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roaddoc

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hi i have a 1986 4winns 195 ho

hi i have a 1986 4winns 195 horizon cuddy. it had the 4cyl 170hp merc in it that threw a rod. i have replaced it with 350 chevy. i originally was told that the original outdrive was ok to use with the 350. it seemed to work but there have been 2 times now where the engine has seemed like it could not get the boat up out of the hole and both times caused an engine failure where i had to pull the engine and rebuild it again. so my question is do i need to change the outdrive to a different ratio or is there was something wrong with the one i have. i know some about engines but nothing about outdrives. any advice would be greatly appreciated.
 
The drive ratio should have be

The drive ratio should have been 1.84 and that would make the motor rev higher than the 1.50 used for a V-8 application.Failing to get out of the hole really shouldnt kill a v-8 unless it was running lean or the timing was off to begin with.
 
"still wouldnt blow up a motor

"still wouldnt blow up a motor, coupler maybe .whats the pitch and dia. of the prop you have now?"
 
"[b]"and both times caused

""and both times caused an engine failure where i had to pull the engine and rebuild it again."

Ayuh,...

What Exactly is "Engine Failure",..??
What are the replacement motors Doing,..??"
 
the first time it cracked a pi

the first time it cracked a piston and cyclinder wall. so i replaced all pistons with high preformance keith black pistons. the second time i'm guessing is a rod....i haven't pulled the engine yet but it knocked a hole in the block and pan.
 
"outdrives don't make rods

"outdrives don't make rods go through blocks. improper assembly makes rods go through blocks.
Unfortunately the art of failure analysis seems to be dead. The cause can not be known until disassembled and properly analyzed.
Most common way a rod windows the block is a piston seizes due to overheating, and then the rod pulls out of the seized piston.
You reused a block with a cracked cylinder wall?
I would recommend a new crate 350 long block, or a good used 350 truck motor (preferably still in the truck so you can drive it) that you can gear run, test compression and oil pressure.
I'm rebuilding a 350 right now. And it needs basically nothing... just a hone and bearings and rings and valve guides, cam and lifters... and with my free labour, it's still going to cost me the same as a new crate 350.
Good thing I enjoy the work."
 
i sleeved the block after the

i sleeved the block after the crack. the boat ran great for a year and a half after the first repair of the new engine. i hadn't noticed it overheating and both well actually all three failures were within minutes of launching the boat. i appreciate all the input.
 
"Ayuh,...

Without seeing th

"Ayuh,...

Without seeing the pieces,...
It sounds like a lack of water flow might be the root cause...."
 
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