Over beers a guy told this tale about his mower dropping to 9v. Alt puts outs 13+v. I just read a thread about pto killing engine but here engine runs fine, pto engages smoothly at wot but the dash volt meter drops to 9v and tractor continues to run until the battery is dead. This just has to be a battery issue, no? I have no more details but I've referred owner here. He's a busy farmer so I'm just trying to help.
#2
StarTech
It is very possible that PTO clutch is partially shorted. I have seen them to draw over 16 amps and still operate. Normally they pull less than 7 amp max with 3-5 amps being the norm.
Check the resistance of the PTO field it should no less than 1.7 ohms.
Also, check the battery with a volt meter when you engage the PTO. I never trust OEM gages. If the battery voltage drops below 10VDC your charging system may not be working properly.
Also check the ground connection to the voltage regulator
If yours it bolted to plastic it needs a good ground connection particularly when drawing heavy current
