Just checking what props people are running and how to check the pitch of the ones I currently have. I have purchased the 268 with the new twin F225's. How do I check what props I have (is it written on them somewhere?) & I also think I am not getting full revs at the moment?
What props should I be running
- Thread starter Absolute
- Start date
You may have to pull the props to look for the marking, as it is usually stamped on the bottom of the hub section.
I assume that you have Yamaha props and, if stainless steel, they are probably the original Saltwater Series props. These are 15.25" in diameter, come in 2-inch pitch increments, and are really very good overall props. My best shot would be either 17" or 19" pitch for those props on that boat.
When propped properly, you should be able to hit the top of the WOT RPM range with the boat loaded on the light side, and the engines trimmed up but not ventilating. Being able to hit the max RPM under this loading condition ensures that you should still be in the (preferred) upper half of the RPM range when more heavily loaded.
The specified RPM range for the F225 is 5000-6000, so you should be close to 6000RPM when lightly loaded. If not, then you are overpropped, which is not good for the long-term health of the engines and not as good for "bite" in rough sea conditions.
So, take a look at the props and let us know.
Brian
I assume that you have Yamaha props and, if stainless steel, they are probably the original Saltwater Series props. These are 15.25" in diameter, come in 2-inch pitch increments, and are really very good overall props. My best shot would be either 17" or 19" pitch for those props on that boat.
When propped properly, you should be able to hit the top of the WOT RPM range with the boat loaded on the light side, and the engines trimmed up but not ventilating. Being able to hit the max RPM under this loading condition ensures that you should still be in the (preferred) upper half of the RPM range when more heavily loaded.
The specified RPM range for the F225 is 5000-6000, so you should be close to 6000RPM when lightly loaded. If not, then you are overpropped, which is not good for the long-term health of the engines and not as good for "bite" in rough sea conditions.
So, take a look at the props and let us know.
Brian
Take a look at this link. It is the 270, but pretty close.
http://www.yamaha-motor.com/assets/...in_otb_4StrokePerf_HPV6_225hp_02-55-GRW-B.pdf
http://www.yamaha-motor.com/assets/...in_otb_4StrokePerf_HPV6_225hp_02-55-GRW-B.pdf
Absolute,Absolute said:
As you go through your trial and error with props just remember if you want to raise the RPMs , lower the pitch and visa versa. That's assuming you don't change the diameter of the prop.
If they are Yamaha props, they should be marked on the hub, behind the prop blades, likely they are 17M props unless they ahve bee changed. If you are looking to go to another prop, there are some companies that will let you try props at low down payments and you pay in full when you find the right prop size and pitch, you only lose your down payment if you damage a prop, Mercury has this plan now as well from the factory, and they have some good props, some guys in my marina have had great results with merc props on Yamaha engines.
Thanks guys for the help so far, I will check the numbers on the props and also see what revs/speed the boat is doing and get back to you
Make sure you check rpm and speed with a full load of fuel, if you do not the boat will never have power to plane out when loaded, you want to be close to full rpm with a full load, that way with 1/2 fuel you are turning max rpm, but when fully loaded you have the power to get on plane rather then fall flat on your face. It is likely the props you have now are good, they may not be the absolute best match but typically they are good if a Yamaha dealer put them on, they will not release the boat unless the engines spin within specs. You want to spin up to the top portion of the max range, if you are in the lower portion you may want to change the prop. also rememeber, you may spend $400 a prop, if you are looking for fuel savings, how long will it take to repay them, it may not be worth it for that reason, but is well worth it if the engines are working too hard to turn the props and get the boat to speed.
Thanks for the info guys, I just called the local Yamaha dealer and they said the prop size will be in between the blades on the stainless ones. They also said that each prop will be $1000 for one and nearly $1500 for the counter rotating one (wouldn't want to be changing these too often). Anyway they also said they may have a Yamaha exchange program if required. Will do some tests and get back to you all.
Holy smokes, $1000? What is that exchange rate? I would skip Yamaha SWS props and get Merc/Quicksilver Mirage+, probably 19". They are much better props, and can be found on ebay for $275 or so new.
plymouthgrady
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prop
Yeah, $1000 seems pretty steep. I run a Michigan 'Ballistic' on my 250
SWS II. I cost less than $500, weighs less than the Yami fact. (which I carry as a back-up) and gained about 4 mph.[/img]
Yeah, $1000 seems pretty steep. I run a Michigan 'Ballistic' on my 250
SWS II. I cost less than $500, weighs less than the Yami fact. (which I carry as a back-up) and gained about 4 mph.[/img]
I just checked the props and they say 21M which I guess is 21 inch. I have 3/4 fuel and bascially no other weight in fishing gear and on ly 1 person on board. Max revs were 5200 and 42 miles per hour which I beleieve with twin F225 Yamahas is both down on revs and top speed. I am sure with 3-4 on board I am below 5000 revs.
Absolute said:
WOW, too much pitch by far.
Rule of thumb is that a 2" change in pitch will give a 300-400RPM change.
I would strongly suggest a pair of Yamaha Saltwater Series SS props, in 15.25" diameter and 17" pitch.
That should put you where you need to be on RPM, you will have better "bite" and your top speed will likely be the same, due to the higher RPM.
There are, of course, other options with props from other manufacturers, but the bottom line is that you are badly overpropped and need to reduce pitch significantly to get the RPM up close to 6000.
As to the cost of getting those on your side of the world...
Brian
Thanks Brian for your help, I will make some inquiries about 17 & 19 inch props today. It would be great to be able to test a couple of options?