Engines,props, and wide open throttle

[DuroBoat]

I’ve just been able to open up to max rpm on my new engine - 300 Yamaha on a SeaSport 22. I was able to get to 5300rpm with two people and a couple hundred pounds of halibut gear. I think I should be closer to 5500 but I was skipping along at 43 knots which was faster than I’ll ever need to go. Hole shot is great and fuel burn surprisingly good; approx 55 gals to run from esquimalt to Nanaimo and back again with 4 people and a lot of gear. Better economy than the 5.7inboard. At 3800rpm, I’m just shy of 30knots. The max rpm may not be ideal but the overall performance is so good, I can’t be bothered with playing the prop game. I’m assuming having a lot of hp ensures the engine is not working too hard and cruise rpm is a bit lower, providing better fuel economy

 

[wolf]

I’ve just been able to open up to max rpm on my new engine - 300 Yamaha on a SeaSport 22. I was able to get to 5300rpm with two people and a couple hundred pounds of halibut gear. I think I should be closer to 5500 but I was skipping along at 43 knots which was faster than I’ll ever need to go. Hole shot is great and fuel burn surprisingly good; approx 55 gals to run from esquimalt to Nanaimo and back again with 4 people and a lot of gear. Better economy than the 5.7inboard. At 3800rpm, I’m just shy of 30knots. The max rpm may not be ideal but the overall performance is so good, I can’t be bothered with playing the prop game. I’m assuming having a lot of hp ensures the engine is not working too hard and cruise rpm is a bit lower, providing better fuel economy

Your pitched to high you need to go down more YES you have to play the pitch game .. you have to ensure your engine is performing where its supposed to be in the range, your dealer will help you out .IM MORE then sure if you gave the numbers to the dealer he will say try this prop . ASK what the manufactures range is . trust me if you do not follow what they say and the engine prematurely blows and they see you didnt reach the max RPM they may void any warranty.
when your engine runes at optimum rage you actually get better fuel economy. the speed will drop down with a lower pitch and a higher RPM...

 

[Fisher_dude]

I messed around with my boat for awhile after I got it. 3 different props later and had to lift my motor to the top hole. I gained 2mph at 5000rpm by moving it up 1 hole. Top speed doesn’t change though. Manufacturers spec is 5800-6400 WOT on my 300 Verado. Fuel burn at 6200 rpm is horrible. That supercharger sure sucks it back. I cruise at 4800-5000rpm doin 28-30mph with a full boat burning around 14gph. Might take you a bit of messing around to figure it out but once you do, it’ll be worth it.

 

[Sharphooks]

I’m all in with Wolf on this one. You’re pitched too high. You’re getting that type of speed at modest RPM’s because you have a 300 HP outboard on a 22 foot (relatively light) boat. See if you can borrow a prop that’s pitched 2” lower then the prop you’re running now. You’ll be able to get the same speed at 5,500 - 5,700....Your Yamaha will thank you for it.

 

[BC Coast Pilot]

Unfortunately after SG forgot to install my shifter cable leaving me floating away from a dock without propulsion, installed my kicker steering backwards, corrected the kicker but then installed my main steering backwards (not kidding), then corrected the main but put the kicker backwards again, and finally telling me they don’t know how to reinstall my dash switches (all after having my boat for 4 months when they promised 1 week), I cannot go back and get them to correctly prop the engine. I’m taking my boat to Sherwood need week to have them fix my dash and kicker steering. Btw, everyone of these issues came after I was told by SG the boat is all ready to go, towed and launched it before realizing all these screw-ups and had to tow my boat back to SG each time. It turned in to absolute hell. I’m still upset and now may have to buy a new prop?

What are you running for a prop now?

 

[DuroBoat]

What are you running for a prop now?

Thanks for the input guys. The prop I’m running now is attached. The Yamaha website says max wot is 5000 - 6000 for my model.. if I’m hitting 5300, maybe 5400, shouldn’t that be ok? Feels like it’s screaming compared to the 5.7 inboard it replaced!

 

[noluck]

that prop is fine, you have alot of hp to get you on plane even loaded heavy

 

[BC Coast Pilot]

Thanks for the input guys. The prop I’m running now is attached. The Yamaha website says max wot is 5000 - 6000 for my model.. if I’m hitting 5300, maybe 5400, shouldn’t that be ok? Feels like it’s screaming compared to the 5.7 inboard it replaced!

Sounds pretty good, my prop tech used to say trim the $hit out of it at WOT without losing traction and see what ya get.

 

[Squire]

I have the same outboard on a Campion682 which has a dry weight around 600 lbs less than your boat. The prop you have is a good prop but you should have it in 17P. My boat with that prop in 17P hits 5800 rpm and handles great. If you go down to the 17P you will immediately notice how much less your outboard works to get up on plane and to maintain cruise speed.

Edit: Response was to Duroboat with his 22’ Seasport, not the OP

 

[Aquaholic]

Sounds pretty good, my prop tech used to say trim the $hit out of it at WOT without losing traction and see what ya get.

I used to trim it until it sounded like open headers. There's your maximum rpm's.

 

[BC Coast Pilot]

I messed around with my boat for awhile after I got it. 3 different props later and had to lift my motor to the top hole. I gained 2mph at 5000rpm by moving it up 1 hole. Top speed doesn’t change though. Manufacturers spec is 5800-6400 WOT on my 300 Verado. Fuel burn at 6200 rpm is horrible. That supercharger sure sucks it back. I cruise at 4800-5000rpm doin 28-30mph with a full boat burning around 14gph. Might take you a bit of messing around to figure it out but once you do, it’ll be worth it.

I had a similar issue with my 300 verados. Not a height thing but I switched from mirage plus to the ECO Enertia which has a larger dia at 16inch and improved economy by 25%. Those props were designed by merc to address the high burn rates of the Verado, keeping the revs under 4000 keeps me out of the supercharger so I cruise at 37/3800 burning 35 litres an hour (9gph) per side at 23 knots. Used to be 95 liters hr combined! I also tried the rev4 which was a close second to the ECO Enertia. If I crank it up its 225 liters per hour

 

[wolf]

It takes about 5 mins to re and re a prop really not hard , Think of it this way going up malahat in 5th gear its doing it but its kinda pinging and sower response .going up malahat in 4th gear zipping up the hill no problem. You really dont want to lug these engines. with price of fuel etc you want to optimize your package , Ask the dealer he will help you out after you do your first 20 hours and time for a oil change write down all your numbers etc WOT and speed fuel burn,full fuel tank, half full tank speed etc on every outing .
then ask for a 17 and re test a few times im sure you will see a difference.

 

[DuroBoat]

It takes about 5 mins to re and re a prop really not hard , Think of it this way going up malahat in 5th gear its doing it but its kinda pinging and sower response .going up malahat in 4th gear zipping up the hill no problem. You really dont want to lug these engines. with price of fuel etc you want to optimize your package , Ask the dealer he will help you out after you do your first 20 hours and time for a oil change write down all your numbers etc WOT and speed fuel burn,full fuel tank, half full tank speed etc on every outing .
then ask for a 17 and re test a few times im sure you will see a difference.

Unfortunately I had such a terrible experience with SG power, I cannot go back there and I’m stuck with this prop unless I want to buy a new one.. I’m sure you’re right tho Wolf.

 

[Rain City]

Unfortunately I had such a terrible experience with SG power, I cannot go back there (after spending $45k for a new engine and waiting 4 months for them to properly install it with so many issues) I’m stuck with this prop unless I want to buy a new one.. I’m sure you’re right tho Wolf.

If you don't currently have a spare prop, it wouldn't be the end of the world to buy a second one. Some guys purposely have two different props. One for fuel savings and longer trips and another for fully loaded outings or pulling skiers and all that. It would be good practice for you to learn how to change your prop anyways.

 

[Squire]

You should take the prop and thrust washer off every year and regrease the shaft and splines anyway if you don’t want your prop choice to be permanent.
Online marketplaces are a great way to buy and sell lightly used props. I’ve acquired half a dozen this way and after my experiments I got my original investment back. Check out the inventory at boat shops in your area and you just might get lucky as well.

 

[SpringVelocity]

Unfortunately I had such a terrible experience with SG power, I cannot go back there and I’m stuck with this prop unless I want to buy a new one.. I’m sure you’re right tho Wolf.

You really should learn to do this yourself and keep spare props on that boat.

 

[wolf]

You should take the prop and thrust washer off every year and regrease the shaft and splines

Yes its a special "spine grease" blue in color

Unfortunately I had such a terrible experience with SG power, I cannot go back there and I’m stuck with this prop unless I want to buy a new one.

Phone Sherwood and ask for jo ann and tell her the scenario of whats happened they may be able to help you.

 

[DuroBoat]

Thanks wolf - already spoken to Jo and I’m booked to take the boat to Sherwood tomorrow to get her all fixed up

Yes its a special "spine grease" blue in color

Phone Sherwood and ask for jo ann and tell her the scenario of whats happened they may be able to help you.