Stainless Props

[capttom1]

Has anyone ever installed a set of stainless props on a 25CC. Right now I have B-5’ aluminum props and I’m thinking of installing C-4 stainless?
Capttom1 (TomT)

[Hey Doc]

Props

Never done it on a 25 cc, but several other boats. If you switch to a stainless prop that lets the engine turn its rated rpm level, you should see a noticable difference in performance. Probably worth the switch, but you may want to consult with Mac first.

[capttom1]

SS props

Hey Doc,
Thanks for the speedy reply. I raised the question because when I was at the NY boat show I spoke to a Volvo rep about my lack of speed. His answer was to first perform a compression test and then to install stainless props a size smaller then the B-5’s. The boat is a 1996 and I’m (me and the boat) carrying a bit more weight now. My top speed (beginning of the season) is 30K at an rpm of 3400. I need new props and I have pretty much decided to search the web for SS units.
Thanks Capttom1

[Hey Doc]

Prop size

Just make sure that the prop size on your new stainless propellers is correct. It is likely that they will have to be smaller than your current aluminum props, but if you can run the full range of your rated engine rpm's you should be in good shape.

[CJO]

SS Props

Capt Tom
I changed the props on my 25. It had B-6's and I went to C-5's thinking it would give me more rpm. My rpm stayed the same should have probably dropped one more size.Got tired of having the aluminum props fixed from cavitation burn, since going to the stainless I have not had that problem.

[Bite Me]

i had a 25 before my 2006 28. also couldn't get max rpm from the alum. B-5's.
took them to a prop guy and told him how many more rpm's i wanted and he changed the pitch. they ran fine. saved a ton of bucks.

[Little Dandy]

I run C-5's on my boat.

[Hot Rod]

I just replaced B-5's and installed C-4's on my 98' CC25'. I couldn,t be happier. Rpm's went up from 4000 to 4450. The boat runs better than I expected. Comes out the hole strong and smooth. Best money I ever spent. By the way I did talk with Keith ( Mac's son) be for I made the change. He advised me that B-5's should be used on the 25. I guess boats are different even if they are made the same. I have a new 454 bored out to 465 cu. ins. with 375 HP. at 4500 RPM'S on the dino.My cruise @3400 rpm's is 31 mph. Haven't burned out the first tank of gas, yet so I don't know what the fuel usage is, but I'll let you know. The engins doesn't work as hard with the smaller props and operation is in the middle of the power curve, my mechanic feel the mpg. should go up.

[capttom1]

SS Props

Thanks Hot Rod, Little Dandy, Bite Me and CJO for the great information. I can’t wait for mid March to pre the boat for next season. Hot Rod I installed a Flo-Scan gas meter unit the second year I had the boat. Saved a bunch of money by watching the GPH flow. Now I jump out of the hole and once on plane pull it back to around 3000prm’s and burn around 14GPH.
Thanks again guys. What a great site.
Tom T – capttom1

[NJfishing]

Cavication Burn

I'm having the same issue mentioned above. Seems like every year I have to buy new props on my cc 25 (1999 VP 8.1) due to cavication burn..I'm thinking of switching over to stainless to avoid this but I keep my boat in the water from April - November in a marina and I have heard horror stories about the stainless props causing electrolysis on the drive.... I'm thinking the props being aluminum act like and extra zinc and the props get eatin instead of the drive.

Any comments or suggestions?

[Hot Rod]

I'm a Jersey boy from way back myself, so if you want to spend a little time I'll tell you how to almost eliminate CAVICATION BURN. I bought my 98' 25 two years ago. B-5 Props burned baddly. I didn't think that this is the way Volvo would desige the system. Started to look at other 25's in several other marina dry skacks. Some burned worst some not so bad. probably had to do with usage. Bougth a new set of B-5's, ran out to the inlet and back, 12 miles total. The new props were really burned bad. Called Volvo- no help from their tec. I talked to several other guys ( Keith Privot included ) about the situation and we started to change the orientation of one prop to the next. We found when the verticle blade of the front prop is at 12 o'clock the rear prop has to have a blade at 10 o'clock. With that set up I ran the B-5's for about 150 hrs. with next to no burn. Move the rear prop one spline at a time until you get it rigth. ( As I mentioned before I'm now running C-4's with a bigger engine and couldn't be happier ).
Good luck,
Hot Rod

[JohnD]

SS props

Have SS props on my 95 25CC. As I am 3rd owner believe these were factory install. WOT with one person, 2/3 fuel breaks 40 MPH, about 4400rpm

Have SS on my Honda outboard too. Will not go back to Alum. Just 'feel's like the SS bites better and many fewer trips to prop shop due to coral reefs and sand that ding alum easy and the SS bounces off of.

john

[capttom1]

SS Props

HI Hotrod
I never gave it any thought about the position of the prop blades in relation to each other. I just placed them on and went in the water. Maybe that’s one of the problems with speed and RPM. I’m headed out to the garage to check the props for cavitation burn. Thanks for the info. capttom1

[NJfishing]

Thanks Hot Rod

Thanks Hot Rod - I heard this once from Mac too but I still dont' get it...When you say the front prop is at 12:00 do you mean where the blade meets the hub and if so the front or back since it's on a angle.

I'm going to give it a try but to be honest it makes no sense to me. These props are on the same spline and the opposing blades are going to line up with one and other at some point in the counter rotation. I wonder if it might have something to do with them being lined up with one directly in front of neck of the lower unit which is at 12:00 right?

[Hot Rod]

Made no sence to me either, nor any of the guys at my marina. I had to do something so I kept moving the rear prop one spline at a time until I saw mimimum burn. I tested a ten mile run at a time. that's all it takes to have the burn show up. The back of the front prop is what I refer to the verticel Line ( sorry, I don't have the tec. term ). Try it, I know it works. If you still have any questions, Call I'll be happy to talk to you.
Capt.
EJ
910-289-0512