ok i have good voltage from the switch to the pto connector and good voltage going from the pto connector to the pto. still not working. looks like i'm going to replace the oil seal down there as everything is wet with oil. i'm going to try the bolt and steel pin way to get that pto and pully assembly off. i read about it on here and if anybody has done it this way lately and has any more advice i'll be happy to here it. also how hard is it to remove the motor as i'll have to do this to fix the oil seal? all testing was made with me on the seat. can these pto's be inspected and rebuilt? thanks, Denny
Mine was easy to remove, but that's a 3600 with a horizontal crank - easier to get at and not in the path of leaking oil. It sounds like you've already checked this forum and seen that you need a good voltage to operate the pto - a marginal battery or charging system could fail to engage the pto. The sudden failure you described might be electrical (as opposed to debris or adjustment). This Scag manual www.ganos.com/electricclutchtesting.pdf has testing for a similar Ogura pto clutch. If the electrics are OK I'd disassemble it, and if anything is broken in there it should be obvious. It could probably use a good cleaning anyway.
thanks for the reply Wayne. yes it looks like i'll have to remove the engine somewhat to get at the pto. i disconnected the switch to pto plug and measured 12 something from the switch and 12 something going to the pto but no action of the pto engaging. it's also pretty wet around the pto and pulleys. i'll try to get the pto off this week with a method shown on this website. i have been the repair man on all my lawn tractors since the 70's, but have never worked on a Yamaha. i just like this mower. i have a Troybuilt mower being delivered wednesday so i will not be pressed for time for the remainder of the season. i don't like to get behind on my mowing. i even tried to jump the pto without success and yes i was sitting on the seat. i'll try to keep everybody posted on this project. Denny