hello i have a merc 70 three cyl two carb, i put new rings in it and had it honed, pretty much ever thing has been replaced including the stator, the problem with these is the top cyl any mechnic knows about these motors so she runs great 135 top to bottom with compression after break in, im running about 35;1 fuel mix ams oil and i got the top carb backed off about three turns from seat and the bottom is about two and the middle and bottom cyl looks great little bit of pooling on the bottom of the plug u take the top plug out look in the cyl very little pooling on plug and the rib thats on the piston is super dry u look at the rib on the bottom two cyls wet with gas, any old timers or mechnics who have master these motors let me know thank u 