compression test
 

I would like to do a compression test on my '30 Model A. I didn't buy the gauge yet but I also know i will need an adapter to thread in to the spark plug holes. Can anyone tell me what size and where can I find it? Jim

Re: compression test
 

The vendors have them. 7/8-18 thread.

Re: compression test
 

Vendors sell 14mm spark pug adapters. At Snyders the part number is A-12405-ADP and the price is $6.75.

Re: compression test
 

They still sell the handhelds which have a tapered rubber cone. Just hold it in the hole, crank away and watch the needle. They work just fine for our old easy to get at monsters.

Re: compression test
 

AutoZone will lend you a compression tester at no charge under their loan-a-tool program, so you only need to buy the adapter. Remember to set the throttle fully open.

Re: compression test
 

I bought a tester from Harbor Freight and the adapter from Snyders. The tester was the screw-in type. It's easier than using the rubber tipped compression gauge if you're doing it alone because you need to sit in the car to press the starter switch with your foot.

Re: compression test
 

I just push the starter rod with my hand.