Prop Testing - Disappointing!
 

In an effort to find something to replace my cracked 24 Hydro, I spent yesterday afternoon trying the few left-hand props my marina had around. Air temp was in the low 80's, with water probably about the same. There was some wind (maybe 15 mph) and a light chop. Clear Lake ranges from fresh at one end to almost salt at the other. The two numbers I recorded are basically with and against the wind. Trim ranged from a little less than 5 to 6.8, depending on the prop, tabs all the way up. These are very rough numbers, since I was driving and trying to read the GPS at the same time.
The boat is a 1996 29 Fever with carbed HP500 and I'm guessing a bit more than half a tank of fuel.

24 Hydromotive (4 blade)
with wind: 67.1 @ 5000
against wind: 64.7 @ 4900
(Note: My 24 gave me 5200 at WOT before it cracked.)

24 Bravo I (4 Blade)
with: 66.7 @ 5300
against: 64.6 @ 5300
(I couldn't even trim all the out, the rpms were running so high.)

Planing for both of these props, was about the same and quite good.

25 Mirage Plus (3 blade) - My mechanic's idea - bad!
with: 64.6 @ 4900
against: 62.0 @ 4900
(Planing was terrible, almost couldn't get her up.)

27 Hydromotive (4 blade)
with: 65.0 @ 4850
against: 62.6 @ 4850
(This seemed strange. The rpms are where I'd expect, but the speed should've gone up. Planing was a bit more difficult than with the 24's, but something I'd just have to get the feel of, not nearly as bad as the 3-blade.)

The handling was great with all of the props, no chinewalking or feeling like I'd spin out in the turns.

I'm still undecided as to what I want to put on her. Suggestions are welcome.

I was reading a thread yesterday I think in the Q/A section about HP500 carb valvsprings going soft and should be replaced after 200 hrs.....Maybe if you changed them you could gain some rpm or allow you to prop up and find that speed...........Doug

Q/A-'' Valvesprings" by "2 air"...........Doug

strange why you're getting around double the slip % (21) with the 27" v 11% with the 24" hydro. Probably trimming higher with the 27" in an effort to get the RPM higher.

BTW, hydro can fit diffuser rings to help planing by inducing slippage initially to get the turns up. The top end is sacrificed a little though.

I figure my driving is still somewhat of a variable in this. I couldn't keep track of exactly what I was trimming to and watch the GPS, tach and water ahead. I do recall trying a few different settings with the 27 though, because I was surprised it was slower. If it was a repitched 26 like my mechanic said it was, it may not have been done right.
With regard to the valve springs, it could be a problem, but this engine only just hit 150 hours and was recently tuned up. My mechanic didn't report anything amiss.
Oh yeah, one thing I didn't put with the first post: The factory test sheet said 70 @ 5050 with a 26 Hydro, cold day, 30 gallons of fuel and Reggie driving. Maybe she never was as fast as what the rest of you guys have...

Jana,
My first report said 72@6000 with Reggie driving. :eek: I guess they don't believe in proof reading.

I'd give the Bravo 1 another try. You probably will need a 26p with the tips cut down to make it the equivalent of a 25. Try a stock 26 and see what your numbers are. Have your prop guy call Merc and get the templates to trim the blades. With this method the cup stays the same and you still have a larger prop to go back to if you do minor engine work.

Dan

Mike,
What customer service? :mad: I asked if Merc was having a water pressure problem on my year engines, answer NO! Is 40 lbs. of pressure ok? That was answered with a question. Does your engine overheat? NO! Do you have water in your oil? NO! Then sir you don't have a problem. I asked why I have gone through 5 circulating pumps? Answer was I don't know but your engines are out of warranty.

My response is to file a complaint with Boat US. I believe Merc may have a water pressure issue on some of their engines.
I guess custom power might be the way to go in the future.

Dan

Candyman - Which way was that test report off? I assume you were faster. The guy I bought the boat from said he saw 73 on the speedo before he decided to put a nose cone on. That says that I should get 70 on the GPS.
The only reason I didn't try more Bravo I's is because the 24 was all we had at the marina. I'm in a bind because I have to have SOMETHING on the boat before June 8 so I can go on a Poker Run out here.

Jana,

Just my observation, but it seems like you are not getting the RPMs high enough. Even with your Hydro 24, 5200 at WOT should be faster than 67mph, I actually ran 5350 rpm WOT with 26 Hydro speedo at 79mph,(wich means 74-75mph) yesturday. Just a thought do you carry allot of stuff on the boat, anchor,tool box, water tank full?, # batteries, excess water in boat?

Also another idea, and I would call fountain on this, you say its a 1996, maybe the X dim is higher on the newer ones??

Just trying to give you some other direction to look,

Good Luck

Will;)

Janna,
My rev limiters are set at 5050. I have baby motors, 454 Mags. If you call the factory ask for Marty Bosinger. He is the man that does the rigging and is the only one I have talked to lately that still cares over at Fountain:(

Dan

Candyman,

You're right about Marty.

Mark S.

FeverMike - Check your e-mail. I sent you the right phone numbers. What pitch was that Hydro you gave the speeds for?

Jana, quick check, remove the flame arrestor and with full throttle applied make sure your throttle plates in the carb are at a 90 degree angle to the carb base plate. Just a thought.


Jan

FeverMike,

Where are you getting the Hydro labbed?

Thanks,

Mark S.

Fever Mike,
What exactly does it mean to have a prop labbed?
Lefty

jana, I have a 1990 29ft fountain and my father in law has a 1998 27 fountain with a hp500 spinning a 25p hydromotive at 5200rpm at 73gps mph. I would think your boat could turn a 25

That's what I'm thinking too. Definitely going to try the 25. 26 also and a couple of Bravo I's. Maybe Spinelli too, if I can get one. After the Poker Run next weekend, prop testing will get back in gear.

Jana
I'm sure if you ask Chuck, he would be happy to help you hold the GPS and watch the rpms or watch the water ahead for you. That is if he can keep from chuckling about your efforts to beat his "new" Powerquest "family boat".:D :D Just joking...really....we used to own the old PQ and have heard how happy he has been with it . He mentioned that you went out with him and did the GPS on it. He just e-mailed us with his latest escapade on the way to Clear Lake:eek:

Anyway...hope you get your prop problem worked out before this weekend. Sounds like a great poker run. Have fun;)

Tbikini

Yes, I did the GPS thing for Chuck. 72.1 mph (4 people and a full tank)! But of course, your old boat has twins. I've actually got a mounting bracket for the GPS on my boat, so I'd rather run without the extra weight ;) . He had an "interesting" day to say the least yesterday, but it all worked out OK. I've borrowed a prop from my marina for the run and will get back to a more leisurely prop test schedule after it's over. I'll have a chat with Reggie at the next race I go to and tell him how I got smoked by a "family" performance boat. Ought to get a reaction!

Jana, I live near spinelli and have had Mike build me props and he does a good jod. but I have not been there in a year and read in one of the power boat mags that he had sold out or was going to sell. There is alot of his props out there and they work well. good luck I have been testing to night and found that 28p hydrs and having the props turn in make my fountain feel like a brand new boat I had them turning out and was going to sell them. My friend said put yuor props in the other drive and run the boat in rev. I thought he was nuts, but we tryed it and you can not believe the difference. 84mph on gps at 5200.

Way to go! Hopefully, I'll have as much success when I finally get to doing this. One of my friends runs Spinellis on his 35 and promised that he'd see about finding me a couple of loaners to compare. In or out makes no nevermind for me since it's a single, but are you suggesting I run a righty instead of the lefty?

Jana, I can't say but our 27 has a righty. I just finished swaping my drives so that my props turn in instead of out and what a difference it made on my 29ft. I must go put it back in the lift.

check the fountain webpage. it has been re-designed and has prop info.

Jana,
First off what kind of water are testing in ? Freshwater, saltwater,or brackish?
Reggie tests the boats in brackish water in a river which I'm sure has current, so I'm assuming he does a few runs and then writes down the average.
For some reason Fountains love Hydromotive props. probably because the lift of a Hydro will carry the whole boat. I would stick with a Hydro.
Also what was the humidity like ? The type of air your in is real important, if it is humid the motor is going to be way down on power.
Just bringing up some other variables.

Dredge - thanks for the heads-up. I hadn't been on the Fountain site in a while. I'll see what I can dig up later.
26Scarab - I'm in Houston, so it's hot, humid, warm water - salt in the bay to a bit brackish if I'm in the lake. I'm griping because of the guys in Florida who say they're a good bit faster than me. I'm going to try a few Hydros and Bravos, just to see what works. BTW - the 70 that was on the test sheet was in the middle of winter with a lot less fuel than I usually carry. Maybe she really is just a high 60's boat.

prop info
 

Here's the link to the prop info on fountain's website.
http://www.fountainpowerboats.com/Te..._sportboat.htm

dockmech...How are things going? By the way, I thought your props were 29's?

Thats interesting, Fountain is saying on 27 w/ 500efi, put a 26 Bravo, My boat is a 2001 w/ 500efi and reggie did prop testing on my boat and went with 26 Hydro????? Guess he is back to all merc stuff??

WILL:cool: