prop ID help

[71ghia]

hello all i just purchased a used boat. fixed a couple things ad have it running on the water fine now. it has a force 90 engine and at wot will only get up to about 4500 rpm and maxed out at 28.8 mph with a GPS. i know this thing can get up and move faster but need help with prop ID. this is my first boat so i dont know much about anything lol. the numbers i got off of the prop where hard to see and painted over 48 77346 either an A or a 4 45 19 P

 

[Silvertip]

Re: prop ID help

The 19P at the end of the string of numbers is the pitch of the propeller. 19-inches in this case. You can measure the diameter by measuring from one blade tip to the exact center of the prop shaft and multiply by 2. A 19P prop seems appropriate for a 90 HP engine. Your engine needs to be in a proper state of tune to perform as it should. If the boat is full of water soaked foam you are dragging around a couple hundred extra pounds. If the engine is tired it can't deliver full power. Do a compression check.