How Much Resistance to Crank Start the Engine?

[FarmallCubGal]

On a perfectly working 1948 Cub, how much resistance should I feel when starting it with the crank? Thanks

[Denny Clayton]

Not so much, Lisa. Even with compression of 100-110 psi that long crank spins easily.

[Jim Becker]

There should be a very notable increase in the force required each 1/2 turn as a piston comes up on compression. If you don't notice the change as it rotates each 1/2 turn, something is wrong.

[Eugene]

Not a lot of resistance. Never measured the resistance, perhaps 10 or 15 lbs.

You can roll the engine over by pulling/turning the fan.

[staninlowerAL]

Worn rings will reduce the resistance. A compression check will help you determine the condition of the engine. Probably need to adjust the valve lash as well. As been previously stated, a Cub will run very well with worn rings, just won't have a lot of power--(new, straight from the factory it was less than 10 hp).

[AL Farmall Boy]

and stuck valves Stan.....

[Matt Kirsch]

With only 60 cubic inches, and only 15 of those coming up on compression every stroke, like everyone else has said, not much.

My addition to the conversation is this: Even though it spins easily, resist the urge to "wheel" on the crank as if you're winding up a jack-in-the-box. The engine can still do damage to thumbs, wrists, and shoulders if it were to backfire and the crank catches in the front pulley.

[k hutchins]

I was taught to crank my '48 when I was 10.
Rule #1 keep your thumb (if right handed) behind the handle, basically palm and fingers only incase of kick back
Rule #2 you don't need to "wheel" it, you really only need a half revolution if everything is working the magneto clicks twice every revolution, so if the coil and mag are good you only need a half turn.

It takes some practice, but it's easy enough that I crank started mine for a year because I was too cheap to buy a new battery.

[LRiddle]

Lol. I learned the hard way not to grip with the thumb. I was lucky though and it was only sore for a couple days. Just enough to knock sense into me to do it the right way.

[Glen]

Hi,
Here is a page from a Cub owner's manual showing how IH recommended to hand crank the engine. It is at the bottom left, there are some instructions at the word "Caution" there.

http://farmallcub.com/rudi_cub/www.clea ... age-09.jpg

[Jim Becker]

OK, since this thread has shifted from "how hard" to "how":

viewtopic.php?f=1&t=57127