Welding a hydraulic pump shaft

[Russell]

Has anyone welded a drive coupling to a hydraulic pump shaft? Did it bigger the pump? The spline on the drive coupling is very worn, the spline on the pump is also worn. I'm thinking if I drill a hole through the coupling and fill with weld and weld it through the hole the engine shaft goes in. I'm just not sure if the heat will kill the pump. I could use chemical metal but might not be as strong.

 

[Quattromike]

You could be on a hiding to nothing there.. hydraulic pumps have super high tolerances so any distortion would knnackker it. If the welding didn't go the seals. Is it a throw away item or prime mover your sorting up?

 

[Smiffy]

Seeing as you are drilling holes in the coupling you could try tapping them and putting a grub screw in
Or drill the hole fit the coupling put a drill bit in the hole with a very shallow grind on it then tap and fit grub screws
I don't know the design of the coupling but either a row of screws down one line or at intervals around the circumference should give a reasonable grip especially if it's reinforcing an existing spline even if the spline is worn

 

[Russell]

Good point I didn't think about grub screws although wouldn't the pump shaft be hardened? Ultimately it needs a new pump and engine so not to worried if it kills it but it would be nice to get a few more jobs out of it

 

[Canal Navvy]

Pump shaft will be proper hard , way too hard to indent with any drill I've ever met.

It's pretty easy to effect a temporary repair to keep going until the parts arrive using epoxy resin , though in my experience the new part turns out to be a new machine.

If my little Terex Schaeff had a similar problem I'd try using using the sort of resin that windscreen fitters use

 

[V8Druid]

Pump shaft will be proper hard , way too hard to indent with any drill I've ever met.

It's pretty easy to effect a temporary repair to keep going until the parts arrive using epoxy resin , though in my experience the new part turns out to be a new machine.

If my little Terex Schaeff had a similar problem I'd try using using the sort of resin that windscreen fitters use

Belzona, Devcon, JB Weld or Araldite plastic metal .. all would do a fair job ...... provided everything was perfectly aligned before application ..... and allowd plenty of setting time