1999 Promax 300???
#1
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Joined: Apr 2001
Posts: 2,982
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From: East Coast
Guys , I need your help. I have found a 1999 Promax 300 with around 200 hours on it. It appears to be in great condition. It also has a sportmaster gear case. Any gripes of this model year? Thanks for the help.
#3
Never heard anything bad about the 99's I do know the x's put out alittle more power, Mercury did do some port work and exhaust work on the new ones, but if the price is right, go for it!
#5
The 300X and the 300 older Pro max have completely different powerheads. THe X is based on the Optimax 3 liter powerhead and has approximately 10% more power. The Promax is based on the older 3 liter block and runs almost 1000 RPM lower.
The good news.....the Promax lives longer (not so highly stressed) and behaves like a kitten around docks etc.
But, what do I know?........I'm obsolete.
T2x
The good news.....the Promax lives longer (not so highly stressed) and behaves like a kitten around docks etc.
But, what do I know?........I'm obsolete.
T2x
#6
I have a 99 PM 300. Bought it with 35 hours on it. You can verify the hours if you get your hands on the computer to plug it into.
Mine has been great so far. Supposedly they only make about 290 hp at the prop and the 300X makes around 335hp. I understand they are good for approx 150 wide open throttle hours. They are much quieter than 2.5s which is nice for back seat passengers, and they are fairly low maintenance.
Mine has been great so far. Supposedly they only make about 290 hp at the prop and the 300X makes around 335hp. I understand they are good for approx 150 wide open throttle hours. They are much quieter than 2.5s which is nice for back seat passengers, and they are fairly low maintenance.
#7
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I have a 1999 Pro Max 300 and have been real pleased with the performance and reliability of this motor. I had a stator go out at about 10 hrs and that has been it. I had a dyno check done on mine 2 years ago, it showed 303 Hp at 6200 Rpms. I saw a 300x on the dyno at Mercury Racing producing 330 hp at 6800 rpms. They are reliable motors.
#8
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Joined: Aug 2008
Posts: 1
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From: Chico, Ca.
I have been running a 300 PM that I bought used with 30 hours on it. I've been running it on a 1985 Shadow very hard for the last 8 years putting an average of 50 hours a year on it. I have not had one problem. But I would like to have the extra 30 ponies of the 300X.


