Export thread

Hello everyone,

I have had a charging problem with my 12hp Westwood T1200 for a few years now and I have finally got round to fixing it.
The problem basically is my battery is not charging.
I have done a few tests on it using my multimeter and found out the alternator is working correctly.
The battery is new and there are no problems with it.
Electricity is leaving the engine but is not getting to the battery to charge it up.
I have installed a new circuit board so its not that.
My suspicions are its something related to the solenoid?
I have just changed the inline fuses and one was broken so I replaced it and the battery is still the same, no charge so its not that.

I really am stuck if its not the solenoid. :confused2:

Does anyone have any ideas of this? Anything would be much appreciated.

Thanks very much

CFMechanics :thumbsup:

I'll try but have some questions. Please post the model numbers of your engine. What test did you do, how did you do them, what were the results of each test. After I read your post I don't think you have a problem with the solenoid, but more likely a bad stator and/or diode. Your numbers will allow me to better picture the wiring and components. I don't know what circuit board you are talking about, maybe we are using different terms, like gas and petro.

Are you getting 12v to the connector in the first picture. If so then you need to change the stator, or the diode if you can find one to replace it.

Its a briggs with the 3/5 charging system. 3 amp to the battery, and 5 amp for the headlights.

[/quote] I don't know what circuit board you are talking about, maybe we are using different terms, like gas and petro.[/QUOTE]

Its a small printed circuit board like an ecu but has about 3-4 glass fuses and about 5 dashboard lights.
I would also say its a 2-4 amp charging circuit on the dc wire with the bump at the connector and the other wire is ac for the lights if fitted.
To check the dc side for battery charging you would normally use a dc shunt but because its below 10 amps you can use a multimeter on its own.
Remove white 2 pin connector. Move your lead from volts to 10 amp slot on meter. Red meter wire to connector wire with bump. black wire to battery live. turn dial to amps dc. should get 2-4 amps dc.
If no reading could be diode so test diode or could be stator. if reading there check wiring to solenoid.
To test ac wire put red meter wire back to volt slot. red meter wire to connector wire without diode.
Black meter wire to battery earth. turn dial to volts ac. should get 28 ish upwards volts.

Sorry for the slow reply.

I have done a test on the power being produced coming from the alternator.

AC Voltage on tick over - 14.0v
AC Voltage full revs - 37.5v


Does this make sense to anyone?

Thanks for the help

What voltage do you have across the battery at full speed? I don't understand what you mean by "tick over" please explain.

Rivets said:

What voltage do you have across the battery at full speed? I don't understand what you mean by "tick over" please explain.

Click to expand...

Tick over means idle like a car pulling up to a junction and stopping. The engine rpm just idles until you drive off and press the accelerator.
Its the british way of explaining how engines run.

Like I posted, battery charge is done by DC amps not AC volts.

"Remove white 2 pin connector. Move your lead from volts to 10 amp slot on meter. Red meter wire to connector wire with bump. black wire to battery live. turn dial to amps dc. should get 2-4 amps dc.
If no reading could be diode so test diode or could be stator. if reading there check wiring to solenoid.
To test ac wire put red meter wire back to volt slot. red meter wire to connector wire without diode.
Black meter wire to battery earth. turn dial to volts ac. should get 28 ish upwards volts"

Now I have learn something today so I can go back to bed. I understand that amps charge the battery, but you can have the required amps (2-4) but if you do not have enough push (volts) the battery will not charge. The way I would tell my students is, think of air and a balloon. You may have enough air in your lungs to fill the balloon, but if you can't blow hard enough the balloon will not fill fully. Sorry I can't get out of teacher mode, after five years.

Yes but you can have all the volts in the world but if no amps it wont charge the battery.
Its a bit like the chicken and the egg. What came first??? The chicken, no the egg, no the chicken!
This is why check your amps first as if no amps then could be low to no volts so you are doing 2 tests in one.
DC shunt is the best and quickest test tool to use.

I agree, but most people on this forum don't have or even know what a DC shunt is or does. They can easily check voltage, which very seldom gives false results and is a great place for them to start.

Rivets said:

I agree, but most people on this forum don't have or even know what a DC shunt is or does. They can easily check voltage, which very seldom gives false results and is a great place for them to start.

Click to expand...

I understand where you are coming from. Its everyone to there own.
When it comes to decorating im crap! :laughing:
Luckily when its only 2 - 4 amp alt they can use their meter and hopefully not blow it up.
When somebody comes on with a problem with a charge problem and the amps is over 10 thats going to be fun!!

Right thanks yet again for the replies.

I have tested the DC Amps and found out that it fluctuates between 3.5 and 3.8 amps.

I take it this is okay then?

I am rewiring the whole tractor now anyway so if there is a problem with the connection to the solenoid it will be sorted out anyway.

cfmechanics said:

Right thanks yet again for the replies.

I have tested the DC Amps and found out that it fluctuates between 3.5 and 3.8 amps.

I take it this is okay then?

I am rewiring the whole tractor now anyway so if there is a problem with the connection to the solenoid it will be sorted out anyway.

Click to expand...

Thats what you are looking for so you know the alt is charging so any issues are with the tractor either wiring or the battery has had it.

pugaltitude said:

Thats what you are looking for so you know the alt is charging so any issues are with the tractor either wiring or the battery has had it.

Click to expand...

I think it is highly likely its the wiring because it is really old and in very poor condition. The battery is almost new so it's unlikely its that.

Thanks for the help! :smile: