Battery overcharging

[DHook]

I put in a new battery this morning, replacing the 5 year old original battery. It started acting up a couple weeks ago where it wouldn't start so I jumped it from my battery charger and mowed. Had to do that the last three times I mowed even though I kept the battery on a trickle charger between mows. (Battery disconnected and sitting on the work bench.) Last week, after mowing, I put a volt meter on the battery while it was running at full throttle and showed 15.8 volts. Seems a bit high.

Figuring it just wouldn't hold a charge so I went and bought a new one this morning. Put it in and it started great. Before mowing, I put a meter on the battery while it was running at full throttle and it showed 13.9 (but slowly climbing). (No electric PTO on this mower.) Figured I had it solved. After mowing just now, I put the meter on it again at low throttle and high throttle and got the 15.8 number again.

This seems to be pointing to the voltage regulator. Does that sound correct? From reading other posts, it seems that about 14V is what it should be showing.

It's a B&S 18.5hp. I can post up the number off the valve cover, if that would help.

EDIT: Engine model number from the valve cover: 33r777. 18.5 hp Intek B&S.
Found voltage regulator part number from B&S manual: 794360

Can anyone give me a hint as to where I might locate the voltage regulator on the engine? Or if there even is one?

 

[StarTech]

I would not worry unless it climbs above 16 VDC.

Also need the full engine model including the type number. Right now it appears you have either a dual circuit or tri circuit stator. Dual circuit typically don't use a regulator. And the tri circuit usually has a two wire regulator.

 

[Rivets]

Maybe this manual will be of some help to you. https://www.briggsandstratton.com/c...a/en_us/Files/FAQs/alternator_replacement.pdf

 

[DHook]

Full code off the valve cover:
MODEL: 33R777
TYPE: 0003 G1
CODE: 181102ZD


Thanks for the manual Rivets.

Also, it has climbed above 16v but I've shut it down when it does that because I didn't want to see how high it would get. Fear of blowing up battery or at least cooking it. But I did mow with it when it was overcharging and, when finished, put the volt meter on it while it was still running and it showed 16.2 volts. Haven't seen anything above that yet but not sure it wouldn't keep climbing.

Someone told me to check all the grounds because a bad ground can cause this. I have yet to do this because the weather hasn't been too good around here but will do asap. I did unplug and check a couple of connectors near the starter and they showed no signs of corrosion. Replugged them and checked the Volts again and no change.