Author Topic: Timing with a multimeter  (Read 1754 times)

Offline a101960

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Timing with a multimeter
« on: 11.04. 2009 10:56 »
I am about to set my timing (auto advance). Can I use my multimeter instead of the time honored fag paper? By that I mean using the buzzer facility on the ohms setting that is used for checking out continuity, and if so how do I connect it up? I am assuming that it goes across the points.

Offline fido

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Re: Timing with a multimeter
« Reply #1 on: 11.04. 2009 13:34 »
Yes, you can try it but remember that the magneto primary is always in circuit so the difference in resistance between points open and points closed is quite subtle. If the meter has crocodile clips, clip one to the bolt head in the centre of the points plate and the other to a convenient earthing point on the engine or frame.

Offline a101960

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Re: Timing with a multimeter
« Reply #2 on: 11.04. 2009 13:45 »
I have a supplementary question. Should the auto advance unit fly back when released from the advanced position (static) or does this only happen when the engine is running? I have reason to suspect that the auto advance is sticking. If it is is it possible to be freed up? Fido thanks for your reply I will give it a try and see if works.

Offline LJ.

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Re: Timing with a multimeter
« Reply #3 on: 11.04. 2009 13:46 »
I seem to remember John, that someone here borrows a friends buzz box to set up the timing and maybe what you have in mind, think it might be Brian not sure. But do a search of the forum, 'Buzz' might be the buzz word to use.

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Online RichardL

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Re: Timing with a multimeter
« Reply #4 on: 11.04. 2009 14:00 »
I would be surprised if a typical digital multimeter set to low range or autoranging can indicate fast enough to make it easy. If any meter, I would think an anaolg type with a needle to watch would be preferred.if any. If one hand a lamp circuit with a gate in it to recognize the small change in resistance one could easily judge "just open" from the lamp indiacation. otherwise, I found the rolling paper did just fine (first time I'd bought them in 30 years). Before you get to the lift in the cam use a hook of some kind to draw the points wide open to insert the paper, then, just lightly tug on it while rotating the points. The release point will be obvious.

As always, more experienced hans and minds will set me straight, if need be.

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Offline a101960

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Re: Timing with a multimeter
« Reply #5 on: 11.04. 2009 15:39 »
Well, I just tried the multimeter method, and I can tell you that it does not work, so fag paper it is then. I have thought about the advance and retard action a bit more. It will not fly back when fitted to the magneto in the static position because there is the drag/resistance factor from the cam ring and points heel to impede it. It snaps back readily enough when the mag is removed from the engine.