Freestyle snapped driveshaft,who knows the size and pitch of shaft on rear

driveshaft snapped inside impeller,best way I see to get this off is put a nut on the rear,I tried a m20 1.5 pitch like the pitch gauge seem to indicate,but no go?seems like less trouble than welding a bolt in it
 
I could try that,but the metal looks a little thin being hollow to get a good grip,if I knew the nut size I could order another from fastenall
 
I can't remember what the pitch was, but I did the exact same thing to remove. We found a nut off of on of Skinnyman's pit bikes that fit. Seems like it might have been the nut on top of the forks.. Sorry I can't be of more help.
 
the weird thing is a pitch gauge read 1.5 and it was a m20,but when i got the nut it was off just a tad and wont thread on
 

Matt_E

steals hub caps from cars
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at peace
Had the same thing happen to me last winter. If you search, there's a thread on it.
I ended up cutting the stator section if the pump off (destroying it), then grinding flats on the shaft behind the impeller.
 
Masterblaster, it's a 20 x1.5 like you tried. Someone might have installed this shaft with a hammer before and somewhat mushroomed the end of the shaft. Grind down/bevel the first 2mm and see if the nut will go on then.
 
it did start to thread,went on 3/4 turn and then locked up like wrong pitch,i was like whatever and put a big wrench on it and it sheared the first couple threads off the end of the shaft and fell off,errr.i have a bolt in it now just gotta make time and go get it welded,knowing my luck the prop will be stuck even with heat on it and the weld will break before the prop spins loose
 
theres no shaft to ice it broke off inside the prop,i might try lowering the threaded nub in some cold water and then hit it with a air impact
 
suppose that might get it moving,gotta be careful,its a nice 10/16 hooker i dont wana warp and the pump is a pretty thin ported hp setup,best pump ive ever used that wasnt a mag
 

Matt_E

steals hub caps from cars
Site Supporter
Location
at peace
When that happened to me, I wanted just the impeller out of the deal. The stator section was already damaged a bit. The heat will discolor the impeller, fyi.
 

OCD Solutions

Original, Clean and Dependable Solutions
Location
Rentz, GA
Pump stators are cheap, I've got two on the shelf I have no use for. Just cut it off to expose more of the shaft and start fresh.
 

OCD Solutions

Original, Clean and Dependable Solutions
Location
Rentz, GA
check out post 14,this one is really nice with alot of work done to it

I understand that but sometimes the sacrifice will get you further ahead in the long run.

Imagine how i felt when a brand new Impeller galled the threads on the brand new shaft of my brand new Mag Pump. I was sick for hours stressing over it but finally packaged it up and sent it back to Skat, they had to cut the impellor off the shaft and then ended up ditching the shaft too. They sent it back to me with a second shaft and impellor on warranty. This time they verified the threads and assembly before shipping it out.

I have had great luck drilling out shafts from the center and slowly increasing the hole until the material is thin enough to give way. I have a couple long reach carbide tipped deburring tools that were very expensive 15 or so years ago when i bought them but have been worth their weight in gold for situations like these. just be patient and keep grinding away at it then. Really, if it takes you several hours of tedious grinding to remove the shaft, you are still ahead if you can salvage your pump and impellor.
 
i have debur bits,I use them from everything from porting to shaping,they do come in super handy,but i dont have the patience to grind out the hardened steel shaft,billet is bad enough,this frikin weld better hold

I once trench clearanced the bottom of cases for a 5 mill crank with them and a circular grinder,that was bad enough,total loss of sanity
 

OCD Solutions

Original, Clean and Dependable Solutions
Location
Rentz, GA
"Life is ironic isn't it? Just a few posts up I told someone to suck it up and just cut the stator off. Well, my wife sheared the driveshaft on her SJ this weekend and it was on a 140mm 8-Vane Mag pump and there was no way I was cutting the stator off. I remembered reading this thread and some of the solutions others had tried.

The shaft is thin and hollow so grinding or clamping just deforms the end. I searched thru all my bolt bins and could not find a matching nut. I spent about half an hour sifting thru my toolbox looking for something that could be modified or adapted and ended up settling on a simple narrow cold chisel. I had to grind it slightly but was able to drive the tapered head of the chisel into the end of the shaft and then capture it in my vise. I then heated up the impeller with a propane torch and hit it with an impact gun for about 5 mins and it popped right off. All in all it took less than an hour and a half to replace the shaft and get the pump back in the ski.

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