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We have purchased 3 used boats in the last 4 years. (Kept 2) The first one was owned by a guy who apparently saw the muscle boats in his area of Long Island and was keeping up with the Jones". He had 28Ps on a Bravo 3 on a 25' Parker. Couldn't get above 4400 rpms. We changed them out for 24s and it was like a new engine. Sold that boat and "upgraded" to a newer 25 Parker. I can't remember what size P is on that Yamaha 225 but the highest rpms we can get is about 4900. Not a big problem because no one here is speed demon but it seems too low. The last boat has a Honda 130 and we can't get that above 4400 rpms. Will rectify that when we pull her in a couple of weeks. Are we the only ones who have this situation or have others found themselves overpropped? Glen Es thread got me thinking about this. Granpa
Naturally from what I wrote, I think so...but it is somewhat understandable...overpropped and "buried" in my opinion...less prone to over rev and blow out..therefore reducing litigation....I would probably do the same thing if I was a mfr....
It's not up to the manufacturer to prop a boat. It's the dealers responsibility to be sure the boat is propped right for the customer. We do all of our rigging here, but if I got a boat in from the mfr. that wasn't propped right I'd send the prop back and tell them to send me the right one.
But..... but....... but if it's the manufacturers that are "over" propping the engine/boat combo and thereby reducing the ability to run in the preferred RPM range, aren't they creating more problems for themselves in warranty issues????? As we all know an engine that is "lugged" will live a shorter life and have more problems than one which can reach the designed RPM's and "breathe" easier........ I'm soooooo confused.......
Yes - I have never purchased a boat with the correct prop. I always have to drop a size to get the engine in the correct rpm range with real conditions.
My experience from the boat I bought (used, 21' CC, 2200 lbs dry weight,150 HP opti) is,YES, grossly overpropped. had a 21" pitch laser II.engine hit max 4900 RPM ( rated for 5700 max @ WOT) and had a lot of carbon buildup.i propped down immediately, first to 19" P mirage and then further to 17" p mirage,as i am doing a lot of offshore fishing and my boat handles more like a Zodiac than one of your regulators or Fountain. I can now keep it on plan at as low as 2400 rpm, fully loaded, doing 13 to 15 knots against the sea 9 which is what i need most of the time).
Down here they sell bpoats to a largely uninitiated public that goes out almost exclusively in the bay and they tout top speed over everything else. If one has not been in the open ocean it is hard to understand the beauty of planing at low speed low RPM and going anywhere in most weather situations
I guess diff mfr's do diff things - both wellcraft and fountain send the props with the boat....I don't think they prop them to be completey overpopped, they just make sure they are in the complete low side of the WOT op range, IMO....
and bailey - the propblem created by overpropping is a very long term one, one that occurs way out of warranty, IMO, so it does not impact warr expenditures....
and let's not call this a major marine industry conspiricy, just one that that mfr's don't give much thought to the optimum setup.....
Let's do a test. Everyone go to the Merc website prop calculator and have it select the prop for your particular boat/motor configuraion. I bet in almost all cases the prop selected by the Merc calculator will be larger than what we finally have installed on our boats. Report back with your findings.
In my case they prop calculator says I need to use a 19 inch pitch and this is what the motor came with. I changed over to a 17 inch pitch prop and it is like night and day. I get better hole shot, low end plane speed and even better top end speed.
Since the boat operator can control his top end RPM (come back on the throttle) and since new boats do nothing but gain weight with time, it would seem the manufacturers would select a prop on the small side if anything. My belief is they go the wrong way.
All of the charts that I used to calculate appropriate the SS prop for my boat recommended a 19 pitch. Purchased a 17 and glad I did. RPM's with a light load are at very top of range.
__________________ Tom Pass
Sea Blues II
'03 Key West 23WA
Honda 225
Little River, SC/Hamilton, NJ
Proud Parent of a Marine
Sailfish is overpropping the 2360 with F115's at current but that may change soon. The 2360 needs 16" or smaller to be in the right RPM's. I have a set of the 16's for sale. It comes with 18's and you wont see over 5500 with them.
Almost all used boats I looked at used and my last new Hydrasport/wRudes were over propped. They told me it was for fuel economy. Don't buy that - it leads to the early demise of the motors. Read the manual and make sure you are in the max rpm range at full throttle.
__________________ 1st Cav Div Air Assault Infantry RVN
-Can Do........ and .......Carry On -
Another thing I think may be part of the problem, is they prop the boat out with 3 gallons of gas, no t-top, and no gear.
They hire a "little person" to drive it for the test, and have him wearing bikers spandex.
He's not allowed to eat for 3 days before testing. I met him at a bar once. His name is Bob.
Then they can say it performed great and hit X speed !!
ken2 said...
They hire a "little person" to drive it for the test, and have him wearing bikers spandex.
He's not allowed to eat for 3 days before testing. I met him at a bar once. His name is Bob.
I am now officially creeped out...
__________________ .
Capt. Kevin ~~~~~~~~~~><((((*>
Are most boats sold "over propped" 
1st Cav Div Air Assault Infantry RVN
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