I think you are going to be ok with those ring gaps I did a very fast rebuild on my 2003 mercury 125 3 years ago and I only put in new piston rings on the motor and a used standard piston from ebay for cyl2 which was blown and the motor is still running strong to this day without problems my piston ring gaps after honing all the cylinders were cyl1 0.31 cyl2 0.49 cyl3 0.36 cyl4 0.29 and the compresion after the rebuild was cyl1 135psi cyl2 125psi cyl3 135psi cyl4 138psi as you can see they are within less than 15 psi difference on all the cyl just put some new rings on those pistons and run it hard you do not want to spend that amaunt of money on an absolite motorOk so after honing I measured tye end gap on all 4 cylinders and 1,3 and 4 have .016 throughout while the one I had to hone deeper is .035. So .019 difference in gap
#2 measures 3.3820 now.
Otherones at 3.375 now
Thanks but this has been fully rebuilt, machine shop, new pistons, rings all .20 oversized. I am at the broken carb tab, studder when running, bought another flywheel for good measure. When I took the old one off I heat it up and had to hammer it, so I don't know if the magnets were affected in any way to cause the hesitation when running. Am exploring possibilities so I can get this damn thing on water already. All my friends are making fun of me hahaha we celebrated a year since I bought it last year, without actually fishing from it.I think you are going to be ok with those ring gaps I did a very fast rebuild on my 2003 mercury 125 3 years ago and I only put in new piston rings on the motor and a used standard piston from ebay for cyl2 which was blown and the motor is still running strong to this day without problems my piston ring gaps after honing all the cylinders were cyl1 0.31 cyl2 0.49 cyl3 0.36 cyl4 0.29 and the compresion after the rebuild was cyl1 135psi cyl2 125psi cyl3 135psi cyl4 138psi as you can see they are within less than 15 psi difference on all the cyl just put some new rings on those pistons and run it hard you do not want to spend that amaunt of money on an absolite motor