Mercruiser 5.7 ?

Beretta1

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Anyone know the horse power of a ‘97 5.7 V8 Thunderbolt ? OK142149 is the serial #. Also where do I find the gear ratio ? Just purchased a 1997 Bayliner Capri 2052 LS with this engine.
 
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dubs283

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Depends on crankshaft or prop horsepower. Horsepower is a great number, something most folks can relate to, however the number a boat operator should be interested is torque. That's what gets a boat up, out of the water and on step. Horsepower keeps the boat (planing hull) up and maneuverable.

Most, if not all surf/wake boat engines these days are rated by torque. Getting an additional 1500-4000 lb of water in a displacement hull moving is a tall order
 

achris

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0K142149 is the
transom assy serial number not the engine serial number.

The drive ratio should be stamped on the side of the upper housing. You'll also find the drive serial number there. Post that here and we can tell you what the ratio is. It should be 1.5:1 or 1.47:1.


Chris.....
 
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Beretta1

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transom assy serial number not the engine serial number.

The drive ratio should be stamped on the side of the upper housing. You'll also find the drive serial number there. Post that here and we can tell you what the ratio is. It should be 1.5:1 or 1.47:1.


Chris.....
That serial #is right under the Mercruiser logo where the transom assembly is bolted to the transom. It’s not the engine. Thanks
 

achris

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That serial #is right under the Mercruiser logo where the transom assembly is bolted to the transom. It’s not the engine. Thanks
To detrmine what engine you have, we need the engine serial number.
 

Bondo

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Anyone know the horse power of a ‘97 5.7 V8 Thunderbolt ? OK142149 is the serial #. Also where do I find the gear ratio ? Just purchased a 1997 Bayliner Capri 2052 LS with this engine.
Ayuh,.... Welcome Aboard,..... 2bbl. carb,..?? 4bbl. carb,..?? Efi,..?? Mpi,..??
 

Scott Danforth

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1997 should be a vortec motor (8 intake bolts)

Motor will be prop rated.

As Bondo asked, what induction system?
 

Rick Stephens

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Sorry, Don’t know.

New to you boat means time to go through and do all maintenance items that the previous 'bored with his boat' owner neglected for the last 10 years. In that process you will be pulling the flash arrestor off and seeing what carburetor you have. Don't skip on doing bow to stern inspection and maintenance or it will end up costing you mucho big $$ to to fix that little odd or end that fails.
 

Scott Danforth

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Agree. Time to pull the drive and do a complete drive maintenance, check u-joints, bellows and alignment. Do a compression test. All cylinders should be between 140 and 150 psi

Do your engine oil service, ignition service and other boat side service.

Do a trailer brake service, bearing service and general inspection.

Your serial number comes back as 2 barrel or 4 barrel carb

If 2 barrel, 230hp (closer to 240) if 4 barrel 260hp (closer to 275hp)
 

achris

More fish than mountain goat
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Engine SN- 0K147527
Transom SN- 0K142149
Drive SN- 0K047735
Engine:
Model: 457B100KT
1997 Non-Vortec, '5.7L' 2 bbl carb, Thunderbolt V, serpentine belt.
235hp (Propshaft)

Drive:
Model: 5010147KS
1997 Alpha One Gen II, 1.47:1 ratio

Chris......
 

dubs283

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Gonna guess 4600-4800

I shoot for 4500 most models but some push it up a bit for spec.

It should note to the operator on the engine tag, most likely sticker on the rain hat for max wot range
 
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