Who’s at fault for wrong prop on new Merc?

I had a good friend call me over the weekend with a question about lower units and props.
In brief, this was his problem: He has a 2005 Ranger Reatta with a 150 Opti. He purchased the rig new in the spring of 2005. The motor came with a high 5 prop. He was never overly impressed with the performance, 46-47 was his top speed in and at times he could only hit 44 mph in mid summer. In the spring of 06 his lower unit went out and his dealer replaced it with used lower unit from another Opti they had in the shop. Last fall he moved to another town and brought his boat in for service at the local dealer. He got a call Friday telling him that the prop on his boat did not have the right hub size. Apparently the prop the boat came with has a small hub. The dealer told him there is a ½-3/4 inch gap around the outside of the hub. The new local dealer told him this was causing exhaust to blow out around the prop and not allowing the prop to get as much bite as it should normally get. My friend was wondering if there could have been two different lower units on these motors and when his was replaced the hub size changed? If not, who is responsible for the prop that is put on the boat? Does Ranger install the props, or the dealer? Now that he has had the boat for three years, is there anything he can do to get the right prop without it coming out of his pocket?

The new motor would have been shipped with a prop. Probably a 3 blade aluminum.

The dealer probably put that prop on that boat because it performed well for another customer.

Keep in mind that putting a small hub prop on that motor is not “wrong”. Having some exhaust gas blow over the blade can improve performance on many boats. Not uncommon at all on bass boats.

Take the Hi-5 and sell it. Go to the dealer and figure out what prop works best for that boat and load. It may take 5-6 different props before you find the “Best” prop for “His” situation. A good Merc dealer will have demo props for you to try out.

Bottom line, I don’t see anyone at fault. If he didn’t want a Hi -5, he should not have paid for it. That’s a $650 prop new.

Good Luck,

-J.

No real “fault ” I guess. The gearcase going bad… – not likely due to the prop. I run a similar set up on a Ranger with a 4-blade with a smaller diameter barrel than the nosecone on the gearcase. This alows exhaust at holeshot to travel on the outside of the prop to “cavitate” slightly (raise rpm’s ) thus good holeshot. Up to running speed the exhaust travels through the prop just like any other prop. Perfect set up for me – the walleye guy may hate it , thats why there are so many set-ups out there.

V-6’s should have a 14″ hub and V-4’s 13″( large and small) , I dont think you could even swap them back an fourth – I never tried it.