Super Jet Blew Pump Bearing in 1 Hour - help

sneds

sneds

Location
Wasaga Beach
I will appologize in advance for the long winded explaination, but I don't want to miss anything that might be important.

I put my freshly built FS-2 in the water for it's first ride two weeks ago and after an hour of riding the engine stalled on me. My first thought was... out of gas but, when I got it into shore and lifted the hood I found that I had plently of gas. I tried to start it and right away I shut it down. The pump made a ton of noise and was vibrating a lot more than normal. I flipped the ski on its side to check if anything was lodged in the pump but couldn't find anything. I loaded the ski on the trailer to take a better look. The drive coupler spinned perfectly, everything looked ok. After bringing the ski home and pulling the pump out of it, it became very apparent what the problem was. One or both of the bearings were done, the drive shaft wouldn't spin freely. It would rotate, but it jams up and it takes a bit of force to overcome the resistance. I don't have the impeller off yet to take a better look, as I don't have the tool to hold the shaft. What could cause a brand new bearing to go so fast? Could it be so simple as a bad bearing from Yamaha?

The following week, I installed the stock pump to get a better idea of what could have caused it. With the spark plugs out, the drive shaft spins freely and I don't notice any binding (It gets a bit harder to spin when the pistons hit top dead center but other than that, I don't feel any resistance). I know most of you are thinking "alignment" but I installed the pump and midshaft as per Rick Roys instructions so, I don't believe I have an alignment issue. Is there any way of telling? (other than the drive bearings don't last) Even if I do have an alignment issue, I wouldn't think the bearings would last longer than and hour, right? To give you a little more information... The pump is a Solas 12 vien Mag pump, the drive shaft I bought used from this site and is a "mint" OEM shaft, bearings and seals are OEM and I packed the bearings, pump, and nozzle full of marine grease.

I put the ski in the water last week with the stock pump and ran it an entire day without any issues (yet). So I'm stumped... I really don't want to rebuild the pump and put the time and money into another set of bearings and seals just so they will blow right away. I would prefer to get to the root of the problem if I can.

Any help would be appriciated.

Thanks,
Sneds
 
kevbo

kevbo

Location
dfw
How tight did the bearings fit the SS pump? If a lot of pressure was required to install the bearing its internal clearance could have been taken up. A 6205C3 is ok for mild press fits, a 6205C4 may be required.
 
ScottS

ScottS

X
Site Supporter
Location
Savannah, GA
It's probably not a bent drive shaft, he probably did the same stupid move that I did when I first installed my Solas pump. When I removed the drive shaft out of the stock pump, the bearings were stuck on the shaft. Instead of removing the front bearing from the shaft and driving it into the new pump with a large socket by the outer race, I decided to heat the pump housing and freeze the shaft.

When I went to slide the shaft and bearing assembly in, it went 3/4's of the way by hand and then stuck. I took a brass drift and drove it the rest of the way by tapping on the back end of the drive shaft. That forced all the pressure on the inner race of the front bearing and cracked the retainer.

One hour into the first ride, the bearing retainer on the front bearing came apart. The rear bearing supported the shaft and allowed me to ride it in, but it made hellish noise. Lesson learned, never drive a bearing in by the inner race.
 
waterfreak

waterfreak

I had a vision!
Site Supporter
Vendor Account
Location
s florida
In order to properly install the bearings and shaft into a new pump, you need a press.
There is no need to heat anything up and pounding the bearings in may end up with damage to them.

just a thought!
 
kevbo

kevbo

Location
dfw
waterfreak said:
In order to properly install the bearings and shaft into a new pump, you need a press.
There is no need to heat anything up and pounding the bearings in may end up with damage to them.

just a thought!
Click to expand...

Heating an aluminum stator even a little makes the process much easier. Steel stators usually end up needing a press unless you have access to liquid nitrogen and are sure the fit is not to tight.
 
sneds

sneds

Location
Wasaga Beach
First of all, thanks for all the feedback!

Ok, to answer a few of your questions... I couldn't get the impeller off the stock drive shaft so I had to buy a whole new setup. So, the drive shaft, bearings, seals and pump housing are all new and my backup pump assembly is my stock pump that I couldn't get apart (stock driveshaft, bearings and seals). They are two totally complete setups. I was able to install the front bearing onto the drive shaft by hand and a few gentle taps of a mallet. I made a tool that fits over the end of the drive shaft and presses on the outer race when installing the driveshaft and front bearing assembly into the pump. I used an arbor press to install both the bearings into the pump housing. Once the first bearing and drive shaft were installed I packed the pump housing with marine grade grease, then pressed the rear bearing into place. Filled the pump nozzle with grease and installed the nozzle. Because I used an arbor press I don't know how much force was required to push the bearings in, but if I had to guess, it was a fair bit.
 
sneds

sneds

Location
Wasaga Beach
One other thing worth mentioning... After looking at the two drive shafts I noticed my stock drive shaft seems to taper a bit after the midshaft spline (teeth) portion and remain thinner all the way to the impeller. The new drive shaft doesn't have a taper at all. The shaft is the same width from the teeth section to the impeller. I was told the new shaft is an OEM shaft but the two look different. Maybe the shaft in my stock pump isn't stock? Or my new one? I only bring this up because if my new drive shaft isn't an OEM, than maybe that has something to do with it??
 
sneds

sneds

Location
Wasaga Beach
Also, when installing the bearings into the housing I had to use the arbor press the entire way. The bearings would not go in at all by hand.
 
D-Roc

D-Roc

I forgot!
Location
Dirty River Rider
My oem bearings slide in my oem pump really easy. I heat the stator hub, keep the bearings at room temp and freeze the driveshaft. My oem driveshaft has a taper. I support the races with various pipes and never used a press just tap with a mallet. Not the correct way but has worked for me
 
snowxr

snowxr

V watch your daughters V
Location
Waterford, MI
sneds said:
One other thing worth mentioning... After looking at the two drive shafts I noticed my stock drive shaft seems to taper a bit after the midshaft spline (teeth) portion and remain thinner all the way to the impeller. The new drive shaft doesn't have a taper at all. The shaft is the same width from the teeth section to the impeller. I was told the new shaft is an OEM shaft but the two look different. Maybe the shaft in my stock pump isn't stock? Or my new one? I only bring this up because if my new drive shaft isn't an OEM, than maybe that has something to do with it??
Click to expand...

I think you were misled about the "oem" driveshaft. It was likely much longer when it was an oem shaft in a couch. Then someone cut it, and put new splines on it.

When you used the arbor press, did you push on the middle part of the bearing? That could ruin it.
 
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