Grounding coil for compression test

Kubaat3lover

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Hello folks
Simple question, I’ve read in service bulletin that for compression test I have to remove middle plug from coil and ground it to the block, right??
But doesn’t it just short out the coil?
Or maybe remove positive terminal from coil
 

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Rick Stephens

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Even though it is not the recommended way, I just pull the coil to cap wire. All gonna die one day anyway.
 

Kubaat3lover

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Yes I mean the wire from coil to the cap
 

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alldodge

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^^ Many times did the same thing (Ricks post)
It says to ground it so there is no spark that might cause a fire. So the coil wire can be grounded

OR

With a T Bolt just disconnect one or both of the bullet connectors coming from the distributor

OR as you say disconnect the + side
 

Kubaat3lover

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It’s TB V ignition , but just grounding the wire from coil to cap won’t shorten it out?..

so to be sure. Ground this wire ??
 

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Scott06

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It’s TB V ignition , but just grounding the wire from coil to cap won’t shorten it out?..

so to be sure. Ground this wire ??
Yes take it off distributor and put it on a grounding point on block or intake. it allows a path to ground for the spark , just like in your spark plugs when they fire...

Or as AD pointed out you can disconnect the two bullet connections to distributor sensor and no spark will be made.
 

bruceb58

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By just leaving it open, that's a sure way to blow out the coil. When it is open, that high voltage has to go somewhere so it blows through the insulation inside the coil trying to find a ground. By grounding it, you don't have that issue.
 
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