deere f725 mower governor

[laurencen]

hi, story had this mower for over 10 years, last year the plastic can gear lost teeth, I replaced the camshaft with the all steel shaft/gear, oil pump gear the governor looked OK put it back together and worked fine, last couple weeks the motor will change RPM for no reason, idle will speed up and just finicky for RPM control requiring minimal throttle to go from idle to full RPM.

tried adjusting the governor lever to the book and no different, there seems to be no rotation on the governor shaft to the linkage that would control the butterfly of the carburetor, the linkage is such that the throttle lever is attached to a plate that rotates, in turn there is a tension spring that goes to the governor lever, that lever at the end is connected to the carburetor butterfly, the operation would indicate the governor lever should have pressure trying to close the butterfly when the throttle is increased its the tension spring doing the pulling on the butterfly to open it further, there is no direct connection mechanical to the throttle and butterfly.

Im thinking the governor gears are stripped, it seized or the weights are stuck, either way its another tear down of the motor, am I missing something on the operation of this governor setuo

thanks

 

[Richard001]

Nope, I think you had diagnosed the problem correctly.

Hind sight is always 20/20. You should have replace the governor assy when you changed the camshaft gear.


Richard

 

[laurencen]

thanks Richard, agree it was a 70 dollar item and chose to not replace not because of cost but it looked fine and no tight spots, at least this time just drain fluids, pull motor and turn upside down to get at it, still a few hours another odd issue, the mechanical fuel pump quit pumping prior to cam gear stripping teeth, figured the pump caused it, since being back in service gone thro 2 pumps and last month installed a electric pump bypassing the mechanical.

guess I will fight it till fall and pull it in the shop

 

[laurencen]

here is a update, we ran the mower with no governor pain yes but cut grass maybe 4 times, finally got the Deere F725 in town and pulled the motor what a mess, the governor assembly gear and weights are disintegrated inside the housing, bits of plastic and metal parts all over, kind of kicking myself as the manual states if the governor is removed replace it, on order with a gasket oil filter and main housing oil seal.

anyone have any insight as to why if you remove the governor off the shaft it needs replacing? it just slides on the shaft as a assembly nothing is loose or was loose anyway, hopefully back to assembling later this week

 

[laurencen]

got it all cleaned up sure missed the disaster as the connecting rods are scored between from debris from governor, after a good clean and wash parts this time are 150 dollars cdn not bad t all, add some oil and antifreeze couple hours to put it back together and see how it runs

 

[laurencen]

got the parts today, Im seeing a odd wear indent on the governor lever where the governor gear would contact it, as the shaft is decent hard steel and the governor pin is plastic no way should this wear like it did, now second guessing did the pin fall off the guide rod on the crank case and the actual governor weights caused this wear? ordered a new shaft today hopefully in tomorrow so assembly on hold for a day or two

 

[Richard001]

Wow, you really got a mess on your hands. Keep the faith, you can do it.
Thanks for letting us know how your work is progressing.

Richard

 

[oldnslo]

I never enjoyed trying to determine what failed first when something blew apart. Did a gear tooth break, then two then three and started galloping which may have over sped the counter weights or jerked them, etc. should I keep the guesses coming?

Either way sounds like you are in the process of correcting all the wrongs you find.

 

[laurencen]

final part arrived and started the assembly, what I notice the governor is tight on its shaft, there is a ring molded into the bore and it pushes over the shaft, once the ring reaches the undercut it spins free and the ring prevents the governor coming off during assembly, this is why if you remove the governor you need to replace as now its free to fall off and Im thinking this is what happened causing the failure, during assembly the gear fell off the shaft and not knowing ran it a couple months before looking into it, fortunately its a few parts and a bit of time but could have ended way worse.

lesson learned, replace the 25 dollar governor every time you split the motor