Freeze Plug Options

[kwoolard]

During the winterizing of my boat a couple of weeks ago, I apparently didn't get all of the water out of the block and a freeze plug pushed out. Hopefully that was all that was done. I realized after noticing the freeze plug was out, that I had some rust blocking my drain tap on that side not allowing the water to exit. Anyway, the freeze plug is located right behind the engine mount. Is there any type of expandable freeze plug I can put in its place, or does my engine have to come out?

 

[WillyBWright]

Re: Freeze Plug Options

You don't have to pull the motor if you can get a swing on the new plug with the motor mount removed. You just have to hang the motor to take the weight off and remove the mount for access. There are rubber expandable plugs available at an auto parts store, but hardware will be galvanized and decay in a boat motor. Best off using a marine brass replacement. If you can't get a swing to pound it in, the other optioon would probably last a few years, but failure underway wouldn't be a good thing.

 

[Don S]

Re: Freeze Plug Options

You might want to put in one of the expandable type since it's real easy, then pressure check the cooling system to be sure the block didn't crack also. Those are core plugs and not Freeze plugs as they are so often called. I have seen many an cracked block that didn't pop a core plug when it froze.

 

[kwoolard]

Re: Freeze Plug Options

I picked up one of those expandable plugs today. I'll try it out tomorrow. Don you're starting to scare me about the cracked block possibility I guess those plugs aren't designed to push out when the block freezes?

 

[olbuddyjack]

Re: Freeze Plug Options

Thats not their purpose even though thats what often happens. The holes are there to remove the sand after casting the block. The plugs are just a cheap easy way to seal up the holes. If your water jacket wasn't clear full you may have got lucky. I hope it goes your way.

 

[kwoolard]

Re: Freeze Plug Options

I think I may have got lucky this time. I installed one of those rubber expansion plugs. It went well considering I had to remove the starboard engine mount, which had engine mount studs rusted away. Took the boat out for a 30 minute ride, engine started and ran great, oil pressure and temperature were good. Come back in and checked the oil, and it had no signs of water. I assume if I had cracked the block or a cylinder wall I would have noticed the engine running rough or milky oil after the ride. However everything ran well and oil was clean. Can anybody confirm I am ready for the summer?

 

[ntheyer]

Re: Freeze Plug Options

Looks and sounds good. I had my engine block crack internally without pushing out the plugs. Ended up gettting a whole new engine.!<br /><br />I would recommend replacing with a brass plug if you plan on keeping the boat for a long time.<br /><br />Congratulations on not having a $2500 bill!

 

[Don S]

Re: Freeze Plug Options

I maybe didn't make myself very clear about that expandable plug. It was for testing only, not for running all the time. If you get in salt or brackish water, those plugs are only steel and will rust away in a matter of days or weeks and fall out. Normally at the worst time, when you are not watching the gauge.

 

[kwoolard]

Re: Freeze Plug Options

Don<br /><br />I am aware that the plug is not going to last a very long time in the fresh/brackish water I boat in. But days or weeks I doubt will be the case, considering everything else inside the engines water passages are steel. Besides, it only has to last me the summer since I am truly considering a repower next year. <br /><br />However, I will definetly keep a close eye on it as I do everything else on this old tired rusted out engine.<br /><br />Thanks

 

[flashback]

Re: Freeze Plug Options

kwoolard, If you removed the engine mount, you may need to re-align the drive shaft..

 

[Don S]

Re: Freeze Plug Options

Everything inside the engine where the raw water hits is Cast Iron, not just steel. Very big difference in corrosion.<br />The steal on the plug will go away very quickly. Why do you think they use brass plugs (instead of steel) same with the backing plate on the circulation pump. Brass or SS. NOT steel.

 

[kwoolard]

Re: Freeze Plug Options

Drive shaft was re-aligned, surprisingly I didn't have to make any adjustments to the engine mount. Just had to give the gimbal bearing a couple of bumps and the alignment tool slid in easily with equal grease marks.<br /><br />Don, you're probably right, but I'll take my chances this summer. Just keep your fingers crossed for me !! Hopefully it'll last long enough. I would of had to pull the engine to replace the plug with a brass replacement due to limited engine compartment space.......<br /><br />.....and if I was forced to do that, the same engine would not have gone back in.

 

[f_inscreenname]

Re: Freeze Plug Options

I know where you are coming from dude but do as Don S says. At least make up a rubber plug with brass hardware.<br /> PS You don't always have to "bang" in a cast plug you can also "push" it in. You just have to come up with the way to do it. It doesn't take much force to drive one in.