Water pump problems with a 102

[Rob Ripley]

The pump works fine - too fine.
I'm rebuilding a 102 from parts and found that after I put the gearbox together it also pumps water out the relief holes in the drive shaft.[attachment=1]P6050003a.JPG[/attachment]
There is no bearing above the water pump (on any of my motors). I tried with a plastic washer but it did not help at all. I wonder now if I could fit a lipped oil seal?[attachment=0]00001.jpg[/attachment]

[Charles uk]

Rob the pinion & the waterpump impeller & perhaps the gearbox as well are from a Wartime SD but the water pump housing is from a later model that has no provision for a above the water pump impeller bearing, the SD equivalent has a bearing above the impeller & a 1/4" hole that seems to be for pressure relief in the side of the impeller chamber.

The moral of this story is " if you shuffle bits to create a bitza, expect glitches"

[Horsley-Anarak]

I made a nylon bush for my TC, that stopped the water going up the leg.

H-A

[Rob Ripley]

Here is a pic of AD48108 with the gearbox assembled and pics of 2 other 102 gearbox cases (they have stripped gears and/or broken studs.

[attachment=0]#2 007.jpg[/attachment]
[attachment=1]#2 001.jpg[/attachment]

[Charles uk]

Those are the right bits Rob, for an early AC or AD, can't see well with that green paint but there's a very good chance that that leg would have had a phosphor bronze "cotton reel" bush at the bottom end of the drive shaft tube.

Your pinion shaft looked a little to damaged to support with a new bush, but you'd have to check.

I've seen Cuda boats in Melbourne that had local wood prop shaft bushes that were oil impregnated, try a timber bush that's been boiled in oil with a 10 thou clearance hole, that would slow down your water feature & you could grease it if you built it right, I don't have a cotton reel bush out that I could photo & measure but I'm sure someone else will be able to post the size/design info.

Sorry I called it a Bitsa!

[Rob Ripley]

[quote]but there's a very good chance that that leg would have had a phosphor bronze "cotton reel" bush at the bottom end of the drive shaft tube.[/quote]
Not now.

[quote]Your pinion shaft looked a little to damaged to support with a new bush, but you'd have to check.[/quote]
Yes, it is a bit rough, I might be able to clean it a bit. Thats why I was thinking about an oil seal.

[quote]I've seen .... that had local wood prop shaft bushes that were oil impregnated, try a timber bush that's been boiled in oil with a 10 thou clearance hole,[/quote]
As a wood turner by trade, I could try that (don't know about the 10 thou clearance) probably better to turn up a nylon bush.

[quote]Sorry I called it a Bitsa![/quote]
No problem ... It's about as original as I can get.

[Charles uk]

All it needs is a close ish fit, it doesn't need to touch the bush just to make make the waters path a little more difficult.

[StephenRT]

I've just photographed and measured one of my bushes.The bush is a sliding fit on the shaft and seems to be made of brass.
Hope this helps
Steve

[Rob Ripley]

I forgot to say a big THANKYOU to StephenRT.

[Rob Ripley]

I think I done it!
Found that a recycled plastic garden stake was sufficient size. I bored and turned it on my wood lathe to match the dimensions on the picture. Possible water pump test tomorrow.

[attachment=0]00001.jpg[/attachment]

[Charles uk]

Try boring the pinion hole in the bush 10 thou under size then heat shrink it on to the pinion shaft it will only have to be 1/8 deep on the od which will rub itself away on the id of the drive shaft tube until it gets the clearance it needs.

You could make it like an inverted top hat with a hole in the crown for the shaft & rest it on top of the water pump impeller, the square drive shaft will stop it coming off the top.

[Rob Ripley]

[i]Try boring the pinion hole in the bush 10 thou under size then heat shrink it on to the pinion shaft it will only have to be 1/8 deep on the od which will rub itself away on the id of the drive shaft tube until it gets the clearance it needs.[/i]
Not at my level of expertise and only available mechanical equipment is a woodlathe.

[i]You could make it like an inverted top hat with a hole in the crown for the shaft & rest it on top of the water pump impeller, the square drive shaft will stop it coming off the top.[/i]
Actually, I was able to do that.

[Charles uk]

Should have kept my mouth shut!

Let us know if that fixes the problem.

[Rob Ripley]

I'm sorry Charles I did not mean to offend you ... I'll accept any advice, and see if (with my limited ability and equipment) I can put it to use.

[Charles uk]

None taken, I had a smile on my face as I typed that,