Using an automotive camshaft in a marine aplication

labrooker

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Jul 24, 2010
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Ok so im rebuilding this motor. got a block from a junk yard, but the block i got has a balance shaft and the bad block out of the boat doesnt. i have been told that i have to use the crank shaft out of the boat motor, which i did. but the camshaft is too short to catch that extra gear behind the timing chain in the front of the motor because of of that extra gear for the balance shaft. is it ok to use the crank out of the boat motor and the camshaft out of the automotive motor. also had to use the front cover off of the automotive motor because size was different because of the balance shaft. the arm that is on that front cover to set the timing is set up for a smaller diamater harmonic balancer than was on the boat can i use the automotive harmonic balancer without messing up how the timing
 

Alpheus

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Re: Using an automotive camshaft in a marine aplication

You cant swap internals from a balance shaft engine to a non balance shaft engine and vise versa. These are 2 different engines...
 

labrooker

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Re: Using an automotive camshaft in a marine aplication

nothing at all? not pistons crankshaft or anything. because i have crank, pistons connecting rods connected to crank motor turns over just fine all gears are same diamater with same number of teeth everythinkg seems to move good. and all bolt paterns on oil pan and heads are the same.rods and lifters are identical, intake manifold fits right , also all clearnces on connecting rods to crankshaft are up to specs in the book. so far the only difference i have found is the front cover is taller on top to cover the balance shaft. i do understand that they are different motors but what about it wont allow it to work?
 

dukebrown

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Re: Using an automotive camshaft in a marine aplication

The motor with the balance shaft is balanced for a specific weight crank shaft, pistons, etc. and will not be happy.
 

windsors03cobra

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Re: Using an automotive camshaft in a marine aplication

Yeap you've got too new of a motor, that truck cam equipped 4.3 would probably be fine.
I would put the junkyard motor back together and taker it back altho it sounds as if you may be past "the point of no return".

Good luck
 

Bondo

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Re: Using an automotive camshaft in a marine aplication

Ayuh,... I agree with the above,...
Use ALL of the replacement motor, instead of Just the block...
 

labrooker

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Re: Using an automotive camshaft in a marine aplication

what if i remove the balance shaft honostly im trying not to sink any more money into this boat its a 92 maxum really just want to get the rest of this year out of it and start shoping for a new one this winter, but at least if this thing is running somewhat i can still sell it and get something for it. and the truck i pulled the motor out of was a 92 blazer. and yes i am past the point of returning the motor to the junk yard just dumped the bs parts in the dumpster this morn lol
 

labrooker

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Re: Using an automotive camshaft in a marine aplication

so bondo it is ok to use automotive crank , cam, ect...... what about the heads
 

Bondo

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Re: Using an automotive camshaft in a marine aplication

so bondo it is ok to use automotive crank , cam, ect...... what about the heads

Ayuh,.... Do ya wanta go Boatin',..?? or keep playin' a Mechanic,..??

Throw the Blazer motor back together as itself, then dress it in the Marine accessories....
Block, Crank, Heads, even the Cam will be Just Fine....
Use quality gaskets, 'n brass coreplugs...

Then go Boatin'......;)
 

chaparall villain 2

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Jul 15, 2010
Messages
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Re: Using an automotive camshaft in a marine aplication

i agree i would use all the parts from the blazer motor together and if you wanted to put a cam that has somewhat marine specs in it use one for the blazer engine that has simalar specs i definetly wouldnt try to mix the two assemblies ... might end up a mess
 

rodbolt

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Sep 1, 2003
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20,066
Re: Using an automotive camshaft in a marine aplication

simply slap it together,using at least 4 tubes of silicone, and jam the throttle right wide open and enjoy the wind in your hair and the sun in your eyes.
its nothing but a car motor,right?
 

bigdan1

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Aug 9, 2010
Messages
95
Re: Using an automotive camshaft in a marine aplication

beside this internal balance shaft ,there is ni difference between those two engines .....

and yes you could use a car or truck engine camshaft in a marine engine
the torque curve might be different

i`m planning on putting a comp cam 260H in my 3.0L ....with ported head should give around 35hp more , and higher rpm limit !
 

labrooker

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Jul 24, 2010
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Re: Using an automotive camshaft in a marine aplication

thanks guys for all ur imput im so close to having this thing all the way back togeather that im just gonna finish and try to get it running in the garage before i throw itn in the boat. i should only have about another hr of work on it and she should be ready to run illl let u know how it goes
 

Azlo

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Re: Using an automotive camshaft in a marine aplication

Bigdan your putting a hot cam in a 3.0l Mercruiser? I like the sound of that!
 

Alpheus

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Re: Using an automotive camshaft in a marine aplication

beside this internal balance shaft ,there is ni difference between those two engines .....


That is 100% not true!!!

You try and put a timing chain,harmonic balancer,cam shaft from a non balanced on a balanced and see what happens...

Just because you keep asking the same question over and over again but wording a little different each time is not going to change the inevitable...
 

Azlo

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Re: Using an automotive camshaft in a marine aplication

what automotive camshaft can you use in the 3.0 then??
 
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