Impeller and wear ring install

[HotShotHarry]

Looking for recommendations on who to get to install wear ring on'15 Thunderjet envoy SD309 in Edmonton area. Also need advise on which stainless impeller to install. Boat weighs 2400 lbs empty. Kodiak 350 engine. The Athabasca river chewed up the stock aluminum impeller pretty quick. Having issues getting up on plane now. Thanks.

 

[Lund]

Looking for recommendations on who to get to install wear ring on'15 Thunderjet envoy SD309 in Edmonton area. Also need advise on which stainless impeller to install. Boat weighs 2400 lbs empty. Kodiak 350 engine. The Athabasca river chewed up the stock aluminum impeller pretty quick. Having issues getting up on plane now. Thanks.

Too bad your so far, i'ed doit for you. Its very easy to do bud. AT pumps are very basic and easy to work with.
The impeller some times can be cleaned up, i've clean mine up a few times.
The first thing a good shop would do is visually check the condition of the impeller and wear ring for tolerance with a feeler gauge and see if the impeller can be cleaned up and adjusted to the wear ring. All checks can be done without tearing anything apart and they then can advise you after the checks. I would avoid a shop that just tears into it as there is no need to do that.
The wear ring with an aluminum impeller would unlikely be worn unless one of the bearing's gave way. Most likely an impeller cleaning or replacement if it is really bad and shimmed to proper tolerance to the wear ring will fix it.

BTW, i would not recommend stainless impeller if your running river's shallow enough that there is a possibility to pickup rocks and gravel.
The drive on your jet is direct, a shaft connected to a u-joint, connected to the engine. There are no shear points to protect your pump and motor. Using a stainless impeller in such application is risky in causing serious damage to the pump and motor.
This is the purpose of the aluminum impeller, it is the sacrificial component and will fail first in protection of the rest of the drive.
Stainless is best suited for deeper water application or muddy river's but not gravely shallow river's.

 

[HotShotHarry]

Thanks Lund. I did pull the impeller and cleaned it up. The leading edge was chewed up some. It helped,but not for long. That's interesting info about using a ss impeller. Everyone around here recommends using it. Hmmm. Are you saying that I can check the wear ring tolerance without removing any parts?

 

[Lund]

Yes
You need a feeler gauge. Going through the inspection cover on top of the pump, remove the cover to access.
A long feeler gauge makes thing easier, it is worth buying one.
Look inside and you will see the impeller and wear ring.
Measure the tolerance between the impeller and the wear ring, it should NOT EXCEED .030, If it does have more clearance your pump is loosing pressure between the impeller and wear ring. The 309 pump is a pressure pump and not a volume pump and if these clearances are breached the drive goes to poop and the boat wont get up on step very well or at all.
You can tighten the impeller/wear ring clearance up to .025 MAX and no tighter, it makes a big difference in hole shot keeping the .025-.030 clearances.
In many/most cases it is just a simple matter of reshimming the impeller to get the pressure back.

Stainless steel has little to no give, in trashy water or in skinny water who ever gives you that advice is not giving smart advice. Yes it will take more trashing and abuse then the aluminum impeller but so will the drive have to take more abuse. With the right scenario and not hard to do on jet boat in river's, you could completely destroy the pump.

 

[Lund]

Here you go, this might help, print it off and put it in a binder;
http://www.americanturbine.com/downloads/pdf/oh_manuals/sd_oh_manual.pdf

 

[NoBrakes!]

The leading edge in your aluminum impeller must be Chewed badly or the shoulder/ radial clearance is terrible, if the impeller is hooped there's lots of choices.

A shouldered bronze wear ring will help big time. The you can shim the shoulder to .030". Depends on your impeller material but I'd stay away from stainless/aluminum wear rings. The shoulder clearance can be checked through the hand hole cover easily. We run billet steel impellers yes steel in our race boats down to .015" but it can be too tight for a stainless or aluminum. Precision billet impeller is the best money can buy, call Kimball if you want a real impeller.

http://www.precisionjetdrive.com/mall/prod04.asp

wear ring is a simple change, use a propane torch to burn out the insulator of the old one, put the new wear ring in the freezer for a few hours then use the old wear to beat the new one in place with a dead blow hammer. Then install an impeller to push it in straight then thread the nut on and torque it without shims until it's home. Remove nut/impeller, add proper shims and reinstall impeller/bowl. PM me if you want a phone call walk through. Roger Kehoe in Edmonton or Bernie at Outlaw will get you a proper wear ring.

 

[HotShotHarry]

Thanks for the replies guys. I pulled the impeller out again ,cleaned up the leading edge and removed the .010 shim. I will try it out today. Any one try out the Inducer Impeller?

 

[NoBrakes!]

inducer will help get up on step but requires machining the shaft... had one in a tunnel, helped the bottom end but hurt the top

 

[174mcx]

I believe if you run shallow water you should have a steel impeller. If you continue with the aluminum you will continually be removing it and sharpening it as well as welding it up to rebuild removed material. Ive seen 309's that after a couple gravel bar encounters would not work well enough to get the boat back on step, resulting in a difficult task getting them back to the truck.

As far as which impeller to get, you will loose about 200rpm with the same impeller in steel as what you have in aluminum. So you can judge by that, if you have an "A" (I assume this is what you have) and you like the performance stay with an "A" if you want more rpm go to a "B" and if you want less go with a "AA" and so on. You will also notice a rattle at idle with a steel impeller, thats normal, if you follow the american turbine impeller change directions you will have no problem, its easy to do yourself. I always removed my stomp grate to check the tolerances, it made it alot easier and gave me more confidence I was doing it properly. Reaching through the clean out cover works but you cant see what your doing, you have to do it all by feel at that point.

 

[S.W.A.T.]

I believe if you run shallow water you should have a steel impeller. If you continue with the aluminum you will continually be removing it and sharpening it as well as welding it up to rebuild removed material. Ive seen 309's that after a couple gravel bar encounters would not work well enough to get the boat back on step, resulting in a difficult task getting them back to the truck.

As far as which impeller to get, you will loose about 200rpm with the same impeller in steel as what you have in aluminum. So you can judge by that, if you have an "A" (I assume this is what you have) and you like the performance stay with an "A" if you want more rpm go to a "B" and if you want less go with a "AA" and so on. You will also notice a rattle at idle with a steel impeller, thats normal, if you follow the american turbine impeller change directions you will have no problem, its easy to do yourself. I always removed my stomp grate to check the tolerances, it made it alot easier and gave me more confidence I was doing it properly. Reaching through the clean out cover works but you cant see what your doing, you have to do it all by feel at that point.

What he said^^^^^

Your boat is pretty light so I'm guessing your not reving up that high. Stainless is by far the way to go for reliability. And this is a easy switch you can do yourself. I just did the old YouTube thing the first time.

 

[NoBrakes!]

I mean carbon steel, strongest made. Not cast, fab welded from a few pieces.

 

[174mcx]

I agree NoBrakes, those are beautiful impellers you referenced, I found them a little pricey for all I wanted and just got the "stainless" ones from Bernie. I hesitate with the "stainless" because all the ones I have been near would let a magnet stick to them so they have a fair bit of carbon in them. I think the stainless name is used to make people think there shiny! shiny is better you know!

 

[neilsleder]

I agree NoBrakes, those are beautiful impellers you referenced, I found them a little pricey for all I wanted and just got the "stainless" ones from Bernie. I hesitate with the "stainless" because all the ones I have been near would let a magnet stick to them so they have a fair bit of carbon in them. I think the stainless name is used to make people think there shiny! shiny is better you know!

There’s never carbon in stainless steel. Carbon will destroy the properties of the stainless. It’s the nickel content that makes it magnetic.

Carbon steel don’t rust when sitting to bad? Then rust solid do to tight tolerances? Not familiar with these pumps so not sure how they are set up just thinking out loud.

 

[HotShotHarry]

inducer will help get up on step but requires machining the shaft... had one in a tunnel, helped the bottom end but hurt the top

What machining is required? A keyway?

 

[174mcx]

Good to know on the nickel content, I always just checked with a magnet. learn something new everyday thanks!

 

[HotShotHarry]

What he said^^^^^

Your boat is pretty light so I'm guessing your not reving up that high. Stainless is by far the way to go for reliability. And this is a easy switch you can do yourself. I just did the old YouTube thing the first time.

4300 rpm.

 

[HotShotHarry]

Ok.... so I tried it out yesterday. 3 people ,full tank of fuel. The river is running about15-20mph right now. Boat gets up on step fairly easy but I have to feather it in or it will still cavitate. Once up on step,the boat works awesome.

 

[HotShotHarry]

Lund states some pretty valid concerns using stainless in a muddy,gravelly river, which this part of the Athabasca is. I like the looks of the billet impeller, but wonder how long it would last. Ya Ya I know... Quit hitting the gravel bars and you wont have any problems, Lol.

 

[Lund]

Go on Meanchicken and contact RON at ATM, he is the AT rep. go to the sponsor page. Send him a pm. or start a new thread on his page.

 

[NoBrakes!]

We have YEARS of racing on these billet impellers. they're coated black and only surface rust when sitting. Kimball also makes a 4 or 5 blade impellers. Aluminum as well in both.

I run stainless AA in every play boat I've owned. never had an issue with stainless and shouldered bronze wear rings. the shoulder is key to getting out of the hole.

the inducer requires a keyway and shaft OD machining to allow it in front of the impeller. the shaft shoulder needs to move the length of the inducer.