!988 Mariner Magnum II 150HP vs 1978 Mercury Black Max 175HP

[ventureman]

Hi guys, I just bought a new to me 1988 Ranger 375V with a 150HP 1988 Mariner Magnum II motor. Starts shifts and idle real good in a test drum. Previously ran a 19 foot Venture Phase V with a 1978 Mercury Black Max 175HP motor until I blew the motor. Replaced motor with a 1977 inline6 150 HP Mercury but never get to used it since I primarily fish in my partner' s boat or my 16 foot aluminum boat with a 40 horse on it. I still have the Black Max, and from what I can tell, a lot of the parts are the same. If a lot of parts are interchangable, I plan on keeping the Black Max for parts. Everything is in great ship except the powerhead on the Black Max. However, I do noticed the lower unit is smaller on the Mariner. If I ever blow a piston on the Mariner, are the piston on the Merc the same size? Just wondering. I think the Mariner is a rebadged Mercury XR4. One more question? The trim tab on the Mariner has been removed, because the prop would hit it if it is there. Anyone here run a motor without the trim tab?

 

[j_martin]

Re: !988 Mariner Magnum II 150HP vs 1978 Mercury Black Max 175HP

Hi guys, I just bought a new to me 1988 Ranger 375V with a 150HP 1988 Mariner Magnum II motor. Starts shifts and idle real good in a test drum. Previously ran a 19 foot Venture Phase V with a 1978 Mercury Black Max 175HP motor until I blew the motor. Replaced motor with a 1977 inline6 150 HP Mercury but never get to used it since I primarily fish in my partner' s boat or my 16 foot aluminum boat with a 40 horse on it. I still have the Black Max, and from what I can tell, a lot of the parts are the same. If a lot of parts are interchangable, I plan on keeping the Black Max for parts. Everything is in great ship except the powerhead on the Black Max. However, I do noticed the lower unit is smaller on the Mariner. If I ever blow a piston on the Mariner, are the piston on the Merc the same size? Just wondering. I think the Mariner is a rebadged Mercury XR4. One more question? The trim tab on the Mariner has been removed, because the prop would hit it if it is there. Anyone here run a motor without the trim tab?

It's the same as an XR4, which is a 2.4 head over a 4 1/4 inch LU. That makes it a little slipperier cutting through the water.

They don't have a trim tab on them because most of them are run with the tip of the prop piercing the surface anyway. If you look close, you'll probably see a barely visible starboard bend in the trailing edge of the skeg.

They are mean, fast, tough little motors if you take care of them. Run the high performance LU lube in it. Keep the LU in good adjustment, especially if you surface the prop. Run it near the high end of the power band, up to 6000 rpm. It is probably a bit stronger and faster than the '78 175 motor.

The 78 may be a 2.0L engine, which would have smaller pistons. I'm not sure, though.

hope it helps
John

 

[ventureman]

Re: !988 Mariner Magnum II 150HP vs 1978 Mercury Black Max 175HP

Thanks for the insight John. I will let you know how it runs once it's on the open water, hopefully in a couple of weeks. I am just so excited about owning a Ranger. I told my wife that if you saw that Ranger into 2 halves, it would still float. Myth or legend? (to justify the cost) Anyone?

 

[j_martin]

Re: !988 Mariner Magnum II 150HP vs 1978 Mercury Black Max 175HP

Thanks for the insight John. I will let you know how it runs once it's on the open water, hopefully in a couple of weeks. I am just so excited about owning a Ranger. I told my wife that if you saw that Ranger into 2 halves, it would still float. Myth or legend? (to justify the cost) Anyone?

I've seem them hit a log and rip the transom clean off, and still float, but don't tell her that.

Most modern bass boats have enough floatation in them to keep any major part left on top to cling to.