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Mark Hayes

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" Hello everyone,
Just a

" Hello everyone,
Just a simple question. I have a 1974 17' tri-haul ST-170 with a 85hp Johnson outboard. I am told that they are notorious for (pushing water) being heavy. I dont know my pitches for props, but understand the concept. I want to take a skier or pull the kids. As it stand right now it takes a while to get to top speed (with more than two or three onboard). I am assuming that the prop is set for speed and not pulling power. What would be a good place to start, as far as pitch goes, to pull a skier? Or maybe its a tilt issue any ideas? "
 
" If you can find some to let

" If you can find some to let you try some ,Try the 15 pitch and see if that won't bring you out of the hole quicker. Look on the prop and see what you are useing now
The smaller the pitch the quicker out of the hole. It will let your motor get up to rpms quicker "
 
"This site lists various OMC p

"This site lists various OMC props and their suitable applications. http://theoutboardwizard.bizhosting.com/v_4__props__60_140hp.html

Also, you can modify a higher pithed prop to perform better out of the hole. You can drill 5/16" up to 1/4" holes on the leading edge of the blades to allow exhaust gas to vent over the blades when you take off. This allows the blades to slip in the water and get your RPM higher faster, thus getting more power quicker.

Also, power Tilt & Trim is a must. If you don't have this, look into getting it. If your motor is pitched up for cruising, it is expending far too much horsepower on your holsehot trying to lift the bow rather than getting up to speed."
 
" Oops, I meant to say you can

" Oops, I meant to say you can drill 1/8" up to 5/16" vent holes. Sorry, my brain cut out for a few moments "
 
Thank you I will try that. No

Thank you I will try that. Now you do meen the exhaust and not the fins of the prop right?
 
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