8N tractor 1947 compression problem

[papadude]

Have replaced spark plugs - rebuilt carb and did distributor and finally as last resort bought "compression gauge" and compression was all cylinders was 30 :? book says 90 compression - now WHAT? any good advise from ol timers out there? Andy

 

[John (TR)]

Next step is to add a tablespoon of oil to each cylinder and re-check. If the compression increases you have worn rings, if it stays the same bad valves. Did you have all the plugs out and a fully charged battery when testing? Assuming your readings are correct that motor should not run let alone start.

 

[Jerry/MT]

With those compression numbers( 30 psig) your valves are sticking!

 

[Ultradog MN]

I had to go back and see your prior posts. So you have not heard this tractor run, correct?
How long has it sat?
Are you sure you are doing a compression test correctly? What type of tester are you using? Screw in?
If you are confident your CT is correct then the next thing I would do is pour MMO or ATF down the spark plug holes. Turn the engine over by hand and let the pistons force the oil back out of the SP holes. This will push oil over the top of the block and cause it to spill over the valves and guides and maybe oil some sticky valves. Also remove the side covers and determine which valves are stuck. Spray any stuck valves from the bottom. Treat them with daily doses for a week. Keep turning it over.
So glad you didn't rip the head off of this engine like so many here do. A little patience which it looks like you have might make a runner out of it yet.

 

[Hobo,NC]

Google, cylinder leakage test

 

[Bob]

Mot to mention the fact the compression tester probably has "issues"!

 

[papadude]

Ultradog MN
PostPosted: Wed May 04, 2011 5:10 pm Post subject: Re: 8N tractor 1947 compression problem
I had to go back and see your prior posts. So you have not heard this tractor run, correct?
How long has it sat?
Are you sure you are doing a compression test correctly? What type of tester are you using? Screw in?
If you are confident your CT is correct then the next thing I would do is pour MMO or ATF down the spark plug holes. Turn the engine over by hand and let the pistons force the oil back out of the SP holes. This will push oil over the top of the block and cause it to spill over the valves and guides and maybe oil some sticky valves. Also remove the side covers and determine which valves are stuck. Spray any stuck valves from the bottom. Treat them with daily doses for a week. Keep turning it over.
So glad you didn't rip the head off of this engine like so many here do. A little patience which it looks like you have might make a runner out of it yet. can u contact me at [email protected] or 775 538-7627 thanks papadude (Andy)