Engine question

[vern hodgson]

So I have an old engine sitting here, when I turn it over using a ratchet wrench, with the plugs out, it will at a certain point catch and requires a little oomph to continue turning, as if something caught or is rubbing then a little further on it catches again a requires a little more pressure to get it to continue around. Catches only those two places. This engine had been sitting for quite a few years. Any thoughts anyone as to why it would catch in two places??

[Big hammer]

Rust. Maybe in a clylinder or 2, put some oil down each plug hole.

[SeaSlugs]

does it seem to catch at the top/bottom of the strokes?

[jetmek]

Stuck valve

[daveymc29]

Pour a little Marvels Mystery Oil down all four plug holes and turn it threw a few revolutions. Come back tomorrow and repeat. Observe the difference. You will probably be amazed, yet I would still pull the head and pan to check further before trying to fire it up. Pull the dipper tray and clean out the sump and the screen on the oil pump as well as checking valves, seated and the bores.

[Kurt in NJ]

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you can look down spark plug hole and see valves---i agree it is possible for stuck valves to cause your "catch"

[Art Newland]

When the crank throws are at 9 o'clock and 3 o'clock , pistons are half way down the bores, it is considerably harder to turn. It may just be normal.

[TRP]

Would there be any harm in removing the side plate (valve cover?) to make sure all of the valves are moving as they should?

[Tom Wesenberg]

Originally Posted by TRP

Would there be any harm in removing the side plate (valve cover?) to make sure all of the valves are moving as they should?

No harm, and in fact recommended. Also oil the valve stems through the side holes if the manifolds are off.

[Mike V. Florida]

How about a little more information to help us with our guesses. When does it "bind"? Is it in the same place every rotation, every second rotation? As different things happen at different places as the different parts rotate knowing when it happens can tell alot before you even open up the engine.

Can you find the timing dimple? Starting there and keeping track of when in the rotation you feel the bind we can deduce that is happening at that time with the moving parts of the engine.

[100IH]

All good answers.

[Gold Digger]

I've had carbon turn loose after setting for a long time. Could be some piled up on top of a piston or two. If it has laid on the drivers side a good possibility.

[vern hodgson]

Originally Posted by Mike V. Florida

How about a little more information to help us with our guesses. When does it "bind"? Is it in the same place every rotation, every second rotation? As different things happen at different places as the different parts rotate knowing when it happens can tell alot before you even open up the engine.

Can you find the timing dimple? Starting there and keeping track of when in the rotation you feel the bind we can deduce that is happening at that time with the moving parts of the engine.

I will do that first thing Sunday morning and let you know, thanks.

[BILL WILLIAMSON]

And after you've listed ALL the possibilities, ALPHABETICALLY, you tear it down to BARE BONES & find it wuz something "OFF THE WALL" that you never heard of---NLOL
Bill W.

[vern hodgson]

Originally Posted by Mike V. Florida

How about a little more information to help us with our guesses. When does it "bind"? Is it in the same place every rotation, every second rotation? As different things happen at different places as the different parts rotate knowing when it happens can tell alot before you even open up the engine.

Can you find the timing dimple? Starting there and keeping track of when in the rotation you feel the bind we can deduce that is happening at that time with the moving parts of the engine.

So I started doing that, each time it caught there would be a deep solid clunk. It caught at 1/4 revolution, then at 3/4. Then I squirted oil into the cylinders (don't know why I didn't think of that before, two or three revolutions it smoothed out considerably. Ergo, it could have just been no lubrication on bare metal moving parts sitting for years. Thanks for the advice from all.