will a pre 84 or older 5.7 mercruiser block work with 87 engine swap.

potatoe

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there is a possible complete 87 5.7 mercruiser engine that might be here soon. my question is. can everything on this 87 5.7 engine block, switch over to an early 80's or older 5.7 2 piece rear main seal block without a lot of converting. whats the difference besides the 2 piece rear main seal in the older blocks? thanks
 

potatoe

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how can i find out the year of an engine block? 5.7 mercruiser?

how can i find out the year of an engine block? 5.7 mercruiser?

is there an easy way to check the year of a block ? are the older 70's and early 80's compatible with the late 80's and newer blocks? thanks
 

picklenjim

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Re: how can i find out the year of an engine block? 5.7 mercruiser?

Re: how can i find out the year of an engine block? 5.7 mercruiser?

Easiest way to I.D. your small block Chevy is to use the casting number found on the drivers side rear of the block on the top flange that mates with the tranny bell housing.Numbers are raised approx 1/8 of an inch.The are about 3/4 of an inch tall.Even though you may have to scrap greese and dirt away,the numbers may be seen plainly. Then check here.
http://web.archive.org/web/20080516024247/http://www.mortec.com/castnum.htm
Older blocks used a 2 piece rear main seal. In '86 they went to a one piece rear main seal so the '86 and newer cranks are also different. You can get an adapter so you can run the old 2 piece seal and crank in the '86-'92 block.
http://www.jegs.com/i/Moroso/710/38415/10002/-1
Then after '92 I believe they changed again to the vortecs.
 

Bondo

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Re: how can i find out the year of an engine block? 5.7 mercruiser?

Re: how can i find out the year of an engine block? 5.7 mercruiser?

is there an easy way to check the year of a block ? are the older 70's and early 80's compatible with the late 80's and newer blocks? thanks

Ayuh,.... SBCs are 'bout the most compatible motors ever built...
They'll All interchange, with adaptions involved...
It's best to stick within vintage groups to insure an easy swap though...
The largest groups are from the begining to '79,...
'79 to '86...
'n '86 to present...
There are also sub-variations within those groups...
 

potatoe

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Re: will a pre 84 or older 5.7 mercruiser block work with 87 engine swap.

thanks for the info. does anyone know excactly what needs to be adapted to take the heads, intake, manifolds, and everything else from a 1986 5.7 engine, and put it onto a pre 79 and older 5.7 block? will the starter and alternator, and flywheel from 86 engine bolt onto the 79 and older block?or do some things need to be changed? thanks
 

Bondo

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Re: will a pre 84 or older 5.7 mercruiser block work with 87 engine swap.

thanks for the info. does anyone know excactly what needs to be adapted to take the heads, intake, manifolds, and everything else from a 1986 5.7 engine, and put it onto a pre 79 and older 5.7 block? will the starter and alternator, and flywheel from 86 engine bolt onto the 79 and older block?or do some things need to be changed? thanks

Ayuh,... It'll all bolt on, but ya wouldn't have a dipstick, 'n the flywheel might be wrong anyways...

Not enough Info....
 

dan t.

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1,137
Re: will a pre 84 or older 5.7 mercruiser block work with 87 engine swap.

The pre 87 2 piece rear main engines use a different flywheel.The dipstick swapped sides around 81 . The old style coupler that uses the flywheel bolts wont work on a 87 or newer crank, but a 87 or newer coupler will work on an older set up with the same diameter flywheel. Everything else bolts on.
 
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