Right need some ingenuity

[DrNik]

I have a mini moto which is playing up, and not cooling the engine, well the water pump pulley goes round, but you have to split the crankcase to get to the impeller, so the impeller is spinning on the shaft and as I don't want to split it again I need a perfect fix, so I can fit it and forget it, I thought of jb weld, or drilling and tapping the shaft and bolting down, shaft is stainless steel and impeller is plastic, see pics

 

[dannyp]

i'd be tempted to try and stick it.

 

[DrNik]

That's 1 for jb weld then

 

[CompoSimmonite]

As well as JB Weld can you also cross drill and add a roll pin or similar ?

Paul H

 

[MattF]

As well as JB Weld can you also cross drill and add a roll pin or similar ?

That's the method I'd go with. Wouldn't trust an adhesive alone.

 

[DrNik]

May be able to jb weld and then drill a tiny hole across the shaft and break it off inside

 

[dannyp]

i'm not sure on pinning it, it would defantly have the feel better factor but surely for the pin to do anyting the JB weld will have given up, then then pin is going to be doing all the work and i would have thought its going to chew its way out.

really need to know dose JB weld stick well to said inpeller ?

other option is sopose are making an inpeller out of ss or a whole one piece assembly ( but that would be hard work )

i would like to say drill nd tap a hole in the end of the shaft and then sandwich teh inpeller with a shaped washer that locates ont he vanes but said bolt may be to small to be of any real use. it i a tricky one

 

[captain-destructo]

drill it and how about a copper rivet?

 

[zzr1200]

How is the impeller driven by the shaft under normal assembly, in one picture the shaft appears to have a keyway and in another one there seem to be a drive tongue on the end of the shaft???.

 

[Fintray]

Loctite 620 may be what you need.

 

[J_K]

Not seen Araldite or similar Epoxy glues last long where there was any heat...
Not sure about JB weld but might be worth trying to find a data sheet on it and see what temps it can withstand.

 

[DrNik]

The impeller is driven by a drive pulley on the threaded end by the flat ground into the shaft, the impeller just pushes tight upto the raised band, there isn't even a flat part inside the impeller for it to catch on the flat of the shaft, it's pure Chinese crap engineering, having a spline on the shaft and then moulding the impeller on the end would have been so much better, but when they are pumping them out fast, who cares, till it blows up

 

[DrNik]

I could tig a washer on the end of the shaft, that would be the easy bit

 

[normspanners]

The impeller in most pumps, take quite a lot of driving comparatively IMO and plastics break free quite easily, especially when the water gets a little 'thick' due to frost etc.
I presume you have it stripped ATM and have it in your hands, coz you have the pictures and you state you dont want to strip again, so you want to fix and forget , I would make a stainless impeller the most accuracy required is the length of the fins IE the closeness to the body of the pump on the far side of the pump away from the pulley the dia is not super critical . All you would need would be a stainless repair washer and tig some fins on it then tack weld the washer to the shaft and machine the ends off the fins to suite.

 

[DrNik]

Think I'm going to have a go at making a stainless steel impeller from a couple of stainless washers, and the once I've cocked it up I can weld it on the shaft,don't suppose I need to have the fins curved although it might help a little, after all it's just flinging the water to the outside edge

Just had a brainwave I could get 2 washers, and slit the top one and fold it up to make the vanes less crappy tig work for me

 

[zzr1200]

If you have or know someone with access to lathe, would it not be possible to make an impeller and shaft out out of one piece of s/steel?

 

[Burdekin]

Is this the same as you have? http://www.ebay.co.uk/itm/Water-Pum...11?pt=UK_Motorcycle_Parts&hash=item2585a61d83 £8 for a new one and maybe a bit of of JB weld will help it last a bit longer.

 

[normspanners]

A lot of impeller fins are just straight ie square with the 'cord'but you could put them still straight but with a slight angle to form a scoop.

 

[wookie]

The impeller in most pumps, take quite a lot of driving comparatively IMO and plastics break free quite easily .... I would make a stainless impeller .... All you would need would be a stainless repair washer and tig some fins on it then tack weld the washer to the shaft and machine the ends off the fins to suite.

I completely agree, I'd make a new impeller in stainless and weld it onto the shaft, it will probably outlive the rest of the machine, plus you get to Tig weld some stainless, it doesn't get any better that that I used to tig weld stainless for a living nearly 20 years ago and I loved it.

 

[Lawnmowerboy]

I would put a light knurl on the end of the shaft and stick with correct locate.