The Ford Barn

Reddy · 11-26-2012, 04:23 PM

What is the cylinder compression for a stock model A engine ????

Mike

Tom Wesenberg · 11-26-2012, 05:02 PM

My worn engine has only 50 lbs on each cylinder, but most people report about 60 to 65 on a totally stock engine.

Patrick L. · 11-27-2012, 06:53 AM

This is a pretty common question here.. What are your compression readings ?? I'm running a tired 51 year old engine with 45# compression.. It has enough power for me and doesn't leak anything..

socalplanedoc · 11-27-2012, 10:27 AM

Quote:

Originally Posted by Tom Wesenberg

My worn engine has only 50 lbs on each cylinder, but most people report about 60 to 65 on a totally stock engine.

Tom, what procedure do you use for checking compression?

hotrodderhaag · 11-27-2012, 10:52 AM

my compression gauge doesnt have a large enough adapter to do my model a, did you guys fab one or is your gauge that old?

Marco Tahtaras · 11-27-2012, 10:55 AM

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I suspect Tom does the same as I do. Warm engine, throttle wide open, and all plugs removed. The gauge typically hit very near peak on the third compression stroke and absolute peak on the fourth.

Marco Tahtaras · 11-27-2012, 10:58 AM

Quote:

Originally Posted by hotrodderhaag

my compression gauge doesnt have a large enough adapter to do my model a, did you guys fab one or is your gauge that old?

I believe most of the parts suppliers sell an adapter. I had a friend machine a spark plug base to make an adapter back in the early 70's as there were no ready made adapters available at that time.

Tom Wesenberg · 11-27-2012, 11:25 AM

Quote:

Originally Posted by socalplanedoc

Tom, what procedure do you use for checking compression?

Exactly as Marco said in #6.

Dave in MN · 11-27-2012, 12:17 PM

Quote:

Originally Posted by hotrodderhaag

my compression gauge doesnt have a large enough adapter to do my model a, did you guys fab one or is your gauge that old?

Use an old "take apart" sparkplug base, remove the core and then use a tap that fits your compression tool. The thread depth may be shallow, if so, a couple extra layers of teflon tape will seal it.

Or just order one from the Model A parts suppliers. Snyder's Shown

Part# A-12405-ADP

Good Day!

hotrodderhaag · 11-27-2012, 01:19 PM

just ordered the adapter from snyders,
thanks guys

11-26-2012, 04:23 PM	#1
Reddy Junior Member Join Date: May 2010 Posts: 28	Compression What is the cylinder compression for a stock model A engine ???? Mike

11-26-2012, 05:02 PM	#2
Tom Wesenberg Senior Member Join Date: May 2010 Location: Mpls, MN Posts: 27,582	Re: Compression My worn engine has only 50 lbs on each cylinder, but most people report about 60 to 65 on a totally stock engine.

11-27-2012, 06:53 AM	#3
Patrick L. Senior Member Join Date: May 2010 Location: Largo Florida Posts: 7,225	Re: Compression This is a pretty common question here.. What are your compression readings ?? I'm running a tired 51 year old engine with 45# compression.. It has enough power for me and doesn't leak anything..

11-27-2012, 10:52 AM	#5
hotrodderhaag Senior Member Join Date: Sep 2012 Location: Mooresville Nc Posts: 137	Re: Compression my compression gauge doesnt have a large enough adapter to do my model a, did you guys fab one or is your gauge that old?

11-27-2012, 01:19 PM	#10
hotrodderhaag Senior Member Join Date: Sep 2012 Location: Mooresville Nc Posts: 137	Re: Compression just ordered the adapter from snyders, thanks guys

11-27-2012, 10:55 AM	#6
Marco Tahtaras Senior Member Join Date: May 2010 Posts: 3,099	Re: Compression Sponsored Links (Register now to hide all advertisements) I suspect Tom does the same as I do. Warm engine, throttle wide open, and all plugs removed. The gauge typically hit very near peak on the third compression stroke and absolute peak on the fourth. __________________ http://www.abarnyard.com/