Prop selection for a 4M Searider with Nissan 40 Outboard

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I have a 1990 4M Avon Searider with a 40HP Nissan and would like to know what diameter/pitch prop you are using with how much weight in your boat. I'm currently having trouble getting out of the hole with 3 people and a full 9 gallon fuel tank (probably partly due to the flooding bilge), but she runs strong once she is up on plane. My current prop has 2 identifying marks (P1922 and U524), but I have not been able to link that to any manufacturers dia/pitch, so I'd like to know what dia/pitch everyone is using as a starting point.

I'd like to beleive that I currently have some equivalent of the stock recommended prop (11.6 dia x 11 pitch), but can not confirm that. If I do have an 11 pitch prop, I think I need to drop down to a 9-10 pitch to get out of the hole, and give up some top end. Any thought?

Thanks,
Dave

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I believe that Nissan are the american rebadged Tohatsus so does anybody have an SR4 and a 40hp that could help Dave out?

I have a 4m Avon with a 40hp but my boat is a shallow v with a non flooding hull. I currently have a 11.5 x13 pitch prop and the acceleration is 'extreme' and the boat planes easily 6 up. Ideally I need a 14 pitch prop but my setup is alot lighter than yours seeing as you still have the flooding hull. I would estimate from the problems that you are experiencing that your current prop is a 13" or a 14" because 40HP on an SR4 is plenty (ignore olly!!) and with an 11 pitch prop you would be lacking top end. I would recommend taking your current prop to a propeller specialist or a Nissan/Tohatsu dealer and establishing what it is, you clearly need to go down a pitch.

Hope this helps

Alex