1976 Mercury 1150 Lower Unit Compatibility

[jtexnm]

I have a 1976 Tower of Power. I'd like to pick up another motor for parts and a lower unit in particular. What years and HP are compatible?

This is info I have searched for but I can only find newer motors on interchanges.

In particular I am wondering if some of the larger motors like 125 and 150 HP have compatible lower units. I have seen conflicting info. Does anyone know?

 

[Chris1956]

The 1500 will fit, as will the inline 4 cylinders (800, 850) from most of the 70's. The IL4 motors have a lower (2.3::1) gear ratio, than your 1150 (2::1).

Obviously the 1150's will fit from the 70's as well.

Not sure about the 125HP models, as that was either older or much newer.

Where are you located?

 

[jimmbo]

You should consider post 1979 Cases as they have improved Hydrodynamics.
Since the mid 70s, all LUs for the I6 use a 2:1 gear ratio(1972 1150 used a 25:14. maybe a typo. Then again, the 73 brochure mentions the 1150 getting a new Gear Ratio.). As mentioned above, the LU from the 66.6 4 cylinders can be used. They have a 2.3:1 ratio, which was a High Altitude Option for the mid 1980s 115hp

 

[jtexnm]

You should consider post 1979 Cases as they have improved Hydrodynamics.
Since the mid 70s, all LUs for the I6 use a 2:1 gear ratio(1972 1150 used a 25:14. maybe a typo. Then again, the 73 brochure mentions the 1150 getting a new Gear Ratio.). As mentioned above, the LU from the 66.6 4 cylinders can be used. They have a 2.3:1 ratio, which was a High Altitude Option for the mid 1980s 115hp

Interesting. I live at 7000' feet. Good to know.

 

[jtexnm]

You should consider post 1979 Cases as they have improved Hydrodynamics.
Since the mid 70s, all LUs for the I6 use a 2:1 gear ratio(1972 1150 used a 25:14. maybe a typo. Then again, the 73 brochure mentions the 1150 getting a new Gear Ratio.). As mentioned above, the LU from the 66.6 4 cylinders can be used. They have a 2.3:1 ratio, which was a High Altitude Option for the mid 1980s 115hp

Thanks, Chris. I'm in Northern New Mexico.

 

[jtexnm]

The 1500 will fit, as will the inline 4 cylinders (800, 850) from most of the 70's. The IL4 motors have a lower (2.3::1) gear ratio, than your 1150 (2::1).

Obviously the 1150's will fit from the 70's as well.

Not sure about the 125HP models, as that was either older or much newer.

Where are you located?

Do you know if a late 70's 1400 will fit?
Any idea about 80's motors? I have a couple of those nearby.

 

[Chris1956]

I would think the '78-79 1400 will fit as they are simply a rebadged 1500s. I would expect the gearcases from all the 80's inline 6's to fit, however, I did not try those.

 

[jtexnm]

I would think the '78-79 1400 will fit as they are simply a rebadged 1500s. I would expect the gearcases from all the 80's inline 6's to fit, however, I did not try those.

Do you know if any parts need be swapped? I know close to nothing about lower units so I'm open to advice. Would a Lu with a different gear ratio still plug and play?

 

[jimmbo]

Do you know if any parts need be swapped? I know close to nothing about lower units so I'm open to advice. Would a Lu with a different gear ratio still plug and play?

The ones from the 66.6 cubic in. 4 cylinders will fit, no problem. They have the 2.33:1 Ratio. It will help raise the RPM without having to use as such a low pitch prop at your Altitude

The LUs from the 3/4 cylinder Loopers will not swap over.

 

[jtexnm]

The ones from the 66.6 cubic in. 4 cylinders will fit, no problem. They have the 2.33:1 Ratio. It will help raise the RPM without having to use as such a low pitch prop at your Altitude

The LUs from the 3/4 cylinder Loopers will not swap over.

Thanks!

 

[racerone]

Your location ?

 

[jtexnm]

Your location ?

Near Albuquerque.

 

[racerone]

Sorry-----Too far away to help with a used one.

 

[jtexnm]

Sorry-----Too far away to help with a used one.

Appreciate the thought.

 

[Lhart64]

I have a 1976 Tower of Power. I'd like to pick up another motor for parts and a lower unit in particular. What years and HP are compatible?

This is info I have searched for but I can only find newer motors on interchanges.

In particular I am wondering if some of the larger motors like 125 and 150 HP have compatible lower units. I have seen conflicting info. Does anyone know?

The 1500 will fit, as will the inline 4 cylinders (800, 850) from most of the 70's. The IL4 motors have a lower (2.3::1) gear ratio, than your 1150 (2::1).

Obviously the 1150's will fit from the 70's as well.

Not sure about the 125HP models, as that was either older or much newer.

Where are you located?

I have no clue to work this forums, just signed up maybe 10 minutes ago, so forgive me for asking on another’s post but I have a late 80s (86-87 can’t remember exactly) with a 3 cylinder, 75hp. Has a burnt up lower unit and I found a lower unit for sale that came off of a 3 cylinder 75, the guy is unsure of the exact year but said it came off a 2000s model boat so I’m guessing late 90s early 00s lower unit. Will this work for my engine?