prop prblems

[tradhunter]

I have a 2000 mdl f50tlru yamaha outboard mounted on an 18' river john. At WOT and trimed out it is only running 5-5100 rpm. I was told that it should run between 5500 and 6000 rpm at wot. I got the # off the prop and it is mich wheel 992404 11p. So I figured I would order a 9p and fix the problem. but when i resurched the prop it is a
10 3/8 X 11p prop. The prop chart for this motor dose not even show a 10 3/8 prop. can any one tell me what prop I need on this boat. THANK YOU

 

[steelespike]

Re: prop prblems

Welcome,
The diameter is a secondary consideration.
Any prop listed to fit your motor will work.For more predictable results I would stay within say a 1/2" diameter either way.Now as to the prop you need to make up 900 to 1000 rpm to get to 6,000 max rating. I think you either have a tach issue or a motor performance issue.
If you read the stickies at the top of the page and get us as much detail as possible it will help us determine how well your setup works.