how fast should water come out of cracked block vs plug

[Phantom17]

Looked at an 18 foot bowrider the other day. Not sure if the block was cracked or a freeze plug went. I would think it would gush from a freeze plug, but how fast on a cracked block?

 

[Don S]

Re: how fast should water come out of cracked block vs plug

That would depend on how big the crack is. Anywhere from very slight to as bad as a freeze plug missing.

 

[rbezdon]

Re: how fast should water come out of cracked block vs plug

I had a huge crack, U shaped under the Y of my 350 mear the motor mounts. Most of the water jacket wall was pushed out almost 1/2 inch. May have been worse than a freeze plug. No way to tell. Either is bad as the only way to repair them is to pull out the engine and asses the damage.

 

[Phantom17]

Re: how fast should water come out of cracked block vs plug

Cheap money boat. Dealer wasn't sure if it was plug or crack. Like you said, have to pull engine to find out. It's in the back. 3.0 If it wasn't on a brand new trailer (he bought a new boat, paid for a new trailer, and took the new boat on his old trailer).........things that make you go hhhhmmmmmm

 

[rbezdon]

Re: how fast should water come out of cracked block vs plug

My guess, assuming a crack, you'll spend 2 to 3 grand fixing it so it better be a real cheap boat, and thats doing most of the work your self. Freeze plug less as you could skip the new engine block. Remote chance you could weld it, I did mine and it ran for about 12 years that way but seeing as you dont know you sort of have to plan for the worst case and hope you get lucky.

 

[Phantom17]

Re: how fast should water come out of cracked block vs plug

I have a gm 2.5 in great shape sitting in my lawn ornament right now. I beilieve thats the same block. (mine is an OMC) I'll change over the exhaust/intake and whatever else, and hopefully that 2-3 grand turns into 2-3 hundred!<br /><br />Your thoughts on this? Mine is an 81 2.5, the one in the stingray is an 85 merc 3.0

 

[Bondo]

Re: how fast should water come out of cracked block vs plug

Your motor Will fit,......<br />But,....<br />If that little 3.0l Runs Good,..........<br /><br />I'd Find that Crack,.... Clean it up Real Good,+ Epoxy it,..........<br />Done Right,..... It'll last till it's Frozen Again..............<br /><br />Go Boating,+ Have Fun,..........

 

[Phantom17]

Re: how fast should water come out of cracked block vs plug

...and the prbable cause of this at this time of year would be lack of coolant delivery I take it?<br /><br />Would it be safe to run this for a few on a hose and see where the temp goes/ and how well it runs? <br /><br />Thanks gents. Any good marine welders that you know in the Boston area? Would rather send it to someone reliable and known by those who help.

 

[rbezdon]

Re: how fast should water come out of cracked block vs plug

I agree, the most likely cause at this time of year for a block crack of freeze plug to pop is a severe over heat. You should be able to tell this from some of the rubber stuff, especially the exhaust rubber. Another possibility is it froze and hasnt been used. One other more palatable is that it was frozen which loosened the freeze plug and running and heating/cooling poped the rest of the way out. This would be a real break. <br /><br />I also have heard/read about using something like JB weld on the crack successfully as Bondo points out. This can work I guess but it really requires a clean surface so spend the time to do it right the first ime of you try it.<br /><br />Good luck and I sure hope the boat is cheap enough!! for all the potential work/headaches!!