496 Vibrations
01-30-2017 | 05:10 PM
#12
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Scat Series 9000 Cast Pro Comp Stroker Lightweight Crankshafts 9-454-4250-6135
Thanks men, I don't plan on running it any longer....this is the P/N of the crank. I am trying to get a hold of a solid mercruiser contact to help determine the specs on the flywheel and outdrive coupler.
Thanks men, I don't plan on running it any longer....this is the P/N of the crank. I am trying to get a hold of a solid mercruiser contact to help determine the specs on the flywheel and outdrive coupler.
01-30-2017 | 05:16 PM
#13
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From: On A Dirt Floor
GEN V and GEN VI have externally balanced flywheels from GM and Merc. FYI Merc uses GM Flywheels, in fact, the whole damn motor is from GM, minus some of the accessories and hoses. 
Edit in: and as stated from others, even if a kit comes 'balanced' and 'drop in' , one still has to have a machine shop check/balance and you or the machine shop needs to check all dimensions and clearances.
Edit in: and as stated from others, even if a kit comes 'balanced' and 'drop in' , one still has to have a machine shop check/balance and you or the machine shop needs to check all dimensions and clearances.
Last edited by SB; 01-30-2017 at 05:18 PM.
01-30-2017 | 05:39 PM
#15
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From: On A Dirt Floor
Yes. Check with your machine shop...some will want everything including hat you said and wristpins/locks if used , rings, and etc.
Here is a good quote from this forum on flywheels that GM and Merc used. The Pat #'s are GM.
Here is a good quote from this forum on flywheels that GM and Merc used. The Pat #'s are GM.
here's more information
Part # Dia" Clutch Dia" Teeth Application
14085720 12 3/4 10.4" 153 65-69 Mark IV, Lightwweight (15 lbs), nodular iron, two-piece seal, internally balanced.
3963537 12 3/4 10.4" 153 70-90 Mark IV external balance 454, 15 lbs
3991469 14" 11" 168 66-69 Mark IV internal balance 454
3993827 14" 11" 168 70-90 Mark IV external balance 454
14096987 14" 11" 168 91-up Gen. V/IV external balance with 4" stroke forged steel crank, 454, 502
10101169 14" 11" 168 91-up Gen. V/IV external balance with 4" stroke cast nodular iron crank, 454, 502
Part # Dia" Clutch Dia" Teeth Application
14085720 12 3/4 10.4" 153 65-69 Mark IV, Lightwweight (15 lbs), nodular iron, two-piece seal, internally balanced.
3963537 12 3/4 10.4" 153 70-90 Mark IV external balance 454, 15 lbs
3991469 14" 11" 168 66-69 Mark IV internal balance 454
3993827 14" 11" 168 70-90 Mark IV external balance 454
14096987 14" 11" 168 91-up Gen. V/IV external balance with 4" stroke forged steel crank, 454, 502
10101169 14" 11" 168 91-up Gen. V/IV external balance with 4" stroke cast nodular iron crank, 454, 502
01-30-2017 | 06:23 PM
#20
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From: yorkville,il
Right on. Many of the cast rotating stroker assm are externally balanced from I remember. Why I have no clue but remember seeing some that are externally ballanced but only the cast ones.
Like everyone said don't run it til you get this taken care of or you'll be pulling engine and not happy.
Like everyone said don't run it til you get this taken care of or you'll be pulling engine and not happy.
