Super Jet mid shaft noise

[Patrick Star]

How much noise is normal for rebuilt SN midshaft to make. I just rebuilt mine and it makes a kinda howling noise until it gets warmed up. I know new bearing makes noise, but this seems kind of excessive, being that it didn't make it on the first run, but started doing it on the second.

 

[Boris]

Shouldn't make any noise.
Does the shaft or carrier get hot ?
Sure you got it all aligned properly ?

 

[Patrick Star]

I checked it on the trailer and it didn't get too warm. The motor is aligned for sure.

 

[SJBrit]

But is the midshaft aligned? And the pump? You have to start from the back and work forward when aligning - all three driveline components can be shimmed.

 

[Patrick Star]

I spent awhile trying to get the pump shimmed/aligned in perfect and the mid shaft butted up flush against the bulkhead when I set it on the shaft. I used a card to align motor and got it all shimmed up over the course of 2 days. I didn't rush anything on this part.

 

[Freakrider]

I have learned that even with a new oem bearing the rubber lip of the seals rubbing on the midshaft generate some heat, the faster rpm the more heat ( which is normal)...double lips seals generate even more heat... my rebuilt 93 (gf's ski) howls too like yours but has been fine thus far ...

 

[Patrick Star]

I was taking it slow and easy the entire time on the first ride with a new engine and I haven't rode in a year+. I was thinking of just running and checking it frequently and if it don't stop once I'm through breaking it in then I may replace the bearing and seals and really align everything.

 

[SJBrit]

I spent awhile trying to get the pump shimmed/aligned in perfect and the mid shaft butted up flush against the bulkhead when I set it on the shaft. I used a card to align motor and got it all shimmed up over the course of 2 days. I didn't rush anything on this part.

But the midshaft may also need shimming against the bulkhead. When you slide it back onto the already mounted and aligned driveshaft, and slide it back till it contacts the bulkhead, you need to check whether it has made contact all round or whether you have gaps. Mine certainly came from the factory shimmed.

 

[Patrick Star]

It fit right up next to the bulk head all the way around. I did the pump and alignment first with nothing in the hull to distract or get in my way. I checked it like 3 times to be sure. I'll run it on the trailer to find out if it is starting to get hot or not now. The sound goes away after a minute of riding and the bearing has about a hour or two on it so far.

 

[SJBrit]

OK, cool: sounds like you did a really thorough job on the alignment.

 

[Freakrider]

It fit right up next to the bulk head all the way around. I did the pump and alignment first with nothing in the hull to distract or get in my way. I checked it like 3 times to be sure. I'll run it on the trailer to find out if it is starting to get hot or not now. The sound goes away after a minute of riding and the bearing has about a hour or two on it so far.

I wonder if the 90-93 smaller carriers make that howl noise and it's normal ? they are surrounded by less dampning rubber ?

 

[AtomicPunk]

I wonder if the 90-93 smaller carriers make that howl noise and it's normal ? they are surrounded by less dampning rubber ?

:smashfreakB:

 

[Patrick Star]

OK, cool: sounds like you did a really thorough job on the alignment.

Yea this and the electronics I took like 4 days to do, mainly just rework/checks since the electronics were totally disassembled. I put them together and checked them 4 or 5 times throughout the day and again in the morning when my mind was fresh, just to be sure. I read stories about smoking stators and stuff and this is a 61X JSS rebuild so I didn't want to ruin it. Same thing with the pump alignment, just put in in to take it back out to see if things are aligned. Stripped drive shafts and fried electronics tends to scare me cause they are so easily prevented.

Anyway I just got off work and took off the PTO cover and every thing looks great, fired it up w/out the cover and it just sounds like a bearing whine. I remember now that one time I put a new output shaft bearing on my Jammer (the engine had a midshaft too, it was crazy) and it howled for like a week or two and then went away. I used bearings from Pervert Bearing Supply (lol, Purvis Bearing actually) and that this rebuild kit was a WSM one so I imagine they are are pretty close in specifications/quality.

 

[Patrick Star]

I took it out in the surf and it's getting quieter now. I hadn't really rode the ski very fast or long at a time, but now it's getting better since I'm starting to ride it and not put around on it.