98 454 mag mpi starting issue
#1
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From: KY
I’ve been chasing this gremlin around all year long and finally need some advice….
I have narrowed it down to the circuit breaker box on top of he motor has a click when you hit the key. It feels like the Mercathode box is clicking. It would work great a few times out then you’d have to hit the key a few times with the click. I have replaced batteries, the solenoid in the box that looks like the trim one, checked connections, and tested all connections with a light. I’m stumped and hope someone can help out here!
I have narrowed it down to the circuit breaker box on top of he motor has a click when you hit the key. It feels like the Mercathode box is clicking. It would work great a few times out then you’d have to hit the key a few times with the click. I have replaced batteries, the solenoid in the box that looks like the trim one, checked connections, and tested all connections with a light. I’m stumped and hope someone can help out here!
#3
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From: KY
#5
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From: KY
[QUOTE=AllDodge;4810701]Look in the box to see if you see the slave relay (can be one of 2 types). That is used to apply power to the starter solenoid
I have replaced that twice, seems to me like it’s clicking from the mercathode box. I’m unfamiliar with that system and maybe it’s another box relay in there. Didn’t know if anyone had this issue before or what I should look for/at.
I have replaced that twice, seems to me like it’s clicking from the mercathode box. I’m unfamiliar with that system and maybe it’s another box relay in there. Didn’t know if anyone had this issue before or what I should look for/at.
#6
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From: KY
Could be you need to clean connections. Corrosion on a connection will not pass full voltage. Use a voltmeter and see what the voltages are prior to starting and while trying to. If voltage drops much at all then its corrosion or need a larger battery.
#8
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From: KY
ok, thanks! That’s where I was headed next with it. Has 2 new 1000 cca batteries in it. I’d think that’s plenty for a single 454 but who knows electric isn’t my forte and that’s why I’m here asking lol
#9
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From: On A Dirt Floor
$10 the click from mercathode is actually from remote solenoid which is right next to it.
When it clicks (not starting) connect big posts of relay with screw driver or ? and see if cranks. If it does, it’s typically the starter relay or it’s ground or wire connections. If it doesn’t it’s typically the starter or it’s wire connections.
When it clicks (not starting) connect big posts of relay with screw driver or ? and see if cranks. If it does, it’s typically the starter relay or it’s ground or wire connections. If it doesn’t it’s typically the starter or it’s wire connections.





