Help sorting out impellers for my two machines; SP580 and SPx800

[FaceDeAce]

Hi! I have been going through fixing and tuning a couple of old SeaDoo for the family funtimes. It has taken awhile to go through everything on each of them. I've got them running solid, reliable, and safe.

I finally got some lake time test running in yesterday. Based on how they ran,
..... --> I am looking for some help and guidance with respect to which impeller to put in which machine. Here are the basics of what I have;

The Doos
'94 BRP SeaDoo SP 580(587), stock
'97 BRP SeaDoo SPx 800(787), modified. Dual carb. Ocean Pro flame arresters, pump intake grate, FactoryPipeII, water injection, and hirev CDI.

The Impellers:
. 271000669 - I can't find any pitch info on this number (help!?). Closest to is seems to be 271000668 which lists as a 16-35 for a 720SP.
. Skat-Trak 16-21 super slim stainless.
. Spare 204160072 which looks like a 17-22 swirl.

( I have been looking at this link page for impeller info: http://www.seadoosource.com/impellerref.html )


Here is my current setup and issues.

--> The '94 SP 580. The impeller in it now is the number stamped 271000669.
This machine is running like a sluggish log dragger. Not reaching anywhere near full rpm from hole shot all the way to top water speed. I know everything else on this machine is fine (fuel, carb, plugs, etc). It runs well and solid. LS and HS needle adjustments had no effect. It is just really sluggish in the water - like and overloaded overpropped outboard boat motor. I know it is a 580 which doesn't have alot of power, but it should spool up much more than it does. So I really suspect the impeller in the 580 is just way too big / too tall. However I don't have a pitch gauge and I can't find a spec for that stamped number to confirm what is in there.

--> The '97 SPx 800. The impeller in it now is a Skat-Trak 16-21 super slim.
This machine rips up the algae (LOL!). Seriously it has tons of power, spikes to power band rpm quickly, and is fairly fast on the water. However, I suspect it has even more performance thrills to offer that is untapped by perhaps not having enough impeller behind it. It seems to top up and run a high rev really easily.


So I have one machine that I feel is overpropped and the other one seems underpropped and I have a spare. With the above info, which of the three impellers would be best installed in which machine?

Right now I am leaning towards:
1) Put the spare 204160072 into the SPx800
2) Put the Skat-Trak 16-21 into the SP580
3) Shelf the 27100668 from the SP580 until I find out what it is. If it is a 35 pitch prop - perhaps it would be better in the 800 for top speed?


Looking for some input and guidance please before I start taking things apart, again.

 

[FaceDeAce]

I did get time to do the prop swaps today and just got back from an evening ride.

-- Put the 16-21 skat into the SP580. I was right. It was overpropped. Now it runs Gr8!!! Logdragbog is gone. Spools up nicely now the way it should and cruises at a good clip too
-- Put the 27100668 into the SPx800. It pulled revs down a little overall. It doesn't grab quite as hard out of the hole but the top speed has gone up quite a bit!

Looks like I will not use the 204160072 just yet. I couldn't get it on anyway. There is something wrong with the threads as it would only go about halfway onto the shafts.

 

[FaceDeAce]

..........
https://vimeo.com/172072001


https://vimeo.com/172072331

https://vimeo.com/172072426

 

[dishgawd]

looks like you're having fun out there... that's what these skis are all about... thanks for sharing as I'm just about to change my prop to a higher pitch Solas with a new wear ring...(20-yr old GTX).. will let people know how I make out.

 

[FaceDeAce]

I have since put the 204160072 onto the SPX800. That machine now really RIPS up the lake. [emoji106][emoji4]. Very noticeable difference in hole shot. Literally jumps out when punched and it pulls like a tractor. Fast top end to boot. 50+mph.


Next for the SP580, I need to find a ride plate or trim tabs and better sponsons. It porpoises alot and is way too loose and squirrelly in back to my liking. I don't like being surprised by a back end breaking loose in a turn and a spinout into sliding backward at 40mph! I do like to spinout and do 360's, but I try yo keep those to happening only when I intend to.

 

[FaceDeAce]

 

[FaceDeAce]

https://vimeo.com/174824688