1988 Canadiantire craftsman 11 hp Briggs over charges,but has no regulator?

[warren]

I just bought this driving lawn tractor engine#253707-0419-0419-01 Code#88102551 downloaded the electrical schematic and it shows NO Reg.Cheaked and no Reg.
Problem is volts on battery will runn up to 16.7 DC and 15.7 at idle.I have adjusted govener low as it goes and lil change.I tested Diode /Rec and its working correctly,ohms only one way(upstream).Tested VDC upstream of Diode and got 28 VDC. Tested red wire from white plug down stream of Diode and get 12.9DCV to 13.9 DCV.Cheaked ground from battery good,clean and tight. I am stumped! I am using my snowmobile battery which is good,sealed unit with 235 CCA.
Battery shows 12.8 with mower off. Pulled flywheel cleaned and checked magnets and stator/Alt also installed new plug and regapped coil,no change.Any ideas.
If i unhook plug to stator/Alt battery will still start mower and does show a drop off 1 volt when crancking,but obviously will not charge if wire to stator/Alt no hooked up.Plug also has a wire for headlights and works ACV only.Thx warren

 

[warren]

I just bought this driving lawn tractor engine#253707-0419-0419-01 Code#88102551 downloaded the electrical schematic and it shows NO Reg.Cheaked and no Reg.
Problem is volts on battery will runn up to 16.7 DC and 15.7 at idle.I have adjusted govener low as it goes and lil change.I tested Diode /Rec and its working correctly,ohms only one way(upstream).Tested VDC upstream of Diode and got 28 VDC. Tested red wire from white plug down stream of Diode and get 12.9DCV to 13.9 DCV.Cheaked ground from battery good,clean and tight. I am stumped! I am using my snowmobile battery which is good,sealed unit with 235 CCA.
Battery shows 12.8 with mower off. Pulled flywheel cleaned and checked magnets and stator/Alt also installed new plug and regapped coil,no change.Any ideas.
If i unhook plug to stator/Alt battery will still start mower and does show a drop off 1 volt when crancking,but obviously will not charge if wire to stator/Alt no hooked up.Plug also has a wire for headlights and works ACV only.Thx warren

Wow,no replys and almost 130 views.Question is there another way to reduce volts to battery if mower is a 2 circuit system and does not have a come with a regulator.The really confusing part is the red wire coming from the Altenator shows under 14 volts DCV at the plug but somehow at the battery is shows 16.7 after approx 15 min running.It will start off around 12.8 at battery and gradually climb up to 16.7.Again the Diode is working correctly,what am i missing.Even if your not sure throw something at me .thx

 

[bertsmobile1]

Well that is because you are alone you are very alone, but i would rush out and patient that engine that creates more electricity than it generates.
The first question is .
Is this a problem ?
What caused you to take all of these readings ?
What is the mower doing ?

Now if it relly is bugging you you can fit a 12V Zenner diode and heat sink.
This will limit the maximum voltage to 15 V and dump any thing higher as heat.

Voltage regulators cost money around $ 40 wholesale where as a diode is about 5｢.
The bottom end of domestic mowers is very price sensitive so they get single diodes rather than full wave rectifiers and no regulation.
Most only get used for an hour or two 20 to 30 times a year and they use the battery to regulater the voltage as the only thing voltage is used for is the starter motor, clutch & hour meter.
Also remember it is not a constant voltage it is peak voltage your meter is reading.
What your battery sees is 0V rising to 16.7 then dropping back to 0 in little power pulses.

 

[warren]

Well that is because you are alone you are very alone, but i would rush out and patient that engine that creates more electricity than it generates.
The first question is .
Is this a problem ?
What caused you to take all of these readings ?
What is the mower doing ?

Now if it relly is bugging you you can fit a 12V Zenner diode and heat sink.
This will limit the maximum voltage to 15 V and dump any thing higher as heat.

Voltage regulators cost money around $ 40 wholesale where as a diode is about 5｢.
The bottom end of domestic mowers is very price sensitive so they get single diodes rather than full wave rectifiers and no regulation.
Most only get used for an hour or two 20 to 30 times a year and they use the battery to regulater the voltage as the only thing voltage is used for is the starter motor, clutch & hour meter.
Also remember it is not a constant voltage it is peak voltage your meter is reading.
What your battery sees is 0V rising to 16.7 then dropping back to 0 in little power pulses.

Firstly thx for reply,not sure i understand ,reason i tested the battery was i just replaced the motor ,had a rod go thru side,so found a 12 hp same vintage and pulled my carb,flywheel,stator ect to keep everything the same.I cheaked battery to make sure everything was workin rite and chargeing,thats when i noticed the high voltage,really don,t want to ruin a perfectly good new battery and boil it dry or worse blow it up if thats possible.I always assumed u want the voltage to be somewere between 12.2 and 14.7.So replacing the Current Diode with a Zenner Diode will help? Please explain heat sink .Thx

 

[bertsmobile1]

Firstly thx for reply,not sure i understand ,reason i tested the battery was i just replaced the motor ,had a rod go thru side,so found a 12 hp same vintage and pulled my carb,flywheel,stator ect to keep everything the same.I cheaked battery to make sure everything was workin rite and chargeing,thats when i noticed the high voltage,really don,t want to ruin a perfectly good new battery and boil it dry or worse blow it up if thats possible.I always assumed u want the voltage to be somewere between 12.2 and 14.7.So replacing the Current Diode with a Zenner Diode will help? Please explain heat sink .Thx

I think you are over thinking the situation and it will most likely be fine as is.

However if you want to limit the volage you can fit a Zenner.
It goes in line after the regular diode and is used on a lot of Pommie motorcycles of the 50's & 60's because it is cheap

Now your mower will not cause the battery to blow up & I don't think you have any problem.

 

[warren]

I think you are over thinking the situation and it will most likely be fine as is.

However if you want to limit the volage you can fit a Zenner.
It goes in line after the regular diode and is used on a lot of Pommie motorcycles of the 50's & 60's because it is cheap

Now your mower will not cause the battery to blow up & I don't think you have any problem.

Thx maybe what i failed to mention is the battery voltage when at full throttle will creep up BUT STAY at 16.7 VDC,it does not flutuate,if that matters.
I looked at the 12 volt Zenner Diodes and there r many options and wattages,will they all work the same or is there a specific one that will drop me
approx 3 volts, also u stated the zenner is installed after the regular diode ,is that up or down stream of the currect diode/rec ( stator side or plug side) ,Also is there different ends on the zenner ,does it matter which way i connect it ,thx Sorry electrical not my strong suit!