what can cause a ring to break

[Farmwithjunk]

Ether will break rings as well.

Soundguy

And a lot of those "as wells" end up in the oil pan because of ether. I'd suspect it's just as harmful, if not MORE SO, in a new or fresh rebuilt engine than in one with substancial wear.

 

[KICK]

some people shouldn't work on their own stuff

 

[BTDT]

My FIL fits that remark. I am always having to finish repairing/fixing what he started.

 

[bamatoolmaker]

If you didn't use a ring squeezer when you installed the pistons in the bores it could have broke before you bolted the head on.

 

[TrippleT]

What Diesel Power and Sully 2 and others have said is true. Another thing even using a ring compressor you need to lube the rings and then about every ninty degrees around the clamp just lightly, very lightly rap the clamp with hammer handle. NOT hard just enough to square the piston and rings, inside the clamp. Then gently push the piston into the cylinder, or use a hammer handle and drive them in gently. If you feel any resistance don't force it. If you have cylinders that are tapered the rings will flex open and close as the piston goes up and down in the cylinder. So you need to, as stated, check the cylinders at various places in the cylinders. You can do this as was stated by pushing the ring down about an inch and check the gap with a feeler gauge. Then move on down toward middle and the bottom of the cylinder, and the difference will give you an idea how much taper you have. Flexing rings can break, or lose their ability to seal prematurely because of fatigue. Of course, you should prepare the cylinder by removing the ridge and honing before putting the pistons in. It would be a good idea to find out the specs on the engine as others have stated. If you could find the specs and then get someone to use snap gauges and mike the cylinders it would let you know whether the engine worth reringing. Or whether it would need sleeves or reboring.