18 HP B&S Charging System

[GoHardrGoHome]

I have a 18 HP (M/N 422447 Type 1216 01 Code 90121132) Briggs & Stratton engine on a Grasshopper riding mower with a charging system issue. Note that this stator is the single-wire version. I had to replace the diode in the harness due to damage. Got one from a local B&S dealer that lasted a couple weeks. Went to another more reputable dealer for another...same result. They seem to rectify the AC voltage (~28 vAC) to ~14 vDC current for a short time and then the meter readings are jumping all over the place. I've had it with the diode system! Can someone tell me if I can put a regulator rectifier in the system in place of the diode? If so, what is the P/N for the regulator rectifier? FYI, I ordered from Amazon what I thought would be the correct unit but it is for a 2-wire stator, so I don't think I can make this work without burning something up!

 

[Richard Milhous]

I don't know about this particular system but typically a rectifier includes capacitance to help level the voltage.

 

[slomo]

Can't pull up your engine code. There is a 121602 but no 121601.

 

[GoHardrGoHome]

I suspect that if someone knew the specs of the diode I need, I would put it in and forget about it. B&S lists the diode as part of the stator wiring and doesn't provide the specs on the diode. The dealerships I've dealt with, suspected they were giving me the correct diode. I think not.

 

[GoHardrGoHome]

Can't pull up your engine code. There is a 121602 but no 121601.

Can't pull up your engine code. There is a 121602 but no 121601

Can't pull up your engine code. There is a 121602 but no 121601.

I keep the everything clean. I've recently had the covers off and there was very little debris in there. Code is correct. See attached.

 

[Richard Milhous]

If your tester is reading 28V AC off the stator, your peak voltage is 40V each direction. The diode will have to take that voltage, and whatever peak current the stator can push into the battery - could be pretty large.

 

[GoHardrGoHome]

Agreed! I think I may have already fried a cell in my battery!

 

[slomo]

Great pic. In future posts start with that. We need engine and mower numbers to help.

Still I can't pull it up on the Briggs site.

 

[slomo]

Agreed! I think I may have already fried a cell in my battery!

Take it to an auto parts store. They can load test for free. Make sure it's a load test and not those internal resistance testers.

 

[StarTech]

Great pic. In future posts start with that. We need engine and mower numbers to help.

Still I can't pull it up on the Briggs site.

Must be using the wrong site then because that engine does exist on Power Portal. Keep looking.

or use this link https://www.jackssmallengines.com/j...699999-series/422400-to-422499/422447-1216-01