Impellers other than factory but factory pitch, Which to buy?

[swatski]

Mad rpms surfing or wide open? Surfing running about 6300....max about 7400

Freaking perfect!

--

 

[J-RAD]

Mine showed up in the mail today. We'll see what I get out of these altitude adjusted ones.

 

[jacoviii]

No I just changed impellers. Yes from the 190 boat

So are your 6cw re-pitched or just as they came from Yamaha. Also as you said (good results on the low end) but how was the top end / wide open?

 

[swatski]

So are your 6cw re-pitched or just as they came from Yamaha. Also as you said (good results on the low end) but how was the top end / wide open?

I’m so anxious to do this!!! Unfortunately will be a couple of weeks for me.
I think he runs them stock and the 7,400 RPM at WOT with those longer blades will translate into high 40s close to regular if not better.

This is really good news for surfing.

—

 

[jcyamaharider]

So are your 6cw re-pitched or just as they came from Yamaha. Also as you said (good results on the low end) but how was the top end / wide open?

Factory Yamaha impellers unchanged, The boat didnt loss any top end. With 1300 lbs of people wide open on a calm morning we hit 45 with the bimini up.

 

[swatski]

Factory Yamaha impellers unchanged, The boat didnt loss any top end. With 1300 lbs of people wide open on a calm morning we hit 45 with the bimini up.

I believe this is the first official report of a 2015+ 240/242 yammie running factory pitched 6CWs (at ~sea level).
Awesome.

??? ?


--

 

[jacoviii]

This is great to hear. Now I need to chose pump cones first or 6cw

 

[jcyamaharider]

Try 6Cws first, they are much cheaper.

 

[J-RAD]

Finally found a moment to do the swap today. I haven't had a lot of trouble with cavitation lately, bit it'll be interesting to try them out and see what effect they have under load and regular performance. I HOPE we get out tomorrow to give it a try.

The double vice method with a 4' cheater Bar worked awesome! Thanks @swatski for the advice on the Husky wrench.

New 6wc impeller on top.

Questions:
1) Do the 4 main bolts holding the nozzle on need any form if loctite on then when reassembling?

2) I pulled the cones off to inject the bearings. Is there any special method to resealing those, or does the o-ring do the trick when properly seated? I notice the threads on those bolts had some form of white compound on them. Do I need to reapply something?

Thanks!

 

[buckbuck]

I use Teflon pipe dope on the threads of the bolts.

 

[swatski]

I don’t use anything on the long bolts.

I use anti seize on impeller. Anything to keep it from seizing is good.

I’ve used the factory grease inside and on the cone seal. Jeff cobra uses something, I would do what he does. I can’t look it up now.

—

 

[swatski]

I guess it's high heat silicone. Just don't pinch the cone seal!

You will know when they go bad. I learned that most people cause their own issues when it comes to the pump cones if you remove one you better be sure you reseal it good.
I use high heat silicon on the rubber seal when I put it back on.
I inject gear lube in with the bearing grease so the bearings are always lubed.
Yamaha has very reliable pumps I have new bearings sitting in a box just in case I need them but so far I don't I also never grease the intermediate bearings I remove the fitting and inject gear lube in that as well , no force behind it so no damage to the seals and if anything is going bad the gear lube will leak out and let you see that it's time for a new one .

 

[swatski]

Finally found a moment to do the swap today. I haven't had a lot of trouble with cavitation lately, bit it'll be interesting to try them out and see what effect they have under load and regular performance. I HOPE we get out tomorrow to give it a try.
View attachment 101752
The double vice method with a 4' cheater Bar worked awesome! Thanks @swatski for the advice on the Husky wrench.
View attachment 101751
New 6wc impeller on top.

Questions:
1) Do the 4 main bolts holding the nozzle on need any form if loctite on then when reassembling?

2) I pulled the cones off to inject the bearings. Is there any special method to resealing those, or does the o-ring do the trick when properly seated? I notice the threads on those bolts had some form of white compound on them. Do I need to reapply something?

Thanks!

I can not wait to hear your results with the 6CWs!!!!!!
I don't expect a miracle, but this is a mod I want to do as it makes so much sense. I even have the impellers already, but if it works I may invest in two new ones anyway while they are cheap.


--

 

[J-RAD]

I use Teflon pipe dope on the threads of the bolts.

Thanks @buckbuck!

I guess it's high heat silicone. Just don't pinch the cone seal!

Awesome, thank you!

I can not wait to hear your results with the 6CWs!!!!!!
I don't expect a miracle, but this is a mod I want to do as it makes so much sense. I even have the impellers already, but if it works I may invest in two new ones anyway while they are cheap.
--

I'm hoping for good results. There's a few locals I've encountered that I know are interested. @jcyamaharider's initial results sound great, so I'm optimistic.

 

[J-RAD]

The results for the 6WC impellers on my AR240 are in... and I'm liking them!

Conditions were pretty great so I ramped it straight up to WOT.



- 45.2 MPH GPS @~7500 RPM (highest top speed and RPM I recall witnessing)
- 4500ft Elevation
- Calm conditions
- 95% fuel
- Crew: 2 adults and 2 young children
- Bimini up


30 MPH at 5900 RPM (I can't recall prior)

It also seemed to improve mid-range acceleration, based purely off feel.

I did make a couple surf runs with full Transom Bag and 1/3 under seat and 2/3 ski locker. I wasn't on board to experience the loaded performance, but my wife said it seemed to pull fibe all the way up to 12 MPH.

Overall, I'm pleased with the results. Nothing lost and positive gains. I recommend them for anyone boating at elevation.
_

 

[swatski]

The results for the 6WC impellers on my AR240 are in... and I'm liking them!

Conditions were pretty great so I ramped it straight up to WOT.
View attachment 101831

View attachment 101830
- 45.2 MPH GPS @~7500 RPM (highest top speed and RPM I recall witnessing)
- 4500ft Elevation
- Calm conditions
- 95% fuel
- Crew: 2 adults and 2 young children
- Bimini up

View attachment 101829
30 MPH at 5900 RPM (I can't recall prior)

It also seemed to improve mid-range acceleration, based purely off feel.

I did make a couple surf runs with full Transom Bag and 1/3 under seat and 2/3 ski locker. I wasn't on board to experience the loaded performance, but my wife said it seemed to pull fibe all the way up to 12 MPH.

Overall, I'm pleased with the results. Nothing lost and positive gains. I recommend them for anyone boating at elevation.
_

Fantastic, pretty much exactly what I get - at under 1,000ft elevation!
That absolutely rocks, @J-RAD, thank for sharing, man!

--

 

[J-RAD]

Fantastic, pretty much exactly what I get - at under 1,000ft elevation!
That absolutely rocks, @J-RAD, thank for sharing, man!

--

I'm happy to be guinea pig

 

[jacoviii]

Fantastic, pretty much exactly what I get - at under 1,000ft elevation!
That absolutely rocks, @J-RAD, thank for sharing, man!

--

Swatski now you need to try them and see how they do at a lower elevation.

 

[swatski]

Swatski now you need to try them and see how they do at a lower elevation.

Yessir, I'm ahead, lol.
Already ordered a pair.

--

 

[jacoviii]

I thinking I will add these before the L13