" on it as much as is possible in the awkward place that it's in, and it won't budge. I've considered torching it from the bottom but am concerned that when it expands from the heat it could damage the seal, fiberglass and gelcoat. Does anyone have any ideas?

[House324]

Try using a different penetrating oil named "Kroil". It works better than liquid wrench. Do not use a torch. It will damage the fiberglass. Apply it a couple times on the the threads from inside and outside and give it a couple days in warm weather.

[DanielC]

Another penetrating oil to use, acetone, and ATF, mixed 50/50.

You can also take a 9/16 box end wrench, or two of them if there is room, put the box end over one of the legs of the "T", and get more leverage that way.

[SkiTower]

You can also take a 9/16 box end wrench, or two of them if there is room, put the box end over one of the legs of the "T", and get more leverage that way.

sounds like a good way to break the handle off...

[shag]

PB Blaster....

[lucky7t]

This happened to my 03. I used mystic penetrating oil and stuck a wrench on it and lightly tapped with hammer. It came loose but scared me. I put anti seize on it after.

[AirTool]

Sometimes my plug is hard to get off when I have the bow turnbuckle down tight. Seems impossible but I'm pretty sure of it. you might mess around with the tongue/jack or maybe try to break it loose backed down in the water - don't take it out of course.

I would think the final draw would be to start drilling it out from below. Start with a small bit (make sure you are in the center) and work your way up. Use a right hand bit. The friction might break it loose and it will unscres. Eventually, you could then chisel it out or if the hole would pass a small saw blade, cut through it on each side and it will fall out. I had to do that on a heater fitting on my chevy truck. they cease up so you carefully cut it into two halves and it falls out - amazing.

[AirTool]

I would think the final draw would be to start drilling it out from below. Start with a small bit (make sure you are in the center) and work your way up. Use a right hand bit. The friction might break it loose and it will unscres. Eventually, you could then chisel it out or if the hole would pass a small saw blade, cut through it on each side and it will fall out. I had to do that on a heater fitting on my chevy truck. they cease up so you carefully cut it into two halves and it falls out - amazing.

If you get to a point you want to try this - we can talk by phone first. See post above for trailer/tongue position.

[DanielC]

"sounds like a good way to break the handle off... "
That is a possibility.
So is the possibility it will just unscrew.
How do you know until you try?

[TxJole]

T handle water meter key.

[Mahoo]

How about removing the entire through hull fitting and then get the plug out on the shop bench? The through hull should be easy to remove.

[bhectus]

Sometimes my plug is hard to get off when I have the bow turnbuckle down tight. Seems impossible but I'm pretty sure of it. you might mess around with the tongue/jack or maybe try to break it loose backed down in the water - don't take it out of course.

I would think the final draw would be to start drilling it out from below. Start with a small bit (make sure you are in the center) and work your way up. Use a right hand bit. The friction might break it loose and it will unscres. Eventually, you could then chisel it out or if the hole would pass a small saw blade, cut through it on each side and it will fall out. I had to do that on a heater fitting on my chevy truck. they cease up so you carefully cut it into two halves and it falls out - amazing.

I'm just failing to see what the bow turnbuckle has to do with the drain plug on the bottom of his boat. Also, before drilling out the plug, and potentially ruining the housing, I would just pull the housing like suggested, and then re-install with a new bed of 5200 once the old stuff is scraped out.

[AirTool]

I'm just failing to see what the bow turnbuckle has to do with the drain plug on the bottom of his boat. Also, before drilling out the plug, and potentially ruining the housing, I would just pull the housing like suggested, and then re-install with a new bed of 5200 once the old stuff is scraped out.

I said it seems impossible. I've noticed if I pull my plug out while the boat is on the ramp, it comes right out. If I do it when I get back to the barn and the bow is pulled down tight, the plug is almost impossible to get out by hand especially if I put the plug in pretty tight. I used to crank the **** out of the plug when I first got the boat but I've learned that is not necessary. If I did crank it super tight by hand then try to pull the plug with the bow cinched down, it was tough and I might even need a cheater. I can usually get it out now by hand if I didn't overtighten it. In either case, if I pulled it out on the ramp there was no problem.

Here is what happens: 196s and 206s rock forward and aft on the wishbone trailers and these boats are fairly flexible. The brass thru hull has relatively no strength at all. So if you pull down hard on the front as the turnbuckle is designed to do, that puts a compressive load on the bow and somewhat compresses the through hull which is about where the boats naval would be.

I couldn't tell what boat the op had. The problem I experience would be less on a v-drive which I think is what you have.

On the drilling, it would be simple for anyone with mechanical skills to drill out the plug w/no damage to the thru hull. Besides, why pull out the trough hull if you haven't ruined it yet. The drilling question would be if you could get to it or the trailer would be in the way.

[bhectus]

The explanation in your case of why it was easier at the ramp is the moisture still around the threads is acting as somewhat of a lubricant. By the time you get home it is dried out and harder to remove. The plugs have a "tapered" thread which helps act as the sealing mechanism, there is no need to hulk them down super tight. There will be more water coming in to the bilge from the prop shaft packing gland anyway. It's not the end of the world to have a little water in the bilge. The packing gland on the older boats was designed to leak some, that is the cooling mechanism.

Anyways, back on topic for the OP - The ATF blend of lube that someone mentioned already, or Kroil would be your best bet. Then put a pair of channel locks on the t-handle and have a buddy lightly tap the top of the t-handle with a hammer while you try and twist it out. That will function similar to what an impact wrench does and hopefully help break it free.

[shag]

I would find it hard to believe that the hull of any boat, would flex enough to compress a fairly stout through hull fitting.... Except maybe an old bayliner.... I remember pushing one off the beach one time (the jack*** ran aground) and the side pushed in like a good six inches to a foot, then popped back out like a plastic bottle..... Guess it was good they were all wearing the orange PFD's) lol