Any dwell meter experts

Are the bearings of the cam drive worn and loose? This would badly effect the dwell.

Rob Graham

As would the shaft bearings.

Worn cam. Weak points spring. Play in the distributor bearings or cam to shaft bearings. Play in the baseplate pivot(s)

If it is wear in the distributor, an IR switched system like Luminition will give constant dwell.

what about shagged out condenser ?

This won't affect the dwell, although it might account for misfiring.

Rob Graham

Have replaced the condenser already. No difference.

Will look into the Luminition system.

I did notice that when setting the points with a feeler gauge it was possible to move the rotor/cam slightly, as normal, but it didn't spring back.

This is the only engine I service now, apart from garden equipment, and as I only do it once a year I have got very rusty. Either that or I'm past it.

In a rotary way? If so, that won't effect the dwell. If side to side, could be a worn baseplate. Many remember to put a drop of oil down the shaft, but not to oil this. (the top part pivots on the bottom as the vacuum advance operates.)

What make of distributor? It may be possible to buy a new baseplate.

the distributor would have to be falling apart to really make a lot of difference, just set it to 30 degrees of dwell, with new points.

mrcheerful

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember Paul Mc Cann saying something like:

Bent or worn distributor driveshaft and / or worn points cam. Have you any chance of finding the original specs for the distributor and/or a replacement? It's not a Lucas, is it?

Any chance the vacuum advance mechanism is playing up?

just my 2p

Bob

Worn out distributor.