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bravo 3 big block won't crank

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diamondl

New member
went to the lake, started, idled for a minute, and backed off trailer. when i do this i keep the engine compartment open just as a precaution (water or fuel leaks, etc.) when i got my head out of the engine compartment i noticed some blue/gray smoke coming from under the swim platform. i instantly shut it down and looked harder for some sort of problem. couldn't find any thing wrong so i restarted and checked all the gauges. it was running smoothly but hotter than usual, about 210 instead of 175, and it seemed hot to the touch. when i saw that it was hot i pulled back to the dock and tied up. total run time was probably 6 or 8 minutes, and i turned it off and restarted at least 5 or 6 times. when my wife got back from parking i tried to restart but now it won't crank over. the closet actual boat mechanic is 130 miles one way. how can i tell if the engine seized up or something else is keeping it from cranking. help!!
diamondl
 
batteries have plenty of juice and even tried it while on the onboard charger, it clicks hard but doesn't turn. if it was a truck motor i would put a wrench on the damper pulley and see if turns by hand, but there's no big bolt!
 
take the spark plugs out and see if water shoots out the holes if it cranks.

Post back stop trying to crank it till you remove the plugs
 
Try pulling out all the spark plugs and see if it will turn over, also look for water when pulling out the spark plugs, Also look for water spraying out of the cylinders if & when it turns over.

I think you should do this as soon as possible, Also if i were you I would not turn it over until the plugs are out, Because if water is in the cylinders your going to a lot of damage to the internal engine components.

Then do a engine compression test while the plugs are out.

Good luck.
 
Agree with above water ingestion possibility. You'll want to check the oil level now too. Probably high, water in oil pan. You'll also want to open up the exhaust "Y"/horn behind the engine and check the condition of your exhaust shutters.
 
Dont forget that is the lower unit is seized up, or the belolow leaked and let water into your ujoint, that will give you engine locked symptoms.
 
have learned much since this post was started. pulled the plugs and found water in the cylinders, as most of you expected. did a compression test that turned out not too bad. most were 120 - 125, with one at 105. both of the cylinders beside the 105 were at least 120. i have removed the elbows and manifolds which look ok to me. seems like the gaskets between the elbows and manifolds were leaking. have changed the oil, found about 3 quarts of water in there! today's exercise will be looking for the flapper valves. i have heard that the intake manifold has water running thru it, and that if the block cracked, which i really doubt, it would be under the intake. that will probably be tomorrow. nothing left then but the heads, i was hoping that the compression test meant i wouldn't have to pull the heads. if it get this far down it would be a shame not to freshen it up a bit. have read about all the special tools it takes to pull the outdrive. anyone know if that's true? you still there chief?
thanks again!
diamondl
 
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