1990 454 mag lost power
#11
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Joined: Apr 2006
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From: Toledo Oh
Guessing my next move to replace the distributor and rotor?
Look like the one I should buy?:
A.A Tune-Up Kit Distributor Cap Rotor for MerCruiser GM V8 Thunderbolt IV, V, HEI Ignition System 18-5273, 805759Q3 https://a.co/d/iQcMcER
Look like the one I should buy?:
A.A Tune-Up Kit Distributor Cap Rotor for MerCruiser GM V8 Thunderbolt IV, V, HEI Ignition System 18-5273, 805759Q3 https://a.co/d/iQcMcER
Im guessing your next move is to slow down and develop some trouble shooting skills. A harbor freight test light goes a long ways and they start at like $3.99
https://www.electricaltechnology.org...lor-codes.html
#12
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From: Pa
#13
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#14
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TB IV ignition troubleshooting flow chart https://bpi.ebasicpower.com/faq/MERCSB92-11.htm
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#20
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From: On A Dirt Floor
Furthermore….your coil looks like this.
Looking at carburetor from frt of engine, it is just behind the carb to the right.Puple wire terminal is + and grey wire terminal side is -.

Last edited by SB; 10-16-2022 at 05:11 PM.




