Tight 2.0 engine

[safe]

Hi
I got a 2.0 69 engine that is tight, almost frozen. I need a cheater bar to turn the crank. If I turn the crank 45 degrees its loose those 45 degrees, but then tightens. If I turn it around 360 degrees I can keep turning it, but it will seize again a few days later (well, I haven't timed it).

I took the engine out of a running car but I haven't driven it very long, and just one time. It has been rebuilt by someone of unknown skill. Its built of assorted parts, mag E crank case T cylinders, T cams, unknown pistons (could be E) etc.

I'm in mid teardown, it was not tight camshafts... Hopefully I get down to piston and cylinders later this week.

Could someone take a guess what the problem could be?

[jpnovak]

warped mag case binding the crank?

[safe]

That is my best bet too.
But wouldn't it bind all the time or free up the whole 360 degrees once I brake it loose?

[304065]

"seize again a few days later"

This tells you that the mechanical clearance is changing over time

only thing that makes that happen is an organic process

known as R U S T

Rust in cast-iron cylinders.

[Flat6pac]

Possibly dry cylinders. With the cylinders up add some oil through plug holes and turn it over then reverse the side with plugs up.
Bruce

[safe]

Well, I have come this far now:




With the cylinders gone I can turn the crank by the flywheel, just a little initial sticktion.

There was oil in the cylinders, I think from previous attempts from me to lubricate the pistons.
Cylinders don't look that good, but no major rust:




I have not even wiped of the C/P in the picture above, so they look a little messy.

I'm thinking that pistons to cylinder clearance might be to tight or that the piston rings are wrong.
I forgot to mention in my first post that the oil tank magnet was full of junk...

[safe]

Think I found the problem.
The piston skirt is too tight !
I haven't the right tools to measure the pistons, but I guess the pistons aren't supposed to get stuck??
The top of the pistons fits nicely, its just the "tabs" thats tight. that is not normal is it?

[bullethole]

not normal. in all my rebuilds etc, the pistons slide in and out without much effort (rings provide the friction). but i've never dealt with a 2.0.

Just checked my new P&C's in the shop (3.0), without rings, the pistons slide nicely in and out of the jugs.