Getting a new lower unit to install on Yamaha 250 HPDI and was curious about break in period. I've heard some say you don't need to break them in and others say you do. Just looking for y'alls advice or experience with this.

I have never broke one in. I broke 15 or 20. Fill it with oil. Idle out and get on it. If it going to break taking it easy on it will not matter.

You don't have to break in a OEM gearcases. Some after market or reman. my require break in. Follow the instructions with the lower unit.

Thanks Bruce and Tommy for the info. I will definitely look at the info that comes with the LU. Tommy, Do you know anything about OBR lower units out of Alabama? Obviously it's a reman just curious if you have any experience with them or know if they require break-in. I know the SEI's do.

OBR make s good product. We use them when we can't get a factory reman. for our customers. Very few issues with their product. I honestly don't remember if they have a break in or not. I will have to check on that.

Thanks

changing the gear oil after 10 hours will make sure any break in particles get removed. a magnetic lower drain plug is a good thing too.
most important dont grind the gears while shifting,. shift crisply, dont pussyfoot around. dont ease into it get, one quick motion . if not the gears will wear fast, and the more they wear, the faster they wear.
One cluck is all you should hear.