I agree a larger, slower turning blower would be an easy HP increase.
If you want to keep the 177, I would send it to Darren Mayer Performance Engineering. These guys do a great job at a reasonable price. www.dmpeinc.com
Regards,
Steve

I think its around $350-400 plus parts to get them rebuilt. Also some of the parts for the Merc 177 are no longer available. I know the front shaft where the pulley mounts is NLA. If it is bad, you would be better off looking for a good used 250 blower which would be less $$$.

And Dang.......................those batteries must be 8-10 years old.

Ditto on Darren Meyers Perf ,we send bryan a dozen blowers a year and always fast service & reasonable :drink::drink:

thanks guys!

Yes Griff they lived a good life and we tried for one more year but it was a no go. I put them in all by myself too! We also had to have some bottom work done on her. She had a huge soft spot but got that all fixed. Thinking I may put on my other higher geared drive next season. I have a pretty big leak and not sure that it is coming through the drive. She is a good girl and I LOVE her!!!

It probably needs bellows. I doubt the higher geared drive will help anything. In most cases you don't switch unless you are out of prop pitch.
To go from a 1.5 to a 1.36 you need to drop about 3" in pitch to get the same rpm.
Sorry to hear about the soft spot.