Amp metre

[Peter Blick]

Rebuilt my 250 crusader amp metre showing discharge when lights turned on. Turning ignition on the amp metre will not move to discharge no matter how many times ignition is turned on and off. I’m stuck on what to do next as need to do timing

 

[Philos]

Rebuilt my 250 crusader amp metre showing discharge when lights turned on. Turning ignition on the amp metre will not move to discharge no matter how many times ignition is turned on and off. I’m stuck on what to do next as need to do timing

I guess the obvious question is, why did you rebuild the amp meter showing discharge when the lights turned on? The needle should be centered on the dial face ( at the '0' mark).

Another important question is, are you talking with the engine running or not running?

 

[Peter Blick]

Sorry amp metre needle is in centre I rebuilt bike not amp metre amp metre works when turning lights on showing discharge but not working when turning ignition on which should show discharge

I guess the obvious question is, why did you rebuild the amp meter showing discharge when the lights turned on? The needle should be centered on the dial face ( at the '0' mark).

Another important question is, are you talking with the engine running or not running?

 

[Peter Blick]

No

Sorry amp metre needle is in centre I rebuilt bike not amp metre amp metre works when turning lights on showing discharge but not working when turning ignition on which should show discharge

no engine not running yet as have the problem I’m posting about as with amp metre not showing discharge with ignition switched I can’t fine tune timing

 

[Bluestrom13]

with amp metre not showing discharge with ignition switched I can’t fine tune timing

There are other ways -
The correct ignition timing is 30° advance ( 7 / 32 in. before T.D.C.) so that in the fully retarded position ( ie. not running), the contact points must open when the
piston is 5° or 1 / 64 in. before top dead centre.
First check the maximum opening of the contact points, which should be .014-.016 in., and adjust if necessary.
The adjustment is made by slackening the two screws holding the contact arm to the plate and setting the contact opening by means of feeler gauges.
The timing is adjusted by slackening the two screws holding the contact breaker plate to the crankcase and rotating the plate relative to the crankcase.

If the ammeter is non-functioning, then the point at which the contacts open can be determined by a light bulb and crocodile clips, or even, as in the "olden days", felt when they release a thin paper placed between whilst they are closed.

 

[Peter Blick]

Thanks

There are other ways -
The correct ignition timing is 30° advance ( 7 / 32 in. before T.D.C.) so that in the fully retarded position ( ie. not running), the contact points must open when the
piston is 5° or 1 / 64 in. before top dead centre.
First check the maximum opening of the contact points, which should be .014-.016 in., and adjust if necessary.
The adjustment is made by slackening the two screws holding the contact arm to the plate and setting the contact opening by means of feeler gauges.
The timing is adjusted by slackening the two screws holding the contact breaker plate to the crankcase and rotating the plate relative to the crankcase.

If the ammeter is non-functioning, then the point at which the contacts open can be determined by a light bulb and crocodile clips, or even, as in the "olden days", felt when they release a thin paper placed between whilst they are closed.

Thanks for your reply will try that way . Still don’t understand why amp metre shows discharge when turning lights on, but not showing discharge when ignition is switch on so strange

 

[Philos]

Thanks

Thanks for your reply will try that way . Still don’t understand why amp metre shows discharge when turning lights on, but not showing discharge when ignition is switch on so strange

From my experience that's exactly the way the ammeter works. The ammeter appears to be working as intended.

With just the ignition turned on (engine not running), there's very little power being drawn from the battery (a few dash lights only) so the meter reads around 'zero' mark. It's only when the starter is engaged that the current will flow from the battery to the starter, which will register a high discharge. Once the engine has started it'll take 5 or so minutes for the battery to be recharged. During that time the ammeter needle will move to the 'charging' side. After charging, it'll settle back down to around the 'zero' mark.

Any power being drawn from the battery without the engine running will show on the 'discharge' side of the meter, ie, power is being drawn from battery but not replenished.

Does that make sense?

 

[Andyb]

A 250 Crusader is kick start, not electric start, but otherwise what Philos says above is correct.

 

[Bluestrom13]

I believe OP is working on the fact that on old coil ignition with points machines the ammeter can be used to indicate piston TDC position - If it is working properly.

Still don’t understand why amp metre shows discharge when turning lights on, but not showing discharge when ignition is switch on so strange

So - in OP's instance, with ignition OFF, ammeter needle is at "zero".
Turn ignition ON - IF the points are open, the needle remains at "zero".
Turn ignition ON - If the points are closed, the needle should show discharge.
Depressing the kickstart SLOWLY should see the needle move to "zero", and the engine be in best position to kickstart.


Screenshots from HERE