1999 force 120 hp

[PETE BUTZEN]

Good Evening : I could use some positive ideas on top performance on a 1999 force 120 hp on 1999 trophy 2002 , need power in rough water . currently running 100 octane frequent plug change / not neaded , running a 13.25 /19 pich 4800 rpm loaded and in rough seas . Only time she will runout on plane is when flat seas and running light . motor has only 200 hrs . What do you guys think ? would a 4 blade prop help ?

 

[jerryjerry05]

Re: 1999 force 120 hp

No on the 4 blade. If 4800 is all you can get then go down from the 19 to a 17, maybe even a 15??
You'll find more response and better fuel economy.The 19 will get you going a bit faster also a bit more expensive 15-25% more expensive?.
Don't need 100oct. They were designed to run on regular pump gas.
Do a compression/spark test.
Remember it's only a 120hp motor. Not gonna break any speed records.
How much stuff do you have in the boat? To much stuff hurts performance. Get ride of the extras, you only need 1 life jacket per person. get rid of the extra coolers and don't run with the whole neighborhood??
Full gas tank? You really need all 60 gal. or what ever fits in your tank. My tank is 100 gal. That's about 800#s I hardly ever use more than 25.

 

[roscoe]

Re: 1999 force 120 hp

Fully loaded, your boat is close to 3800#. plus passengers.
THe 120 hp Force is not likely to do very well.

Boat is rated for 175hp.

Nice boat, but needs more power.

 

[Frank Acampora]

Re: 1999 force 120 hp

To paraphrase the line in JAWS: You're gunna need a bigger engine! A 5 cylinder Force 150 should bolt up nicely and give just a little extra oomph.

 

[RRitt]

Re: 1999 force 120 hp

"rough seas ... flat seas"

as in ocean? is this an ocean boat left in water? is your hull clean? barnacles and seaworms would make about the amount of performance loss you seem to have.

 

[fcross69]

Re: 1999 force 120 hp

I would re prop it if you cant run the rpm's you want for the load you carry your just laboring the motor. I would want to able to atleast hit 5200 at WOT I found that once I proped my boat to my normal use and keeping able to run in my operating rpm range it worked alot better for me. I used the prop chart on maxrules to figure weight, length, motor size, to prop size.

 

[roscoe]

Re: 1999 force 120 hp

"rough seas ... flat seas"

as in ocean? is this an ocean boat left in water? is your hull clean? barnacles and seaworms would make about the amount of performance loss you seem to have.

He's in Wisconsin, on Lake Michigan.


West winds, flat water.
South, east, or northeast winds, turbo blender.

 

[RRitt]

Re: 1999 force 120 hp

He's in Wisconsin, on Lake Michigan.


West winds, flat water.
South, east, or northeast winds, turbo blender.

LOL. this time of year, about 25% of Cape Coral is from either Wisconsin, Michigan, or Ontario.
well, so much for the barnacle idea ...
It strikes me that a factory prop with a healthy engine and a healthy hull should still do factory speed.

 

[PETE BUTZEN]

Re: 1999 force 120 hp

Thanks for input . I just baught a 13.5 /17 . alm , on ebay , it was only $ 34 bucks I will try that and if that works I can go to stainless . I talked to Frankie G and he recomended a eneritia prop ? Any advice on that ? Pete .

 

[jerryjerry05]

Re: 1999 force 120 hp

My opinion on stainless=NO!!!! It's a lot tougher than aluminum and it can also lead to shaft damage if hit just right.
It would be ok if you can guarantee your never gonna accidently go in shallow water and hit the bottom.
Aluminum gives out easier than stainless and is way cheaper and easier to fix. If you decide the 17 alum is ok then change to stainless get a 15P .
I think the Eneritia is for higher HP motors starting at 135??

 

[PETE BUTZEN]

Re: 1999 force 120 hp

Why do you say 17 al 15 stainless ? Pete

 

[PETE BUTZEN]

Re: 1999 force 120 hp

Hey Jerry ! I was wondering why you said 17 p alm / 15 p stnls . Thanks Pete

 

[jerryjerry05]

Re: 1999 force 120 hp

The alum will turn faaster because of weight.
It's a lot lighter.
The SS will lower rpm's about 300=400
So if you want to run a 17A and it runs 5500.The same 17S will run at 51-5200
So dropping down to a 15S will bring up the rpm's to where they belong.