Bevel Gear Meshing

We took our Ruston & Hornsby horizontal diesel engine over to Holland a couple of weekends ago, the the Dutch Whitsun holiday, to the Nuenen Engine Show.
No problems with anything vehicular or engine-related, but we had an annoying grumble from the engine rev-counter, a separate instrument made by Harding (Leeds) Ltd for Ruston & Hornsby.
Everything was well oiled or greased, but the gears were rough to rotate and noisy.
I've been in touch with the successors to Hardings, Foundrometer Instruments Ltd., but they have not kept any records or drawings of the Harding products.
Looking at the gears, they seem to have some clearance, the gear edges are aligned and I cannot see where the noise is coming from.
The guy at Foundrometer suggested running them together with fine grinding paste, but before I do that, I'd like to ask for any thoughts and suggestions here first.
The gears are pinned to their respective shafts, both run in double ball races, we did try Moly grease as well as oil.
There is no obvious meshing adjustment either. The engine has only done 400 or so running hours, so isn't worn to any degree.
Any thoughts?
Peter -- Peter A Forbes Prepair Ltd, Rushden, UK snipped-for-privacy@prepair.co.uk http://www.prepair.co.uk http://www.prepair.eu
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Hi Without hearing and seeing the set up it is hard to advise, however I would not go for the grnding pade option. Assuming that he two shafts are in the correct position, are aligned OK and the gears are not damaged, the problem will be with the actual meshing. This can only be adjusted by moving the gears along their shafts (or moving the shafts to get the same result). If you do this there will be a sweet point where the gears run OK and you will have to locate them there. Peter
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Drawfiler wrote:

Seconded!
The grinding paste is likely to get embedded in the gear surface unless they are hardened. You then have a pair of bevel grinding wheels that will slowly destroy themselves. To be avoided IMHO
Bob
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On Tue, 08 Jun 2010 10:39:36 +0100, Bob Minchin

Thanks, Peter & Bob:
Moving the dial head upwards and drawing the top gear out of mesh eventually makes an improvement, but that is almost 1/8" before anything noticeable happens.
I'm going to take a skim off the tops of the gear teeth as there seems to be a burr thrown up that is catching the gear face. Not sure where the burr has come from though, there's a single small mark on every gear face, not what I'd have expected from a bevel gear pair.
I'll report back when I've done that.
Thanks again,
Peter -- Peter A Forbes Prepair Ltd, Rushden, UK snipped-for-privacy@prepair.co.uk http://www.prepair.co.uk http://www.prepair.eu
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