#1  
Old 05-28-2024, 05:21 PM
ponchjoe's Avatar
ponchjoe ponchjoe is offline
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Default Can anyone tell me what this is for?

Hi guys,

My brotherís 74 GT has a crank, no start issue and I will be starting to diagnose it for him tonight. Iím going to look at neutral safety and module type issues but what is this fuse holder for that appears to go to the HEI?
Thanks
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  #2  
Old 05-28-2024, 06:43 PM
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Default

unless I am mistaken the fuse links were in the charging system - but I am more familiar with those pesky parts on a 1973 engine.

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  #3  
Old 05-28-2024, 09:26 PM
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That looks like the tach wire.

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Old 05-30-2024, 11:21 AM
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The brown wire is the signal for the tachometer off of the coil negative. It has an inline fuse to protect the tachometer, I seem to remember it's a pretty low value like 2 amp.

Common failures that cause a no start on an HEI:
A loose or corroded connection.
Coil pickup wires broken. (fairly common)
Bad HEI module. Common with no-name after market modules. Try to use the original GM "990" module.

Link to the HEI manual: http://www.pontiacpower.org/HEI.pdf

BTW, later production 1974's got HEI from the factory.

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