Trying to figure out what size prop I have

[Tryton]

More than a little upset with a company I just called. I need a new prop for my OMC 3.8 L and I hadn't had the old one off till today. So I call up a company I found online to help decipher and he says "Oh, it's probably a 19 pitch" and proceeded to tell me how much it would cost. I told him nowhere on the prop does it say 19 but he just kept saying it probably was. Anyway, I'm sure I can get better help here.

What's stamped on the prop is 575 13. Under that it says 505 13. Not sure if that was stamped after a repair or something but it appears to be the same lettering as the other. To the right of those it says 339 173 which I assume to be a part number. I'm guessing the 13 is the pitch and going to a 19 pitch would drastically alter performance. Any help you can give me would be appreciated and certainly better than a guess from a supposed expert.

 

[steelespike]

Re: Trying to figure out what size prop I have

We'll need more info.Read "read this first" at the top of the page and get us as much info as possible.
I can tell you a 13 would appear on a very heavy or hard to push boat.
Only 2 with smaller pitch, 10 or12 with more pitch on the list. Did you look for numbers in the area under the prop nut?
His guess was almost dead center in the list a logical guess.

 

[Tryton]

Re: Trying to figure out what size prop I have

Well, someone wrote 14 1/4 x 13 in the owner's manual so I'm assuming that's the size prop it is. I have read through the things on the site and I know 19 is in the range based on the engine. My problem wasn't the number he threw out but the fact that he seemed to be ignoring what I was telling him. I asked him why it would say 13 on it if it was a 19 and he blew me off. I'll check under the hub nut. Thanks.

 

[Tryton]

Re: Trying to figure out what size prop I have

Thank you so much! I had looked over the whole prop and missed it. When I looked more closely I could see some letters and after wiping some crud off I was able to read it. It's a Michigan 011007 which is a 17 pitch, 15 diameter. That makes more sense for the size of the boat and the engine than a 13. Maybe the stamps on the side were from repairs after all. Thanks for your help.

 

[steelespike]

Re: Trying to figure out what size prop I have

If you had some of the info in "read this first" we might be able to tell if you need a prop change as long as your needing a prop.