I have a 13 HP Briggs OHV 21A977-0119-E1 engine that needs rings...only about 1/4" end gap! LOL. I know I used to be able to use .010 over rings on original piston but it appears that they don't offer .010 oversize for this model! I can get .020 over...so...can I use .020 over piston rings on the original piston or will I have to get the .020 over Piston/ring assembly? Also, the max ring end gap is about .030...what's the minimum ring end gap you want with new rings? Thank you...

Hey 30YearTech? You'd know the answer to this question, wouldn't you?:wave:

You need to check the cylinder for wear. You can't use .020" oversize without boring the cylinder. I would stick with standard rings and hope that the cylinder is not worn that much. With the machine work involved and parts, it may be cheaper to get a short block or get a new engine then to go with oversize parts.

Thanks for the response 20yearTech! I've already ordered the standard rings and I'm hoping they will do the job. It doesn't appear that the cylinder walls are worn much...there's no ridge near the top which would indicate wear. I don't have my micrometers at present...didn't bring them with when I moved recently.

I bet if you check the end gap of the new standard rings, you will find them to be within reject spec. If you have no ridge then you should be alright.

Best of Luck....