Threaded Transom Drain Plug

[Bob&Jilly]

The square drain bolt on my transom is very tight and will not turn with a normal wrench. I am concerned about stripping the bedding. Any suggestions on how I might remove it?

 

[Pandion]

The square drain bolt on my transom is very tight and will not turn with a normal wrench.

I had that happen a couple of times on our '21 R27. I got the plug out by applying heat from a heat gun (with a narrow nozzle) directly to the plug.

Now, I use a bronze plug (instead of the more-common brass) and apply thread sealant to the plug. Tighten until snug and I've not had any issue getting it out.

 

[Bob&Jilly]

I had that happen a couple of times on our '21 R27. I got the plug out by applying heat from a heat gun (with a narrow nozzle) directly to the plug.

Now, I use a bronze plug (instead of the more-common brass) and apply thread sealant to the plug. Tighten until snug and I've not had any issue getting it out.

Thanks, it had a very small rod about 3/8th of an inch long from the mid point which immediately sheared off.

 

[OverTime]

I had that happen a couple of times on our '21 R27. I got the plug out by applying heat from a heat gun (with a narrow nozzle) directly to the plug.

Now, I use a bronze plug (instead of the more-common brass) and apply thread sealant to the plug. Tighten until snug and I've not had any issue getting it out.

Putting heat directly on the plug might actually expand it, making it tighter. I've had good results heating the area AROUND the plug, expanding that and it loosens the plug. I always use thread lube (anti-seize) not sealant and just snug it up good, not gorilla tight.

 

[SeaCabin]

Mine got stuck….wouldn’t even budge with a light impact wrench. Rather than destroy everything by muscling it out, I just removed the screws holding the whole fitting, and replaced it….with plenty of 4200. Make sure the new fitting has the same screw pattern. Now I coat the threads with 2-4-C grease and just snug it tight. While you’re at it, if you’ve got a pod, loosen its drain screw and coat it too.

 

[Bob&Jilly]

Mine got stuck….wouldn’t even budge with a light impact wrench. Rather than destroy everything by muscling it out, I just removed the screws holding the whole fitting, and replaced it….with plenty of 4200. Make sure the new fitting has the same screw pattern. Now I coat the threads with 2-4-C grease and just snug it tight. While you’re at it, if you’ve got a pod, loosen its drain screw and coat it too.

Thanks, I am a bit confused. What did you remove? There are three screws holding the plate, is that it?

 

[SeaCabin]

Thanks, I am a bit confused. What did you remove? There are three screws holding the plate, is that it?

Yes

 

[Bob&Jilly]

At this time I have tried heating, impact tool, liquid wrench and still will not move.

 

[Bob&Jilly]

Mine got stuck….wouldn’t even budge with a light impact wrench. Rather than destroy everything by muscling it out, I just removed the screws holding the whole fitting, and replaced it….with plenty of 4200. Make sure the new fitting has the same screw pattern. Now I coat the threads with 2-4-C grease and just snug it tight. While you’re at it, if you’ve got a pod, loosen its drain screw and coat it too.

where did you get the replacement and how did you remove the old one? thanks

 

[ohioan55]

The square drain bolt on my transom is very tight and will not turn with a normal wrench. I am concerned about stripping the bedding. Any suggestions on how I might remove it?

Once you get it out, like said, use the bronze. But, a common thing used to keep threads from seizing in a marine environment is anti seize lubricant. A tube can be had from just about any auto parts store. I keep a tube on hand..

PS, another thing used in many shipyards for stuck stuff is wintergreen oil. Apply it first, then heat like mentioned above.

 

[SeaCabin]

I would remove the 3 (or 4) screws and then knock it out with a drift from the bilge area if stuck. If you can’t find a matching screw pattern replacement, once out you could reattach it to a piece of metal or wood with screws/bolts whatever and put some muscle on the square end, or possibly put the square end in a vice and try a pipe wrench on the flange. Note, this risks damaging the flange. Or drill it out, or take it to a machine shop.

I don’t recall where I got the replacement but I did go to the next size up screw when putting it back, along with 4200.

 

[John Cortesy]

You should try PB Blaster. Find it at the auto parts store. It will loosen the gunk holding the threads together. Spray it on the threads from both the inside and the outside. Give it time to work. That stuff is amazing.

 

[n8baller01]

After I got mine to budge last year with a liberal amount of PB Blaster and a bit of back and forth (tighten/loosen), I purchased a non-metallic "marine" grade anti seize. I was able to hand tighten, and then used a crescent to move further a quarter turn. Came out this year no problem! Found the little 2oz jar on Amazon.

 

[OverTime]

I've been using anti-seize in the steam fitting trade for 50 years. The first time is the hardest! 😀

 

[Bob&Jilly]

You should try PB Blaster. Find it at the auto parts store. It will loosen the gunk holding the threads together. Spray it on the threads from both the inside and the outside. Give it time to work. That stuff is amazing.

Thanks, I have been using Liquid Wrench, is there a difference?

 

[OverTime]

PB Blaster comes in a spray can with a long nozzle. It works pretty good.