How bad is this shaft?

[Ryan727]

Hey guys,

I've got two skis. One's a 99 hull with 98 motor. The other is a full 99'er. Primarily working on the 98/99 one as the motor is ready to scream, just waiting on a few last parts to come in the mail.

So in the meantime, I'm tearing down the 99'er to get ready to install my newer motor in it (came with a spare SBT motor).

It appears to me that this thing was ran in the salt water (That's 99% of our bodies of water round here), must have locked up, and it was just stored for two years since. No flush, no cleaning.. it's pretty nasty to say the least.

So I pulled the exhaust, chunks of salt pour out.. dealing with that later. Chunks of salt sitting in the manifold. Just a mess. Thank god I have a better motor for her.

I pull the jet pump, overall not bad - salvageable. But I'm wondering about this shaft, looks to be in rough shape.

What do you guys think? Just a nice wire brushing and coating will clean it up? Or is it time to lay it to rest? Are the teeth supposed to have that bend in them?

 

[Dr Honda]

Looks like a saltwater shaft to me.

Yes... the splines are "Balled" like that to allow a slight miss alignment when parts flax or shift. BUT, you should properly align everything to start. Also... make sure you have good waterproof grease in the PTO and impeller.

As far as the shaft... yes... buff it will a wire wheel. The question is... what does it look like where the carbon seal is?

 

[Ryan727]

Still working on pulling it out of the flywheel. Stay tuned, will have a pic within the hour. Where the input into the wheel is, it's clean steel - no rust inside the hull from the parts visible currently.

The ski wasn't submerged in salt water. But it sure as hell wasn't flushed. So my exhaust system is a mess. Go figure.. the only parts of the system I was going to keep with the swap.

 

[Ryan727]

But thanks for the initial answer - it is salvageable.

 

[Ryan727]

Okay, slightly over an hour. And excuse the pictures you're about to see - I already know I did it ass backwards. I removed the jet pump earlier, but couldn't get it back in to remove the float ring after reading it should be done that way..

But hell, the motor was already unbolted so I just moved that instead..

Here's float ring, carbon ring, and the shaft under the spring-boot:

 

[mikidymac]

I owild clean up the shaft and hit the seal area with some 2,000 grit wet dry sand paper. You are going to have to get an alignment tool now that you have unbolted the engine.

 

[Ryan727]

The engine is getting swapped with a working one I have spare (this one is seized), so that was inevitable. I plan on hitting the rusted shaft are with a wire drill bit, hitting it with a corrosion inhibitor, then some rustoleum clear coat - many layers (is that okay?), then finally some marine grease. Will clean up the seal area as well, with fine grit as you suggested. Thanks.

Saw another thread where Doc mentioned you're exposing the not-so-stainless area of the shaft when you grind it down. So I figured get rid of the rust first, and coat it for as much future prevention as I can get.

 

[mikidymac]

The shaft is a solid piece of stainless so I am not sure what the "not-so-stainless" would be.

 

[Ryan727]

Found this browsing the web - an old post relatively similar that the Doc had posted to:

How to clean up your rusty seadoo driveshaft

Welllllll...............


Actually... that's not a good thing. When you sand the surface of the stainless steel... you open the surface to free electrons. SO, if you are going to sand it clean... you need to pickle it again with an acid. (normally nitric acid) Otherwise, it may rust even faster. (especially in salt or high mineral water)

 

[mikidymac]

I know Dr. Honda knows more about these than probably anybody but I have done it this way and never had an issue. I know the standup guys cut and machine new splines in driveshafts all the time and in the salt water I have not seen an issue.

 

[Ryan727]

I was going to give it a coat of some rustoleum clear coat anyways. That shouldn't have negative effects, right? Can't hurt.. can only/maybe help kinda thing?

I'm even less knowledgeable than you. This was just my thought process, and makes sense in my head.. but what do I know. I just know if I sand it down it will come right back, I will only be running in salt water. I know it's impossible to fight salt corrosion, but I'm trying to get the longest life span as I can out of it. So I figure a coating per year should extend it's life a few years.