Mercury 150hp Mounting measurement

[Extra 260]

Could some give me a meausurement fom the lower transom mount bolt to the center of the prop on a mid eightys 150hp Merc. Let me know if you have a 20" or 25" shaft motor.<br /><br />Many Thanks

 

[Reel Appeal]

Re: Mercury 150hp Mounting measurement

Extra 260,<br /> I'm a little confused. Are you looking for the correct size outboard for your boat or just looking for a Merc 150 outboard?The size is measured from the inside of the transom(motor)bracket down to the cavitation plate.Or,you can measure the transom center from top to bottom for an approximite size.The cavitation plate on the motor should be in line(or slightly above)the boat bottom.I hope this is what you mean...?

 

[Extra 260]

Re: Mercury 150hp Mounting measurement

I know that I have 11" from the bottom motor mounting holes to the bottom of the boat. I was trying to figure out if I buy a 150hp Merc with a 25" shaft how much I will need to raise it to make it work (how much jack plate it would need). I hope that makes sense?<br /><br />Thanks

 

[Reel Appeal]

Re: Mercury 150hp Mounting measurement

Find the closest shaft length to match the transom height.Then jack it up from there(if necessary).Measure the transom height and post back.

 

[Extra 260]

Re: Mercury 150hp Mounting measurement

My transom measures 20". So am I to assume that If I get the 25" Merc that I would need to raise the motor at least 5"?<br /><br />Thanks for your help.

 

[rickdb1boat]

Re: Mercury 150hp Mounting measurement

Not to butt in, But Yes, that would be correct.

 

[Reel Appeal]

Re: Mercury 150hp Mounting measurement

Extra 260,<br /> Your assumption is correct.Why not get a 20" motor to better fit the boat?The idea of a transom jack is to raise the prop slighty out of the water at high speeds,therefore giving less drag.They are usually used for high performance race boats and the like.Is it a race boat of some type?If you are mechanically inclined you could also get the 25" motor and find a 20" leg, driveshaft,shift rod,(cut down the water pump tube)making it a 20" motor.The driveshaft should be easy enough to find,the leg may be a little more difficult.Good luck.

 

[Extra 260]

Re: Mercury 150hp Mounting measurement

Hey I realy appreciate all the help. I am an airplane guy trying to break into a new hobby. I bought a 17'6" bass boat a year and a half ago and am finally getting around to putting a motor on it. I fell into a nice 150 Merc that has the long shaft. I am sure I could put the 20" shaft on it. Maybe that is how I will proceed. Again thanks for all your help!

 

[Hooty]

Re: Mercury 150hp Mounting measurement

The distance from the bottom mounting holes to the bottom of your boat has no bearing whatso ever on the shaft lenght of the engine.<br /><br />c/6<br /><br />Hooty

 

[Extra 260]

Re: Mercury 150hp Mounting measurement

Hello Hooty, I just new that if I knew that measururement on a 25" motor I could figure out high of a jackplate I would need roughly.