Lets see if i can stump some guys with this one

[Cody87]

Okay guys, this makes absolutely no sense to me, but maybe someone can explain what happened here.

2006 150 Rude DI E150FPLSDR on a 377 DC javelin.

Took my boat out the other day with the 25 gade, and i dropped about 6-7MPH speed top end. The weird thing is, my RPM barely dropped, if any. The only thing is, i had just taken that prop in to be polished, and polished only. But i thought maybe he screwed with my prop. So with that being said, i took the boat out today with the 26 Raker.

No difference, dropped about 4-5 MPH with the Raker, with RPM not changing from normal.

The ONLY other thing i can mention is, the other day (before these two trips) i had a battery connection problem as my trim stopped working. But quickly figured out it was just a battery connection problem, but all is fine there now.

Do you guys have ANY idea what might have caused this? I'm so stumped, and kind of pissed, 5-7MPH drop is a big difference

[lkhartwl]

first thing you are running too big a prop with that motor and boat. you should be running a 24 raker or a 24 tempest for a 3 blade, since I dont run 4 blades I dont know them but I would drop a pitch. you should see your rpms go up and you should also see some speed, the battery has nothing to do with it . Now you also need to post your rpms, water pressure and if you have a jackplate or not and also your prop shaft to pad measurement to get a better help , also you since this is not really a motor issue try posting with the added info on the stratos boards

[torew]

GPS speed?

[Circle Hook]

Thats an easy one. You have a ding somewhere on the front of the lower unit causing bubbles to get to the prop and it isn't biting well.

Dayton

[Cody87]

Posted these results a while back, but here were the results a couple weeks ago. 4" below pad. Water Pressue at WOT is around 25. 5.5" manual jackplate.

27 Gade - 5000-5050 - 64.8 - Slowest to plane
25 Gade - 5450-5500 - 65.6 - Second best to plane
26 Raker - 5350-5400 - 65.8 - Third best to plane
24 Raker - 5750-5800 - 62.3 - Best to plane

btw, im not running too big a prop. The manual for this motor calls for WOT of 4750-5250. The 24 raker spun too high, and was the slowest regardless.

My results for the other day, with no real apparent reason for the slowness in speed was:

25 Gade - 5450-5500 - 57.9
26 Raker - 5350-5400 - 61.7

[Cody87]

Thats a good point, only i havent hit a thing since my last outing?? And there are no real dings that i can see....

[ChampioNman]

You would/could have mis matched the thrust washers could you? The washers for the Raker and Gade are different. Or you didn't leave them off all together did you?

[Cody87]

No sir! I keep a close eye on those!

[Lockjaw]

What were the props polished with? I would get some acetone and wipe them down and see what happens. Or 409, or some sort of heavy degreaser which would remove say.... wax.

Also if you went out on a hot humid day, that could have some inpact too.

I wish I could turn my 25p TR04 to 5500, my boat would fly then.

[Cody87]

LockJaw,

I have no idea what he polished them with, but i will take your advice and wipe them down, that is the only difference between the two runs, besides maybe a 10F increase in water temperature.

Air temperature between the two runs were identical, only about 15 degrees celsius.


Modified by Cody87 at 10:15 PM 4/25/2008

[hulapopr]

like the other post is that gps speed.if not i would see if your pitot tube is kicked up.tube kinked or something..don't really seem to be a polishing problem since it stayed with the raker,same loss.did you fill it up with more gas?if not it has to be a slip problem,double check what champ man said thrust washers,that's the only other thing to allow that much slip...

[Cody87]

yes, they are all gps speeds.

[Lockjaw]

The other thing I would be worried about is if in the polishing process, some of the cup was taken out.

Unless it was really humid, or you had your livewells full or something else, I just can't see where the loss went.

I hope you sort it out. I would love to have one of those DI motors.