compression test came back low

Tomfuller

New User
Hey I just did a compression test on the tractor three of the four cylinders at 50 pounds the second one back from the radiator came back at 40 pounds per square inch. What should I be looking for now to figure out what my problem is? I should have the head off today and I will be able to look into it a little bit better. Any help will be appreciated very much!! Thank you.
 
Before you remove the head -- How did you do the test? Tractor should not run at all with those numbers.
 
I just turned it over without having the key on. I had oil in my radiator fluid and radiator fluid in my oil so I thought I'd blew my hed head gasket. It isn't running. I was just in a field and it's better than sputtered and Beck fired a couple of times and just died.
 
Did you have the throttle at wide open full throttle when you did the test and at least 5 whoompas each cylinder.

Your low readings could be from throttle at full idle.
 
Throttle was wide open and I went until the compression tester was not going any higher was like 5 or 6 rollovers.
 
The tractors not running I do believe I have a blown head gasket and I just turned it over it was not under power and it was not idling.
 
A "blown" head gasket could affect one or two cylinders but not all four except in the most rare of circumstances.

Dean
 
It would be a very, very rare occurrence for a blown head gasket to affect ALL four cylinders! One & two, but not all four.
 
If you haven't already pulled the head you may want to run the compression test again with the air intake removed from the carburetor and verifying that the butterfly valve is fully open at full throttle. You may have an air restriction in the system (Plugged filter). That can cause the symptoms you described.
 
Well I have a friend who know a bit about engines the new problem is I can't get the head off. He thinks it might be valves. Any suggestions in getting the head off?
 

"Any suggestions in getting the head off?"

i used equal parts patience, pig-headed stubbornness, and swearing to get mine off. all 3 were needed.
 
I am assuming you performed the test properly and had proper cranking speed. Normally, consistent readings which are too low point to something common to all cylinders. I would invest in a Ford manual for specs. I am also assuming you have everything removed and it is stuck to the block deck which happens. A deadblow may help loosen the head but be gentle. Be careful about prying anywhere on a sealing surface.
 

Mine was a little stubborn. I took a piece of cherry wood (pine would probably work...but I had a cherry cutoff from a recent project handy) that was maybe 1-1/2" square and about a foot long....I placed that against the side of the head at various places and gave it a few taps at the other end with a hammer.

I then took a very sharp, 3/4" wood chisel and placed it bevel up right where the gasket seam is and gave it some gentle taps. Just enough to see the head budge a little. I didn't hit it hard enough to actually drive the chisel between the head and the mating surface any more than maybe 1/8" or so. All I wanted to do was get the tip of the bevel in there for a tiny bit of wedge action.

I got it wiggling a little and then finished prying it off with some plastic auto-body trim removal tools. A couple of wooden spatulas from Walmart with their ends "sharpened" would also make safe prying devices.
 
Thanks to everybody for all the help! I'm letting penetrating oil
seeping around the bolts and then I will get at it again.
 

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