is a 26" too much?

[panopix]

I plan on replacing my prop. I believe the present is a 21pitch prop,would a 26" be too much for the engine? its a 120hp force 1995 on a quantum fs180. RPM is supposed to be between 5000-5500, tach not working. Boat is around 1300lb. Any suggestions as I like to go fast

 

[Bondo]

Re: is a 26" too much?

I plan on replacing my prop. I believe the present is a 21pitch prop,would a 26" be too much for the engine? its a 120hp force 1995 on a quantum fs180. RPM is supposed to be between 5000-5500, tach not working. Boat is around 1300lb. Any suggestions as I like to go fast

Ayuh,... I would think so,...
But, without knowin' yer rpms, Who's ta say..

 

[Faztbullet]

Re: is a 26" too much?

It might turn a 26" pitch with a 75hp shot of nitrous

 

[steelespike]

Re: is a 26" too much?

My info indicate the FS180 is 1750lbs a 26 is very likely way too much prop.
In fact the 21 could be a little much as well. I would suggest getting the tach working,
do some test runs get us the wot rpm and gps speed if possible.

 

[Texasmark]

Re: is a 26" too much?

I plan on replacing my prop. I believe the present is a 21pitch prop,would a 26" be too much for the engine? its a 120hp force 1995 on a quantum fs180. RPM is supposed to be between 5000-5500, tach not working. Boat is around 1300lb. Any suggestions as I like to go fast

Yours is probably 2:1 gearbox. Even with a 2.3 gearbox, a 21 on that boat would be in question. You are looking at more like a 17-19 depending upon whether or not you want to use water toys. The more the toys and the harder they pull the more you want to drop below the 19. Rpm check will verify what I said but I am there, you can take it to the bank. BTDT

Mark

 

[Silvertip]

Re: is a 26" too much?

A non-working tach is the single most important "missing" piece of information we need to help you. What the engine specification IS for WOT RPM is very different than what it actually DOES. The difference between these two numbers is what tells you what prop you need.

 

[Frank Acampora]

Re: is a 26" too much?

There was never a 120 Force made that was capable of swinging a 26 inch pitch prop on anything bigger than a 12 foot racing hull.
Like mark said: 17 to 19 would be more like it.21 might work but would probably be a stretch.


As stated numerous times above: First get the tach working, then go from there.



Here is a 700 pound 14 foot hull with a Force 125 on it. It swings a 21 pitch prop. Granted, it is the older US Marine version, not the Mercury lower unit like you have but the comparison is still valid.

You can not "think" the current prop is a 21 pitch You must know. Find the numbers on the prop or compare to a known pitch prop. Can't get where you are going without knowing where you are now.

 

[panopix]

Re: is a 26" too much?

The reason I think it a 21" is because the original owner said it was the original prop and the owners manual said it was fitted with a 21". I'm working on the tach, and I'm waiting for my prop wrench to arrive. I'll update you then. Thank for the input everybody.

 

[steelespike]

Re: is a 26" too much?

The motor may have been shipped with a 21 but the final prop would depend on what boat the motor was instyallewd on.
If itb was your 1750 lb boat its lighly unlikely to be a 21.

 

[panopix]

Re: is a 26" too much?

So I finally got the tach working and prop off. As I suspected it is a 21" prop. I replaced with a SS 21" and it runs much more smoothly. RPM's are around 5350 at WOT. I get around 48mph on the oem speedo but ill need to verify with garmin once instslled.Thanks for the help, its been much appreciated!