Need a better prop? UPDATE

[SpaceCowboy]

Interesting I’ve never understood set back if that’s what your describing. How thick of washer do recommend trying? To be clear your stating a larger gap between exit side of the impeller and pump fins?

The closer your prop is to the stater the better the pump loads. If you put a spacer in and it gets worse...prop is your issue. 1/4 should do the trick .

 

[ngerk]

Putting a spacer between the impeller and pump moves the impeller away from the stator veins which loosens the pump up. If you are slipping, this will actually make it worse.

Edit: sorry answered right after @SpaceCowboy

 

[catpower]

I need to see the shaft up close again but it appears I need to put a spacer washer on shaft first then install shaft in bearing so washer is resting on shoulder of shaft and also touching inner race of bearing. (Avoid it touching outer race) This will set shaft back so when I tighten impeller to shaft the impeller will “ set back” closer to pump veins. The idea is to get the impeller as close to pump as possible. Regardless of impeller pitch this will make pump more efficient. Have I explained this correctly. To bad this pump is time consuming to reinstall. Thanks for help.

 

[catpower]

 

[ngerk]

Just checking to see what you found out? The correct way to set an impeller back is to have the face of the mating surface machined on the impeller itself. Not sure if what you are wanting to try will work or not since it’s been so long that I’ve messed with a 140 pump.

Looks like you lost the intake grate inserts? Did you lose the grate as well? Any damage done to pump/impeller/shoe?

 

[newbee]

He said the grate was at the bottom of the lake. I have a big scoop grate on my ski as well but always silicone them in also.

 

[ngerk]

I just saw his other post. I hate that for him. Irritating when stuff like that happens.

 

[catpower]

I sent pump and impeller to Impros for repitch. Best I can gather from anyone running a strong 701 on a 140mm pump is I need a 10/16 or higher. I asked Glen at Impros about setback to make pump more efficient. I have epoxy resin I’ll mix with cabosil. I plan on welding a stainless 5/16” nut to a stainless washer and epoxy back in. I’ve read about a long bolt running up through hull under seat but I question drilling a hole into my pump shaft tunnel. If so no way to seal off water getting inside my dry refoamed hull. I glassed in the pump in photo used 3/4” pvc tube and made my own so called pump stuffer. Ya it sucks and if that wasn’t enough I snapped the steer shaft

 

[catpower]

Repairs made to intake grate and new steer post. The 9/15 was repitched to 12/18. I put an open grate back in. I now have much better acceleration. I guess the 140mm pump will never perform as well as a 144mm mag. I was hoping my X2 701 ski would pull as hard as my B1. Not gonna happen. Now if I can only get the HX water box to run a bit quieter.

 

[SpaceCowboy]

Repairs made to intake grate and new steer post. The 9/15 was repitched to 12/18. I put an open grate back in. I now have much better acceleration. I guess the 140mm pump will never perform as well as a 144mm mag. I was hoping my X2 701 ski would pull as hard as my B1. Not gonna happen. Now if I can only get the HX water box to run a bit quieter.

That may be more of a hull issue vs pump

 

[catpower]

mmmmn handling yes, but flat water straight line acceleration? The X2 has a smaller surface on water and weight can't be more. Both skis have flat bottoms. The X2 is more nose heavy.