Merc Cruise Inboards

[pescador]

My buddies having issues with his twin Merc inboard setup on his 80’s SeaRay. Nice boat but it looks like it may need power. Any ideas in Victoria area where to pick up a couple of inboard Mercs? Not sure how inboards work but will any small block Chevy Stroker plug right in? I understand they need to be marine application but can u convert them?

 

[adrian1991]

I'll have a mercruiser 165 pulled in a bit runs excellent if your interested in nanoose. Can come see it run too if you want

 

[Wild Bill]

My buddies having issues with his twin Merc inboard setup on his 80’s SeaRay. Nice boat but it looks like it may need power. Any ideas in Victoria area where to pick up a couple of inboard Mercs? Not sure how inboards work but will any small block Chevy Stroker plug right in? I understand they need to be marine application but can u convert them?

Yup! You can pretty much start with a stock car engine, use pretty much as is or make it better. The 454 indmar inboard in my ski boat had stock truck peanut port heads, stock steel valves, Oem cast flat top Pistons, stock rods and bearings, stock single roller timing chain, stock truck cast crankshaft and camshaft. Nothing different on the longblock except they installed brass expansion/freeze plugs. The rest is bolt on. Now add a SKAT rotating assembly, aftermarket heads, stainless valves, keep compression ratio low though! 8 to 8.5/1 fine!

 

[jim morrow]

stock chev 250 cubic inch is a different casting than the genuine Mercruiser 165 hp.
stock chev doesn't have the front motor mount, on the starboard side.
some of those old Sea-Rays had twin 165's in them, and are now podded with outboard.

 

[pescador]

stock chev 250 cubic inch is a different casting than the genuine Mercruiser 165 hp.
stock chev doesn't have the front motor mount, on the starboard side.
some of those old Sea-Rays had twin 165's in them, and are now podded with outboard.

His are small block Chevy’s. They are not original. After 40 years I’m guessing these are the 3rd change.

 

[Wild Bill]

Something like this! https://www.cnc-motorsports.com/1-9...sembly-kit-96-1-keith-black-dish-pistons.html
Only checked one cdn supplier and prices looked crazy.. 3 or 4 times more not including exchange and taxes.
Eagle had some crankshaft grinding issues years ago and Scat was the go to, they probably rectified those issues.
Keep the compression ratio down so you don't have to run premium like me... Boat engine service is like driving a truck and trailer up a mountain all the time.
Hyperutectic Pistons ok as long as you don't have any detonation, forged will pass a little more oil.
Nice set of aftermarket cast iron or aluminum aftermarket heads.. seen to many engines messed up with a rebuilt factory head with a cracked valve seat. Ferrea stainless valves. Never tried aluminum heads on a salt water boat however shouldn't be an issue with fresh water cooled? 350 or 383.. 383 is a nice engine..

 

[Wild Bill]

Something like this! https://www.cnc-motorsports.com/1-9...sembly-kit-96-1-keith-black-dish-pistons.html
Only checked one cdn supplier and prices looked crazy.. 3 or 4 times more not including exchange and taxes.
Eagle had some crankshaft grinding issues years ago and Scat was the go to, they probably rectified those issues.
Keep the compression ratio down so you don't have to run premium like me... Boat engine service is like driving a truck and trailer up a mountain all the time.
Hyperutectic Pistons ok as long as you don't have any detonation, forged will pass a little more oil.
Nice set of aftermarket cast iron or aluminum aftermarket heads.. seen to many engines messed up with a rebuilt factory head with a cracked valve seat. Ferrea stainless valves. Never tried aluminum heads on a salt water boat however shouldn't be an issue with fresh water cooled? 350 or 383.. 383 is a nice engine..

And start with roller cam blocks! More power, better longevity and reliability with a roller cam.
Only downside is most blocks don't have provisions for a mechanical fuel pump and have to go electric.

 

[noluck]

And start with roller cam blocks! More power, better longevity and reliability with a roller cam.
Only downside is most blocks don't have provisions for a mechanical fuel pump and have to go electric.

you can drill the block for the pushrod and put in a mechanical pump

 

[pescador]

thanks guys. think he's found a solution. rebuilding motors.