This is long/detailed. First thing I will say is I have literally googled hours upon hours regarding this. I rarely post but figured I would see what help/suggestions I can find out. Next thing I will say is I clearly made some very stupid mistakes with this boat, I realize now how dumb some of these decisions were, but at this point just looking to see how I should move forward.
Two years ago I bought a 1999 tahoe with 4.3 merc. A year ago the boat seemed to be overheating a bit. It still ran fine so I ignored it (dumb). Then a month or so later it hydrolocked on me because I killed the engine while going about 20mph (dumb). I had my friend who is good with boats help me out. There didn't appear to be any damage done during the hydrolock but while looking at it he realized the left manifold was getting EXTREMELY hot and a little steam was coming up. We ended up removing the thermostat altogether and replacing manifold gaskets and problem seemed solved. I was supposed to get a new thermostat but never did (dumb). Boat ran great rest of summer (about 20 days).
Winter storm snuck up on me. My friend wasn't available to winterize and shops were too busy due to so many people needing boats winterized before early storm. So I winterized it myself. I pulled the 5 plugs (3 on block, 2 on manifolds) poured antifreeze down most of the hoses, ran fuel stabilizer, changed most of the oil (it was cold so hard to pump all out), changed water separating filter, oil filer, removed spark plugs and sprayed fogging oil in them. I then stored the boat in friends small brick external garage with space heater set at 39 degrees all winter. The main thing I failed to do was run the 5 gallon of antifreeze through the exhaust like everyone says to do (dumb). I left 5 plugs and several of the hoses disconnected all winter (dumb?). Last thing to note is that one of my "new" left manifold gasket fell out while winterizing. I live is Oklahoma and we did have a pretty rough winter.
Moving now to last week, I hooked everything up and it started fine. Ran it for a couple minutes on muffs, was happy. Wanted to start it one more time after washing it before taking it to where I store it: hydrolocked. I won't go into details but I naively thought it was related to car wash. I pulled the plugs, hand cranked flywheel (didn't really see any water come out), put plugs back in and it started great. Ran it for a few minutes on muffs . Turned it on and off a couple times, reved it, ran perfect. Next day went to start it before taking it to storage and hydrolocked. I again pulled plugs (one on left side was fouled), sprayed marvel mystery oil in holes, hand cracked and again didn't see any water come out. Thats how I have left it. There appears to be water in the oil as the dipstick is really high. I did pump out about 2 cups worth but couldn't tell any discoloration or milkiness.
I just went and inspected it using a mirror, i don't really know where all to look but I didn't see any cracks in block (from where I can see). I did however see a pretty good crack in the water recirculating pump. This obviously needs to be replaced.
Earlier this week we very randomly got down to 32 degrees so I went ahead and pulled the 5 plugs just to be safe. Zero water came out of the left manifold. None. These are the original manifolds (15 years old) and after googling realize they need to be replaced.
I realize given the timing, all signs point to cracked block. But given my overheating last summer, cracked water circulating pump, and apparent issues with the left manifold (including missing gasket), I am wondering if this might be something besides cracked block.
My next step is waiting on boat friend to come do compression test with his gauge he plugs is spark plug holes.
Two years ago I bought a 1999 tahoe with 4.3 merc. A year ago the boat seemed to be overheating a bit. It still ran fine so I ignored it (dumb). Then a month or so later it hydrolocked on me because I killed the engine while going about 20mph (dumb). I had my friend who is good with boats help me out. There didn't appear to be any damage done during the hydrolock but while looking at it he realized the left manifold was getting EXTREMELY hot and a little steam was coming up. We ended up removing the thermostat altogether and replacing manifold gaskets and problem seemed solved. I was supposed to get a new thermostat but never did (dumb). Boat ran great rest of summer (about 20 days).
Winter storm snuck up on me. My friend wasn't available to winterize and shops were too busy due to so many people needing boats winterized before early storm. So I winterized it myself. I pulled the 5 plugs (3 on block, 2 on manifolds) poured antifreeze down most of the hoses, ran fuel stabilizer, changed most of the oil (it was cold so hard to pump all out), changed water separating filter, oil filer, removed spark plugs and sprayed fogging oil in them. I then stored the boat in friends small brick external garage with space heater set at 39 degrees all winter. The main thing I failed to do was run the 5 gallon of antifreeze through the exhaust like everyone says to do (dumb). I left 5 plugs and several of the hoses disconnected all winter (dumb?). Last thing to note is that one of my "new" left manifold gasket fell out while winterizing. I live is Oklahoma and we did have a pretty rough winter.
Moving now to last week, I hooked everything up and it started fine. Ran it for a couple minutes on muffs, was happy. Wanted to start it one more time after washing it before taking it to where I store it: hydrolocked. I won't go into details but I naively thought it was related to car wash. I pulled the plugs, hand cranked flywheel (didn't really see any water come out), put plugs back in and it started great. Ran it for a few minutes on muffs . Turned it on and off a couple times, reved it, ran perfect. Next day went to start it before taking it to storage and hydrolocked. I again pulled plugs (one on left side was fouled), sprayed marvel mystery oil in holes, hand cracked and again didn't see any water come out. Thats how I have left it. There appears to be water in the oil as the dipstick is really high. I did pump out about 2 cups worth but couldn't tell any discoloration or milkiness.
I just went and inspected it using a mirror, i don't really know where all to look but I didn't see any cracks in block (from where I can see). I did however see a pretty good crack in the water recirculating pump. This obviously needs to be replaced.
Earlier this week we very randomly got down to 32 degrees so I went ahead and pulled the 5 plugs just to be safe. Zero water came out of the left manifold. None. These are the original manifolds (15 years old) and after googling realize they need to be replaced.
I realize given the timing, all signs point to cracked block. But given my overheating last summer, cracked water circulating pump, and apparent issues with the left manifold (including missing gasket), I am wondering if this might be something besides cracked block.
My next step is waiting on boat friend to come do compression test with his gauge he plugs is spark plug holes.