Hello – I’m really hoping to get some advice on how to pull the balancer and oil pump drive gears. The Yamaha service manual just says "pull the gears", which doesn’t help much.

Background: 1999 Yamaha Big Bear 350 4×4. I’m rebuilding the engine for my brother-in-law. The crankcase needs replacement due to broken starter idler shaft mounts.

I’ve rebuilt many motorcycle engines, and I’m fairly close to separating the cases on this 350, but I’m concerned that I’ll break the balancer and oil pump drive gears. The gears won’t budge with the puller, and I’ve gently heated the gears a bit to try and break them free, but no luck.

Since this is my first post, the system won’t allow me to add a photo – says I need 10 posts first. Darn. I’ll try to get the picture up asap.

Any advice? I didn’t see any of these engines being pulled apart on YouTube, so I thought I’d see what the experts out here recommend. Any comments/advice are appreciated.

Thanks,

Kevin