The Ford Barn

Bassman/NZ · 03-24-2015, 01:46 AM

Dang! My C59A with high compression heads, but otherwise stock, was running a bit ragged coming home from work today. Ran a compression test......
165
155
145
170
135
155
60
145

Sigh ..........

Talkwrench · 03-24-2015, 04:48 AM

Wwww crap! Guess I shouldn't complain about my gearbox then...

Walt Dupont--Me. · 03-24-2015, 05:57 AM

Bring the low cyl up close to TDC and make or get an adapter to screw into the plug hole and put some air in the cyl to see where the com. is going. What are the heads your using to get a stock bore and stroke 59ab up to 170 compression? Walt

Vanspeed · 03-24-2015, 08:19 AM

My 59A had Weiand cheaters on it and it had around 170 but it was not stock.

keith oh · 03-24-2015, 10:27 AM

My 21 bolt engine started missing after setting for o couple of months this winter, had irratic compression readings. Poured MMO down both sides of Carb. with running engine and it smoothed out and runs great now. Compression is back to 120 to 125 on all cylinders. It pays to try the simple things first.

Bassman/NZ · 03-24-2015, 01:06 PM

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Quote:

Originally Posted by Walt Dupont--Me.

Bring the low cyl up close to TDC and make or get an adapter to screw into the plug hole and put some air in the cyl to see where the com. is going. What are the heads your using to get a stock bore and stroke 59ab up to 170 compression? Walt

Walt, they are stock heads milled for 45thou clearance over the pistons.

Walt Dupont--Me. · 03-24-2015, 01:27 PM

I cain't believe that stock 239 59ab with heads milled .045 has 170 compression. Try another compression guage. Walt

Scott H in Wheaton · 03-24-2015, 01:56 PM

Quote:

Originally Posted by Walt Dupont--Me.

I cain't believe that stock 239 59ab with heads milled .045 has 170 compression. Try another compression guage. Walt

That won't change the one cylinder being 50% of the others, but could be the tester is off some.

Tim Ayers · 03-24-2015, 02:01 PM

Pour some goop down that cylinder. Could be some stuck rings or a valve hanging up. I agree, try that first. Run it and then change the oil to get rid of that blow by in the pan.

Bassman/NZ · 03-24-2015, 04:12 PM

It's done about 200 miles on hone, rings, bearings, valve grind and new valve guides. I'm going to give it a run tonight and re-test. If it's still low I'll blow some air into that cylinder and see what's going on.

03-24-2015, 01:46 AM	#1
Bassman/NZ Senior Member Join Date: May 2010 Location: Napier, New Zealand Posts: 2,001	Aaarrrggghhhh!!!! Dang! My C59A with high compression heads, but otherwise stock, was running a bit ragged coming home from work today. Ran a compression test...... 165 155 145 170 135 155 60 145 Sigh ..........

03-24-2015, 04:48 AM	#2
Talkwrench Senior Member Join Date: Aug 2012 Location: Perth, Western Australia Posts: 2,706	Re: Aaarrrggghhhh!!!! Wwww crap! Guess I shouldn't complain about my gearbox then... __________________ *"Came too close to dying to stop living now!"*

03-24-2015, 05:57 AM	#3
Walt Dupont--Me. Senior Member Join Date: May 2010 Location: Gardiner Me. Posts: 4,200	Re: Aaarrrggghhhh!!!! Bring the low cyl up close to TDC and make or get an adapter to screw into the plug hole and put some air in the cyl to see where the com. is going. What are the heads your using to get a stock bore and stroke 59ab up to 170 compression? Walt

03-24-2015, 08:19 AM	#4
Vanspeed Senior Member Join Date: May 2010 Location: Suttons Bay, Mich. Posts: 3,444	Re: Aaarrrggghhhh!!!! My 59A had Weiand cheaters on it and it had around 170 but it was not stock. __________________ *Respecting and Resurrecting Ford Model A's.*

03-24-2015, 10:27 AM	#5
keith oh Senior Member Join Date: May 2010 Location: Millersport, central ohio Posts: 668	Re: Aaarrrggghhhh!!!! My 21 bolt engine started missing after setting for o couple of months this winter, had irratic compression readings. Poured MMO down both sides of Carb. with running engine and it smoothed out and runs great now. Compression is back to 120 to 125 on all cylinders. It pays to try the simple things first.

03-24-2015, 01:27 PM	#7
Walt Dupont--Me. Senior Member Join Date: May 2010 Location: Gardiner Me. Posts: 4,200	Re: Aaarrrggghhhh!!!! I cain't believe that stock 239 59ab with heads milled .045 has 170 compression. Try another compression guage. Walt

03-24-2015, 02:01 PM	#9
Tim Ayers Senior Member Join Date: May 2010 Location: NJ Posts: 6,921	Re: Aaarrrggghhhh!!!! Pour some goop down that cylinder. Could be some stuck rings or a valve hanging up. I agree, try that first. Run it and then change the oil to get rid of that blow by in the pan.

03-24-2015, 04:12 PM	#10
Bassman/NZ Senior Member Join Date: May 2010 Location: Napier, New Zealand Posts: 2,001	Re: Aaarrrggghhhh!!!! It's done about 200 miles on hone, rings, bearings, valve grind and new valve guides. I'm going to give it a run tonight and re-test. If it's still low I'll blow some air into that cylinder and see what's going on.