my goof hopefully this will help others not make the same mistake

cooterdude

Seaman Apprentice
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May 27, 2010
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33
bought a 1989 four winns sundowner off of Craigslist with a bad motor
found a used motor on Craigslist and swapped all my marine internals into the old block
got the engine installed and went to put the out drive on omc cobra btw
found out you have to remove clutch pilot bearing from crankshaft for an out drive to work
now i have to pull bell housing back off as well as the engine coupler so i can remove the pilot bearing from the crankshaft of the "new" motor
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
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you cant take the internals of one block and put in another if you want the motor to live

the only thing marine on the motor is the head gaskets, brass core plugs, cam grind and the stuff on the outside of the motor.

please explain exactly what you did.

you can re-use the crank if its within spec and has been polished
you can re-use the rods if they are within spec

you replace pistons, rings, bearings, timing chain, etc because you must bore and hone the block to get it back to true.
 

cooterdude

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May 27, 2010
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33
that does seem a little confusing i took the marine cam out of my old cracked block and put it in the low mileage truck block i found on Craigslist i put a full marine gasket kit and put the marine water pump on it from my old engine the only thing i didn't replace was the bottom end of the truck engine it was in good shape
i also swapped the heads from the omc engine and the carburetor intake from the omc engine it has the blocked coolant ports in the rear only thing i didn't think of was the pilot bushing in the crank being there gonna pull the bell housing tomorrow and try to get the pilot bushing out gonna use the old grease and drift method
been wenching since i was 10 years old built my first engine at 15 and been fixing everything but broken hearts ever since lol im 40 now so plenty of ojt
 

HT32BSX115

Supreme Mariner
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Dec 8, 2005
Messages
10,083
found out you have to remove clutch pilot bearing from crankshaft for an out drive to work
now i have to pull bell housing back off as well as the engine coupler so i can remove the pilot bearing from the crankshaft of the "new" motor

Probably found that the outdrive yoke wouldn't go all the way in?

you're probably not the only one to do that!!

Is this a GM 305/350? did you swap the old camshaft and lifters? That's a flat-tappet engine. You might end up wearing out the "marine" camshaft quite a bit faster using tappets that were "worn" to the original cam in the "new" engine.

It seems there would so little difference between the "truck" cam and the OMC "marine" cam it might not be worth switching them......
 

cooterdude

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May 27, 2010
Messages
33
the difference is the lobe separation angle most car and truck engines have a 110% separation angle the omc cam has a 112%
it helps to make sure water doesn't back-feed through the exhaust both cams were flat tappet i used the lifters out of the omc engine on the lobes they came off of with plenty of lube they should seat back to the cam with no problems
 

HT32BSX115

Supreme Mariner
Joined
Dec 8, 2005
Messages
10,083
the difference is the lobe separation angle most car and truck engines have a 110% separation angle the omc cam has a 112%
it helps to make sure water doesn't back-feed through the exhaust both cams were flat tappet i used the lifters out of the omc engine on the lobes they came off of with plenty of lube they should seat back to the cam with no problems

Clearly not much difference between a truck engine and a marine engine......That was smart to use the original lifters! :thumb: :thumb:
 
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