Prop and motor mount height question.

[npd568]

hey everyone, i bought a 2004 Nitro NX750 hull that I have been fixing up with my son. I have purchased a 1999 Mercury 90 ELPTO to go on it. Im getting ready to hang the motor on the back so I can get it to the shop to have the engine gone through and ready to go for spring. However, I have no idea on engine height or which holes to mount the engine in. The engine also did not have a prop on it when I bought it as well. Im wondering if anyone here can give me some advice on which holes to mount onto the boat and best prop for that engine and boat. Maybe a long shot but im kinda lost.

 

[cceguy]

If you can tell which holes on the engine were used before, and they line up with the transom holes, that would be a good start. You can start with the anti-ventilation plate parallel and even with the bottom of the boat, and make adjustments from there. A jack plate is a good investment.

Some prop dealers will let you test-drive props before you buy.

 

[npd568]

well the motor came off a pontoon. So idk if they would have mounted it in the same holes that I would want it mounted on a bass boat. Ive searched several articles and I think im going to start in the middle or second one from the top. Still no clue on a prop yet lol.

 

[Pat Dilling]

If you are taking the rig into a shop to have the engine gone through I would consult with the shop mechanic. An experienced shop should be able to give you good advice on engine height and prop choice.

 

[maybrfd]

With your serial number you can most likely get the original installation manual from the Mercury website and or other download sites on the web. If you're going to have the engine torn down anyway by a merc mechanic, you might trust that individual to install it as well. While install is straightforward, there are a few tricks, which those in the know, can make a difference. Good luck with the restore!

 

[npd568]

I have the shop manual for my engine however Mercury states they do not advise on mounting engine height and props as all hulls are different. So I contacted Tracker Marine and got no help there either.

 

[maybrfd]

Send me a pm and I'll see if I can share a manual that should get you in the ballpark

 

[byron cooley]

I have a black max 13.5x19 prop used one day trip on my nitro 640LX 75 optimax if interested. Not a scratch in it

 

[Chuck]

The Mercury motor that was on my pontoon boat had a longer shaft built just for pontoon boats.

 

[npd568]

This engine has a 20” shaft so I’m all good with the length.