Tohatsu M5B troubleshooting assitance

Hi,
Last year I picked up a RIB with a mid-2000s M5B on it. I don't have a lot of experience with 2 stroke engines but it seems to run a bit rough and smoke a lot more than I expected. While it does smooth out at higher RPMs it doesn't seem as smooth as other low-HP 2-cycle engines I've used.

I drained the fuel, ran it dry and refilled it with a 50:1 mix using TCW3 2-cycle oil. I also put in a new spark plug.

I don't see any change in operation.

I posted a short video on youtube of the engine running so you can see what is happening. Can you tell me if this is normal or what I should look at repair-wise?

Link: https://www.youtube.com/watch?v=hG8HPuOSrUE


Thanks.

Pretty typical. Idle sounds a little slow. You could decarbon it and see if the smoke improves.

Thanks pvanv. Based on that I'm not going to do anything major to it before this season. Any idea where I can get a factory service manual? I have the owner's manual but it's not much help in planning out future repair work.

Any Tohatsu/Nissan dealer (even me) can get one to you. Drop me an email: [email protected] and I'll be happy to help you.