I have a 20" reel mower with four wheels which I got second hand. I have sharpened and adjusted the blades so that they cut well, and replaced the pinion gears, which were worn and making the wheels stick somewhat. However, I still can't seem to get it to stop flipping forward when pushed. The rear wheels jump up off the ground and the whole thing rotates forward, and then it stops moving well. The only way I can stop it from flipping forward is to push it with the handle at a lower angle, but this is uncomfortable, and I'm only 5'7".
Lubrication is key to all moving parts, especially parts made from metal. Did you apply grease to pinion gears upon assembly? Make sure parts are clean from dirt, old grease, etc. before applying new grease. I clean my steering sector & pinion gears each service then inspect gears for wear & apply new grease to both gears.
