Hydrocruiser

Had 21 pitch Mercury Laser II Props counter rotating on 350 Magnums on a 28' LOA Nova ST Wellcraft. Worked ok for a little while. Then had to go in on one engine because it seemed the prop would not grip and the boat would not plane. Put new rubber hubs on both. Went back out and after a few runs same thing happened again. So I switched to 21 Pitch Mirage props and it works great. What was going on? The Laser II props came with the boat. I sealed the ventilation ports as told. Why did the rubber hub keep letting go? Just curious as it's another grand out the window kinda thing.

throttleup

Most of the time when a customer complains about the hub slipping it's really the prop ventilating when getting on plane. You may just need a little cup added to the props to take care of the ventilation issue.

Every now and then we have a customer who will spin a rubber hub within a short period of time after getting on plane. This is usually caused by a lack of water flow through the exhaust which causes the rubber in the hub to overheat and fail. A new impeller usually takes care of the problem. This only applies to outboards and those with through hub exhaust.

Matt