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Need help selecting an engine to buy

J

joespliv

New member
I have a 1986 Cruiser Inc. Holiday26 boat with a Chevy305. 1986 is a break year for Chevy engines, meaning thatis the year Chevy stopped building their engines with a two piece rear mainseal, and started building their engines with a one piece rear main seal. Unfortunately for us 1986’ers, the only way to know which one I have is to pull the engine, and look at the rear of the engine. I have a dilemma: Theengine is in the boat needs to be replaced, and I don’t have access to it to doa visual inspection. I do have thenumbers off the engine block 14088548. Theintake manifold has twelve bolts. All twelvebolts are on an angle. Can anyone tellme if I have a one piece seal engine, or a two piece seal engine?
 
[FONT=Century Gothic, Arial, Helvetica]86 350 BLOCK ID # VIN CODE "L" HEAD ID #
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[FONT=Century Gothic, Arial, Helvetica] 14088548[/FONT][FONT=Century Gothic, Arial, Helvetica] 462624, 14071114[/FONT]
[FONT=Century Gothic, Arial, Helvetica] Notes: CARB, 10/30 Series, 1 piece rear main seal, 2-bolt mains, edge bolt valve covers
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If memory serves me, the SBC 5.0L and 5.7L were each one year apart with regard to the change from the 2 pc rear main seal to the 1 pc.
I don't recall which one was first..... I'm thinking that is was the 5.0L.
At the same time, GM began casting the displacement into the blocks.
Also, the valve covers became "center" bolt down, instead of "perimeter" bolt down.... but this may have been during the following year.

Look at the rear Port side of the block just forward of the flywheel cover flange.
If these are 1 pc rear main seal engines, you'll see a 5.0 or 5.7 cast into the block.

As shown in the upper left hand corner here.
(this one is an early 2 pc rear main seal engine block)






This one is a post '86 or '87 1 pc rear main seal engine block noted by the displacement #'s.




The only difference for you, should be the crankshaft flywheel flange style.
Later crankshaft left side................................... earlier crankshaft right side.




The later flywheel is also available in 153 tooth as well as 168 tooth.
The 153 is a Camero car application w/ std transmission.


For a better SBC Marine build, see this thread beginning at post #7.

You can do much better than what GM does regarding piston selection.


.
 
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