farmall cub compression

[Robert12345]

working on 1952 farmall cub got the hood off poured in some transmission fluid in case rings bound up. my question is what compression is
normal and whats the lowest compression they will run on, big test tomoarrow. havent got manuals yet

 

[old]

I cannot give you number as such but anything around 90psi is good on a cub. But they are also known to have valves stick open. My cub when O go it had 2 or 3 valves that where stuck open

 

[Robert12345]

if i discover low compression due to vqlvedsw sticking how do i get them unstuck all input qppreciqted

 

[old]

If your lucky you can use a bent screwdriver in the plug holes to push them down and work them. If that doesn't work it is pull the head and tappet cover and go from there which is what I had to do

 

[Robert12345]

if i have the problem ill try the bent screwdriver and pull head as last resort thanks for input if i sprayed blastr in cylender qnd it rqn down vqlve stemn is there a down side in trying that?.

 

[old]

The one I had I had filled the cylinders as full as I could with ATF and let it sit a week or so and they didn't free up. I ended up having to pull the valve that where stuck and clean them up before they would work

 

[Robert12345]

ill find out tomorrow

 

[old]

The valve I had stuck I had to remove the valve spring keepers and then turn the engine over till the valves where open as wide as they would go then pry them up even more. Then carefully grab them with vise grips and pull and turn them till they came out. I then wire brushed the stems good and took a drill bit that would just fit and cleaned up the holes they fit in

 

[grandpa Love]

Post your compression numbers tomorrow. We have one cub read between 55-65 psi ... Had to pull it around the yard to get it started. Couple years later it runs great, no smoke. And starts easy, with the starter! Lol. Stuck valves are an easy fix. Take valve cover off behind carb, that way you can see what's going on. You can run tractor with cover off, no harm. We usually spray any stuck valves with Free-All or Deep Creep every day for several days. Spray it in plug holes too. Happy to help any way we can. Love our herd of Cubs!

 

[old]

Tried to call you a hour or so ago to check how your holding up in what is suppose to be bad weather down your way

 

[Robert12345]

hopefully it wont come to that, my reluctance to takeing the head off is i hear rboken head bolts are common do you have any tricks on how to get head bolts out with out breaking them.

 

[old]

I've never had head bolts break so not sure how to keep it from happening other then if you can hook it up to a hot water hose to heat the block before you try to remove them as in sort of flush the cooling system which will heat the engine up

 

[BarnyardEngineering]

There's no way to predict if a bolt is going to break, or any effective ways to prevent it. The threads are in the block, which is through the head, so spraying the heads of the bolts with, whatever, is a waste of spray. It will never get to the threads.

You just have to approach it like removing a well-stuck band-aid. Rip it off and deal with any pain that might result.

 

[Robert12345]

took compression today 3 75psi one 85 psi i dont have the facility to get to engine by splitting tractor , if i wanted to raise the compression i could remove head and give it a valve job, i hope it will run with those numbers , next step get good spark and try to get it to run. need all the help i can get . you think vqlve job will rqise com;pression?

 

[Robert12345]

52 cub farmalsl compreession test 3 cyhlinders 75psi one was 85 pwi looked at vqlve stems all seem to be moving i die spray them with blaster going to get pqrk try to get it going thqnks for feedbqck

 

[BarnyardEngineering]

If it hasn't been run in a while those compression numbers should improve 10-20 PSI with a few heat cycles.