2001 Volvo Penta 5.0 GL cracked block

[Laneman25]

Wish I wasn't posting this but it happened. I would say that I carefully drain it each winter but obviously I didn't do something right. I have fond memories with the family on this boat. I always drain the two plastic plugs under the risers, both block drains, and the water pump. I also run a zip tie in and out of the drains to make sure all water comes out. The crack is T shaped just below the dipstick tube where yo see the water stains. Any chance of a JB weld or something, or is it toast?

 

[Chris1956]

Gee, sorry that happened. Water is tricky and can get trapped in areas of the block. I always filled my block with straight automotive antifreeze for winter, since I was always uneasy about water hiding somewhere.

The good news is that rebuilt blocks are plentiful and relatively cheap. On MerCruisers, blocks are pretty easy to replace, once you get the hoist figured out. Hopefully V-P is the same.

 

[Laneman25]

Well I've watched a few videos and several boat owners had long term success with JB weld. If anyone here has tried it please add some tips.

 

[Lou C]

You also have to pull off the bottom of the big hose between the 'stat housing and the front circulating pump, did you do that?
GM cast iron blocks were never meant to be open cooled due to how cast iron rusts. So many rust flakes it is easy for passages to get clogged with rust flakes or even just sediment etc. from shallow water. I have a set of picks that I use to rod out the block drains each time I winterize it. When/if I repower my boat it is getting a half closed system for the block. Much better, easier to winterize and longer engine life.
One thing I noticed is this, it really helps to fill the block with the correct PG antifreeze for winter, because I have found that I rarely if ever have to poke one of the drains to get it to drain fully. It reduces corrosion when the boat is in storage, that's my opinion. And unlike many here, my use is 100% salt water. Block is original, heads were replaced 9 years ago (past overheat damage).

 

[Laneman25]

You also have to pull off the bottom of the big hose between the 'stat housing and the front circulating pump, did you do that?
GM cast iron blocks were never meant to be open cooled due to how cast iron rusts. So many rust flakes it is easy for passages to get clogged with rust flakes or even just sediment etc. from shallow water. I have a set of picks that I use to rod out the block drains each time I winterize it. When/if I repower my boat it is getting a half closed system for the block. Much better, easier to winterize and longer engine life.
One thing I noticed is this, it really helps to fill the block with the correct PG antifreeze for winter, because I have found that I rarely if ever have to poke one of the drains to get it to drain fully. It reduces corrosion when the boat is in storage, that's my opinion. And unlike many here, my use is 100% salt water. Block is original, heads were replaced 9 years ago (past overheat damage).

Yes, pulled the big hoses from water pump

 

[Lou C]

So then I’d guess there was some sediment in the bottom of the block passages that prevented all the water from draining.

 

[Kosmofreeze]

I hope you can get some more life from your engine with JB Weld. However, when it comes time to sell, I don't really think that there is any difference between a cracked block and a JB welded block ... good luck.

I always cross my fingers every spring ... did I get ALL of the water out of the block? I always take a 5 gallon bucket of PINK antifreeze connected to the muffs on the final run until I see PINK out the exhaust. Then I drain the risers, block plugs and hoses. With the block plugs out and the impeller output hose disconnected at the top, I fill the hose with PINK until the PINK is running out of the block plugs. In my mind, I just filled the the block from the bottom up with PINK. Probably a belt and suspenders approach but I've made it through many northern Minnesota winters without incident. I just use the -50F stuff - when it gets cold, it'll turn to slush but very little expansion.

 

[Lou C]

If you get to zero F use -100! -50 gets hard at that temp I tested it in the freezer. Spend the extra $$$