Merc 125 controls work for Optimax 150?

[TheWalleyeSlayer]

For you motor experts. I may have an opportunity to do a motor swap with an acquaintance. I have a 2002 merc 125 2stroke with very low hours(like 150hrs) excellent shape, etc. My acquaintance has a 2002 150 Optimax in the same shape,etc. Now you may ask why would he want to get rid of the 150? The answer is he is an older gentleman who does not want that big of a motor on his 17.5 lund fisherman, he actually originally talked about a 90hp. Anyway just to keep the naysayers at bay, there is nothing fishy about his intentions. So any way, I have an alumacraft 185 trophy with the merc 125 2 cycle. Here are my questions.

1. Would the power upgrade be worthwhile? I currently run about 35-36 wot fully loaded.

2. I here fuel and oil consumption may be less with the 150 optimax?

3. Are the controls, gauges, throttle etc, interchangeable?

4. Would this be worth a $1,000-$2,000 upgrade?

[Valv]

Controls will be same, you won't see any difference unless the Opti has SmartCraft then you might need some gauges and some of the wiring harness from the other boat.

Upgrade would ok if you keep it below the $ 2000 with installation, you will gain probably 4mph to 5 mph max, not much of an increase.

Fuel consumption is relative to usage, to keep same cruising speed you will have to "feed" the 150 a little less than the 125 consequently it will be more economical, if you raise your cruising speed since you have a bigger motor, well....fuel consumption will be same.

[camdu7]

Not sure about the controls, but I would guess you may get 10mph better plus better mpg. The opti is much better on fuel than a normal efi 2st and way better than a carbed 2st.

[marine_man]

 Originally Posted By: TheWalleyeSlayer

1. Would the power upgrade be worthwhile? I currently run about 35-36 wot fully loaded.

I think it would be - especially if you are getting the motor essentially for free. I would anticipate you'll pick up 4-5 mph like Valv said

 Originally Posted By: TheWalleyeSlayer

2. I here fuel and oil consumption may be less with the 150 optimax?.

Should be better - your going from a carb'd motor to a DFI motor - you should see an improvement there although not neccesarily dramatic -you're also picking up 25 hp.

 Originally Posted By: TheWalleyeSlayer

3. Are the controls, gauges, throttle etc, interchangeable?.

I agree with Valv here as well - unless he's got smartcraft gauges you controls should be just fine.

 Originally Posted By: TheWalleyeSlayer

4. Would this be worth a $1,000-$2,000 upgrade?.

I think so as long as you're not doing it soley to increase fuel economy / oil consumption.

[TheWalleyeSlayer]

Thanks guys for your input!!! On another note, does anyone have any idea what an average cost (labor) would be to swap those motors, as far as rigging goes?

[marine_man]

I would guess swapping both motors would take 4-8 hours total, depending on the boat (and access to connections, etc). So from there it depends on their labor rate - from $100 - $175 an hour maybe?

marine_man