ok here we go.

What we have here is a very old car with a very stupid idea. Rather than anything even slightly sensible, the person who designed this generator mounting decided to mount it on a post, that's right not a bracket like everyone else but a post! and to then tighten down that post by using a tapered bolt in a brittle cast iron head, AKA a nut splitter.


Description

I have just spoken to the previous owner, a very knowledgeable gentleman in his late 90's who admitted he too was having difficulty with this particular car and he could not prevent the generator descending over time and thus leading to a floppy belt Now he did suggest a fix and it would work but it would be very visible and I thought why not let the engineering brain power on here have a go at coming up with a better solution...

Before we start, I can confirm there is no crack, I have looked very very carefully. Tbh if there was a crack I think part of my engine would be on the floor by now. That may also be part of the problem as I am too scared to really tighten this thing up for fear of being the one after all these years who manages to break it!

On the photo I have highlighted with the two red lines where the post is and it goes from the side of the generator right through the head, the post is actually about 2 inch's long but it has slid down so you can hardly see it. It's tightened by the nuts arrowed that pull the tapered bolt up against a flat in the post. If its too difficult to imagine I may end up taking it off but I have to remove the top hose etc.

Good luck




[Edited on 30/1/24 by Mr Whippy]

So from above it looks like
FromAbove ?

It looks like the post needs to be roughly positioned, the taper bolt tightened to clamp it in place and then final adjustments made using the height adjustment on the side of the alternator? Is it possible to fit a slightly shorter belt, so the post can be clamped in the bottom position to start with and cannot drop? Can washers or a split packer be added to prevent the post falling below a height where the side adjuster can cope?

Overcomplicated maybe, but how about two slotted wedges, with teeth on the sloping faces? Position the post just higher than needed, slide the wedges in around the post, from opposite sides, toothed face to toothed face, until they fill the gap, drop the post just a fraction to lock the wedges together and clamp the post. The clamp would then be doing less work.

I've seen plastic version of the wedges, as adjustable packers. It must be possible to get metal versions, make them yourself or have them made.

[Edited on 31/1/24 by SteveWalker]

quote:

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Originally posted by coyoteboy
So from above it looks like
FromAbove ?

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quote:

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Originally posted by SteveWalker
It looks like the post needs to be roughly positioned, the taper bolt tightened to clamp it in place and then final adjustments made using the height adjustment on the side of the alternator? Is it possible to fit a slightly shorter belt, so the post can be clamped in the bottom position to start with and cannot drop? Can washers or a split packer be added to prevent the post falling below a height where the side adjuster can cope?

Overcomplicated maybe, but how about two slotted wedges, with teeth on the sloping faces? Position the post just higher than needed, slide the wedges in around the post, from opposite sides, toothed face to toothed face, until they fill the gap, drop the post just a fraction to lock the wedges together and clamp the post. The clamp would then be doing less work.

I've seen plastic version of the wedges, as adjustable packers. It must be possible to get metal versions, make them yourself or have them made.

[Edited on 31/1/24 by SteveWalker]

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could you make the post a little less slippy?
ie rough it up a bit, maybe just hitting it with a hammer, or a coarse file.

[Edited on 31/1/24 by gremlin1234]

Cut a slit into the casing vertically in a plane normal to the shaft ends. Take the vertical shaft and cut teeth into it. Proper teeth. Then replace your tapered bolt with a shaft with a spur gear cut into it, and a flat far end, with a hex socket in the outer end and a male thread on the outside. Use the hex socket to rotate the gear against the shaft to adjust height, then use the jam nut to clamp the casting halves together, without going too nuts and cracking it.

You wanted the most complex possible solution, right?

[Edited on 31/1/2024 by coyoteboy]

Mr W

What other pulley wheels does the belt run round - any tensioning possible somewhere else in the belts run?

Daft question I'm sure, but deffo the correct belt on there?

Measure the gap when it is correctly tensioned and have an aluminium collar machined up which can be inserted and then clamped together (ie, a ring with two halves) after the belt has been put on and correctly tensioned.

Quick fix would be a jubilee clip around the post ...

quote:

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Originally posted by nick205
Mr W

What other pulley wheels does the belt run round - any tensioning possible somewhere else in the belts run?

Daft question I'm sure, but deffo the correct belt on there?

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quote:

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Originally posted by Twobeers
Measure the gap when it is correctly tensioned and have an aluminium collar machined up which can be inserted and then clamped together (ie, a ring with two halves) after the belt has been put on and correctly tensioned.

Quick fix would be a jubilee clip around the post ...

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Description

Problem there is you won't be able to get the belt on if the collar is the correct thickness for correct tension, you'd need to stretch the belt temporarily to lift the shift and jam the spacer in.

Unless you took the old high risk belt fitting route and watch your fingers.

Thanks, but it should be fine as I plan to set the height of the post first and clamp in the normal way, then I will fit the collar simply to stop it sliding down after. I will get one that is very close to the normal exposed portion of the post.

quote:

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Originally posted by Mr Whippy

quote:

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Originally posted by Twobeers
Measure the gap when it is correctly tensioned and have an aluminium collar machined up which can be inserted and then clamped together (ie, a ring with two halves) after the belt has been put on and correctly tensioned.

Quick fix would be a jubilee clip around the post ...

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Yeah I think that is the best solution so far, I have found these things -


Description

They come in quite a range of thicknesses but I can easily add some washers to take up any slack, or maybe the clamping force will be sufficient to not require them. Paint it black and it's hardly noticeable. Thanks

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Well I hope so, this has been a frustrating issue since I got the car, leading to me almost breaking down several times as the battery is only a weedy 6v thing. Clamp ordered and arriving this week thanks all for the advice.

So the collar arrived today and I fitted it, a perfect fit and grips the post really tight. You'll notice I have left a gap at the top, this is to allow me to see if the collar alone does prevent it moving, if not I can add a couple of washers, however the belt is nice and tight.

Sadly we have snow here so I can't test the car till the roads are clean of salt but so far it has been a total success.

Thanks


Description

Oh yes, it may seem strange that it could move down at all being clamped, however I didn't mention that the generator is incredibly heavy, perhaps 3 times what you'd expect just looking at it. As all the parts, it's like their cast in lead!



[Edited on 8/2/24 by Mr Whippy]

Lets hope it gets nice and dirty soon so it doesn't look 70 years too new!

quote:

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Originally posted by bi22le
Lets hope it gets nice and dirty soon so it doesn't look 70 years too new!

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