So now that you have PP, which prop?

[phenom_1819]

With everybody that has installed Perfect Pass lately, and you've tested it out with weight, is the Acme 3-blade still the shizzle?

I dinged my prop today testing PP.  Think it's an OJ 4-blade, 13x13 LH rotation.  Stamped on it is something along the lines of XXXXnson 6 02 (guessing thats the mfg date).  Can't read the first 3-4 letters, but it looks like it may have been an OJ logo.  Now I'm debating whether to repair (what does that cost?) or just pony-up and buy the Acme.   I've already spent WAAAY beyond my comfort this year and the season hasn't even started. SWEET!

[cyclone]

I've had good luck with my OJ 4 blade 13x13 LH .080 cup, probably what you have on there. You need a spare anyway, send it out to get fixed (75$ to 175$) then get a new one. I'm not sure about the Acme, if it was recommended for Vdrives or D drives, search the posts to see. Or, just call Acme and ask them. Probably 350$ for a new one, get a prop kit with the wrench and puller for another 50$. It's worth it in case you need to put your old one back on during a nice day on the lake.

It's only money, you'll make more next week:) Can't put a price on fun!!

[highflyn]

Cal
Unfortunatly I speak from great experince on this one. Your prop will cost you 150 bucks if you take it to Ski Masters.They send the work out but get a better deal then if you or I took it to the same place. They then mark it up to what It would cost us at the prop shop. So I guess it's good to support your local shop. I did a prop exchange with them ( had a few small dings from last year) and then first time out with the new prop managed to kick a rock up at the ramp and put a HUGE ding in it. So im already on prop number 2 and i'v got about three runs in. Good thing my money tree in the back yard is starting to bloom . The mech's at Ski MAsters stayed late that night and installed the new prop with NO labor charge.
Glad to hear your PP is working
Im free next sunday evening to hit the lake. Let me know?
Terry

[blindside]

Yep, got PP and I am still lovin the acme prop!!!

[toyotafreak]

Still don't think we've really heard enough from the guys with ACMEs about how their new prop handles FULL weight runs or what their WOT rpm/mph is, etc. You'd probably be golden with the one ACME's recommending, because you don't do FULL weight runs much, right?

[phenom_1819]

So Ski Masters was cool enough to give me a brand new 4-blade OJ for $125.  You know I couldn't pass that up -- and they knew they'd be getting more business from me soon.  Betcha they didn't think it would be the next day.

I've got a fairly subtle whining/almost-grinding sound coming from my driveshaft and/or transmission.  I really hope it's not the tranny, and don't think it is.  Wonder if it's the prop strut-thingy, or the dripless packing (which I had never really examined before today, it's pretty damn cool).  Most boat owners would never notice the noise, but I know that it's a new noise.

So anyway.  Anybody know what it might be?  Before the tech's start guessing, testing, and running up my credit card bill?  (cuz you know this one's beyond me). 

[cyclone]

Check your trans to make sure that you are not low on trans fluid. It is a very beefy trans for the application, probably just needs fluid topped off. Don't overfill it, though!

[blindside]

Two weeks ago I was using 2200 lbs in the back and 500 in the nose with the acme 13 x 11.5 3 blade and perfect pass and the boat held speed within .6 mph at 22 mph.  Waaaaaay better than I could have ever done manually

[cyclone]

Whaddya using for NN and KDW?

[blindside]

I was just using the factory settings.  I think the KDW was set at 170, can't remember what NN was set at.

[HCollado]

Wow, very interesting.

My boat is the standard 22, no V drive or S features. However, I run a 13X13 Right Hand prop. I see that just about everyone else is running on a left hand props.

I have been thinking about switching to a 4 blade right hand prop but boy are they expensive.?

[blindside]

Interstingly this morning I went riding with 2200 lbs in the back (700 in trunk and 1500 fat seat) and the perfect pass did not hold as well as it did with the 5-600 in the nose.  I am waiting on a call back from perfect pass to discuss.

 I want to get a clarification of if this statement is true.  "If I lower the NN it will adjust speed faster and if I raise kdw it will apply more throttle during the speed changes."

[blindside]

Got this on wakeboarder.com

From PP People.....
NN works like this:
Say you set it at 160, that means the system is measuring the time for
the last 160 paddlewheel turns and calculating the speed based on the
last 160 turns. When it sees the 161 turn it eliminates the 1st turn so
it is always using the last 160 turns. So when a change in speed
happens it takes a little while for the average of the 160 pulses to
decrease. Hence the higher you set NN the longer it will take for the
speed reading (average of all the pulses) to either increase or
decrease. The lower NN is set the quicker you will see a change in
speed reflected on your display. But if NN is to low say 60 and the
paddlewheel gets a disturbance for say 40 pulses then all of sudden the
system might think you have dramatically changed speed and make a huge
compensation when in fact the speed of the boat didn't really change.
But if you had the NN set to 200 it would average the 40 bad pulses in
with 160 correct ones and the system would ride out the bad pulses much
smoother.

Kdw
This is a bit harder to explain in a technically manner unless you are
familiar with electronic control systems. But it's easy to understand
in the real world. It's basically how aggressively the system will
react to changes in speed.

For example if you had a high KdW say 200 and the boat slowed by .5 mph,
the system would then apply additional throttle to compensate for the
change and regain the boat speed within lets say 1 second. If you had a
setting of 100 it may take 2 seconds. But the catch to this one is that
if it's to high it will not only compensate for the .5 mph it may shoot
the speed up to .3 mph over the set speed then .1 mph under then finally
to the correct speed, which will cause the boat to surge.

In Conclusion:
Now if you consider how these two values interact you'll see it can be
quite complex. If your NN is low and KdW is high, you might notice the
boat constantly adjust itself for no particular reason. If NN is high
and KdW is low the system will be much slower to react to changes in
speed and by the time it reacts there is already another change so it's
constantly chasing itself. It's usually best to adjust NN until you see
a nice steady speed on your digital speedo, with reason. And then tweak
the KdW for optimum performance.

[highflyn]

 
GREAT post
Thanks
Terry

[cyclone]

That was good, KDW is closed loop proportional gain for you control types. But you already know that.

My KDW is at 70, NN is at 120. I notice on other sites that everyone is using much higher numbers. Mine works fine but I don't load things down as much as some. WHat numbers are you guys using? I'm going to play around with it tonight and tomorrow.