Replacing 85HP Force w/ different outboard

[playyas4u]

Hi, I am wanting to replace my 1989 85HP Force with a different outboard and was wanting to know which brand outboards would be the easiest replacement. My Force outboard is on a houseboat therefore all my cables are about 30' and I would like to reuse what I have if possible. If that is not possible what all would I have to replace to put a new outboard on? I was thinking about switching over to an Evinrude or Mecury but would be open other options if it would be an easier swap. Thanks for any advice in advance.

 

[roscoe]

Any replacement would involve the same amount of upgrade/work.

Motor (obviously), wiring harness, throttle and shift cables, and controls unit.
Wiring harness could be costly, depending on length.
Cables "may" possibly be saved if a generic cable with replaceable ends, but don't count on it.

Steering cable should be useable, probably needing a new drag link.

And you will need to drill new BIA standard transom bolt holes to mount any newer motor. And plug/seal the old holes.

 

[bruceb58]

If I was replacing an engine with a new one, the first thing I would do would be to replace the cables and likely the shifter too!

 

[jerryjerry05]

Unless you keep the same motor.
Up till the mid 90's your gonna need to drill new holes.
Then the shifter, cables, and maybe the wiring harness will need to be replaced.
You'll need a key switch too.
Tach too.

Might be easier to just fix what you got.
If you need more power?
Get a 125 or a 150 Force.
Both will bolt right up.
Just make sure they are the right length.
They come in a 20 and 25 inch.

 

[playyas4u]

Unless you keep the same motor.
Up till the mid 90's your gonna need to drill new holes.
Then the shifter, cables, and maybe the wiring harness will need to be replaced.
You'll need a key switch too.
Tach too.

Might be easier to just fix what you got.
If you need more power?
Get a 125 or a 150 Force.
Both will bolt right up.
Just make sure they are the right length.
They come in a 20 and 25 inch.

I think I may just go this route and find me a 125 or 150 Force. So will it be as simple as unbolting the old force and bolting the 125 on, will all the same cables & wiring work? Also what years should work with my current engine? Thanks.

 

[playyas4u]

No Title

I think I found a 125 that will work...I can't tell if both are 20 or 25 inches in length as I am not at my boat and I haven't went to look at the 125 yet. Can anyone tell from the pictures if this will work? If they are different lengths, can I just change the foot from my 85 to the 125?

 

[Jiggz]

From the pics, they look identical in length. And yes, if you decide to swap it is virtually plug and play with all your existing accessories. And if the LU on the 85 is fully functional, you can get additional performance by using it with the 125 head.

 

[playyas4u]

Why will the lower unit off the 85 give the 125 more performance? Also are any of the 85 HP parts compatible with the 125 in case it needs some work? Thanks for your help.

 

[jerryjerry05]

It looks like the new motor has a long shaft.
You need to measure the housings and see.
The rear cowl or cover just below the crud/water line.
Measure to the cavitation plate.
Measure both I think you'll find the new is 5in longer.
The motor is a direct swap if it measures up.
If not, everything from the powerhead swaps.
The trim/tilt works too.
There is a difference in gear ratios but you don't need to worry about that.
Pushing a house boat you'll need the lowest pitch you can find.
I saw a 13p but not sure they still make one.
Contact Michigan Propeller.

How much for the new 125?
The parts are worth the price if it's cheap. The lower unit with the long shaft is a big selling item.
They don't make em anymore so the parts are worth the buy.

 

[playyas4u]

So if they are different lengths then I can't use it or I just have to swap out the foot? The motor hasn't ran in a couple of years so I am guessing I will probably have to do some maintenance to get it up and going. They guy said the 125 had issues going from reverse to forward gear the last time he took it out but thought it was something to maybe due with the shifter cable. I will check the compression to make sure they are with in specs, other than that anything else I should look for? Also what compression should the 125 have? I am getting the 125 for $300.

 

[jerryjerry05]

The shifter? Check the oil in the lower unit..
Then unhook the connector and try shifting as you turn the prop with your foot(motor off).
Your lower won't fit on the newer motor if it's a different size.
The powerhead will fit and all the electronics will fit except the trigger.

What's wrong with your old motor?

The compression should be all about the same.
Mine are all about 145#
Yours might be the same or even more.
Your looking to get a reading where all are about the same.
Within a couple pounds of each other.

Your gauge might read different than mine.

And for $300 it's still a great buy.

I'd buy that all day long!!

 

[playyas4u]

So, if the motor is 25" and mines is a 20" will it work for my boat or can I make it work by just swapping the power head over to my motor. There's nothing wrong with my 85, I just want more power. I will probably fix the other boat up and sell it with my 85 hp on it.

 

[jerryjerry05]

Yes a powerhead swap will work.
You measure the stuff? It sure looks like they are different sizes.

All you'll need to swap is a base gasket and a tube of black silicone.

What pitch prop is on the boat now?
How many RPM's at wide open?(With a clean bottom).
That scum on the bottom will slow you down and drop the rpm,s.

If your over propped that will actually slow you down and you'll spend more in fuel.

 

[playyas4u]

I bought the Force 125 and took it to the mechanic. The mechanic says that everything looks good except that the motor is stuck in forward gear and that I will need to have the carbs cleaned which I expected. The question now is should I pay him to break the lower unit down or should I just swap the power heads out? He seems to think that I can not just swap out the 125 hp head to the 85 hp motor??? I guess my question is what are my options with the motor being stuck in forward gear? If I do the power head swap is it even necessary to have the carbs done on the 125 or can I use the carbs on my 85 that were recently rebuilt?

 

[jerryjerry05]

Different carbs altogether.
Just replace the power head.
Maybe something simple in the lower?
Might just be a stuck shift rod?
The mechanic should know why it's stuck in gear??

Remove the lower and see if the powerhead turns over?

Hope you didn't buy an anchor.

 

[playyas4u]

The power head is good. He tested the compression and spark. I guess I may get him to check out the lower unit as well and just swap both power heads & sell the 85 HP. How many hours should I expect to pay a mechanic to swap out the power heads and which gasket do I need?