Mercury 75 HP FourStroke Prop

[fishon396]

Thanks for your time and help.

[gatorglenn]

When the nut is torque right. There is a 1/8-3/16" play in it. Forward and back, but not side to side. This is normal for a flow-torque system.

[fishon396]

Glenn that is what I was hoping to hear. I have less than 1/8" front to rear with a dial indicator and no side play. Thanks

[Deerchaser]

I have about 1/16 of end movement.

Glenn that is what I was hoping to hear. I have less than 1/8" front to rear with a dial indicator and no side play. Thanks

[fishon396]

Thanks for checking it's time to go fishing.

[Deerchaser]

Let us know how the new prop does compared to your old one. Good luck!

Thanks for checking it's time to go fishing.

[ttourikis]

Been online reading different prop. top ends on a 175TXW. Some guys are claiming 49mph on the gps with a Vengeance 48-16988 18P on a 75HP Mercury 4 stroke.

What do you guys think????

[ttourikis]

Also, motor is moved to the third hole down.

Been online reading different prop. top ends on a 175TXW. Some guys are claiming 49mph on the gps with a Vengeance 48-16988 18P on a 75HP Mercury 4 stroke.

What do you guys think????

[gatorglenn]

The only way they could reach 49 with that set up. Is to have a prop that is a pitch to high. take a very long time to get on plane and have the boat very empty like only one battery. Realistically you're looking at 41 to 43 as a bitch Mark to reach but typically fishing loaded down your only run 39 to 41.

[ttourikis]

The only way they could reach 49 with that set up. Is to have a prop that is a pitch to high. take a very long time to get on plane and have the boat very empty like only one battery. Realistically you're looking at 41 to 43 as a bitch Mark to reach but typically fishing loaded down your only run 39 to 41.

I agree, I thought 49mph gps for a 175TXW with a 75HP was way too fast. What do you think about the motor mounting position?

[gatorglenn]

For the 75 and 60, this hull does best mounted in the 2nd hole down from top. 115 hp on 190 hull seems to be best in 3rd hole.

[Deerchaser]

Agreed!

For the 75 and 60, this hull does best mounted in the 2nd hole down from top. 115 hp on 190 hull seems to be best in 3rd hole.

[ttourikis]

You guys are the bomb.com!!!!

[onrecess]

When I used the mercury prop selector, they recommended a 12.76 x 21!! 21? I used weight 1010 (pt 175 txw per tracker specs), and 400 lb people and gear, and good overall performance. Crazy. The max pitch they make is 21, and it is for 75-115 4s.
So, what is the performance difference between a Spitfire (alum allow) and Spitfire x7 (stainless?) The prices are 160ish and 450ish, a 300 dollar difference. Would you use the same pitch on both? (17)?
Thanks

[gatorglenn]

The aluminum prop is much lighter. And the blades will flex some. Because of this, ss props are usually a pitch lower. There is no flex and more weight for the motor to spin.

Those recommendations are a range, according to how much weight you have in the boat and how it is set up with that weight. I know a guy who has a 60 run in a 16 inch prop on a 15 1/2 foot boat and it will do 45 miles an hour. But on these boats with the weight we typically have in them. 17p for 75hp and 19p for 115hp. Tha 90hp seems to be the one that has a problem finding a good match, with needing prop work done to find that match.

[onrecess]

Thanks, you really seem to know your stuff!

[Deerchaser]

Thanks, you really seem to know your stuff!

Glenn is da man! Has helped me.

[Lowerider58]

When I used the mercury prop selector, they recommended a 12.76 x 21!! 21? I used weight 1010 (pt 175 txw per tracker specs), and 400 lb people and gear, and good overall performance. Crazy. The max pitch they make is 21, and it is for 75-115 4s.
So, what is the performance difference between a Spitfire (alum allow) and Spitfire x7 (stainless?) The prices are 160ish and 450ish, a 300 dollar difference. Would you use the same pitch on both? (17)?
Thanks

If the 1010 weight is for just the hull you would need to figure for the motor, TM, batteries, fuel, gear and passengers.

[Deerchaser]

If the 1010 weight is for just the hull you would need to figure for the motor, TM, batteries, fuel, gear and passengers.

Prop selector is way off, better off with real woeld experience.