Got a Generac 0066720. Runs nice and smooth, but the governor is off. It was surging/hunting, and I adjusted the governor per directions I found on youtube. Loosen nut on governor arm, open throttle to full, gov arm fully in that direction, rotate gov shaft cw. It didn't move much, but now as soon as I take the choke off, it hits full throttle. I can throttle back manually and it runs fine, but the gov just goes to the wall. I'm new to adjusting governor, so I'm sure I did something wrong. This is the video I was going from. I tried adjusting the spring on the gov arm, but I loosened it till it's hanging, and still goes to full throttle.
Lets start over. Loosen the governor arm nut. Move the throttle to full throttle while watching which direction the governor arm moves. And then turn the governor shaft in the same direction as the arm moved. So if the arm moves CW then turn the shaft CW if the shaft went CCW then turn the shaft CCW. And then while holding everything in place tighten the nut. making sure to get it correctly tight so the arm doesn't twist on the shaft.
OK, now you say it was running nice and smooth, but also hunting and surging, Which is it. And how do you know the governor was off. Most generators have one operating speed without a manual throttle control. Do you have a tachometer to properly set the engine speed?
OK, now you say it was running nice and smooth, but also hunting and surging, Which is it. And how do you know the governor was off. Most generators have one operating speed without a manual throttle control. Do you have a tachometer to properly set the engine speed?
I believe that is what I did. When I started, I would start the engine, then turn the knob to the run position, from the start position(which takes off the choke.) The motor would run at what seemed to be a moderate rpm, but would speed up, and slow back down. It would be mostly at that moderate rpm, and then speed up, slow down, pause, then repeat. There is no manual throttle control. I do have a tachometer, but have not put it on this machine. I'll do that tomorrow. When I say it was smooth, it was not missing or sounding rough at all, but the rpm was going up and down. In the last couple of weeks , I've worked on a number of similar sized generators, 4-5kw, single cylinder engines, mostly Briggs. This machine runs smoother than any of them. Of course, all of them were abandoned by their owners. This one had 2 inline fuel filters, and a rusty tank. I bet it sat around with water in the tank till the filters clogged and it wouldn't run any more. The carb looked almost new inside.
Thanks,
Mark
Thanks,
Mark
It was my thought that the hunting, was a symptom of the governor being maladjusted, or not working correctly. I could see that the governor was controlling the throttle. I've worked on small engines for a long time, as a shade tree mechanic, but have not messed with governors much. So much of the time, clean the fuel lines and carb, and you're back in business.
- Joined
- Sep 24, 2017
- Threads
- 265
- Messages
- 6,618
on generators more so, if i get one thats surging, I'll hold the throttle shaft against the stop screw, if it's a governor problem, it will run fine, if it's a fuel problem it will begin running bad or sometimes die all together, 98% of the time surging is a fuel issue
Hold it at idle? That's the only stop screw I know about. I'll try that in the future. I could see the governor tweaking the throttle as it happened, but that could have been a symptom, not the cause I suppose. I gotta get this one back down to reasonable rpm. I'll put the tach on it, and redo the governor adjust and see where I am in the morning.
Like Scrub said. Almost all surging issues are due to fuel/carb issues. I can't think of the last time I ran into a governor surge issue outside of the governor not working and the engine trying to find the self destruct button. Actually I think the last confirmed governor surge I encountered I actually caused on a Briggs V-twin after oil sump gasket replacement, and put too much preload on the static governor setting.
And a tach is important with generators because engine rpm sets the AC frequency.
And a tach is important with generators because engine rpm sets the AC frequency.
So, as advised, I started over. I printed your instructions(which agree with what I'd read elsewhere) and readjusted the governor. Once started, I had to readjust the sole screw/spring, to bring it up from idle. It purrs at 3600 RPM. Due to my background in EE, that means something to me. Thank you Ilengine adn Scrubcadet.
I'm currently seeing 22VAC on one leg, 2VAC on the other. I do have a good AVR from a similar size gen. Am I risking blowing it if I put it on this one?
I'm currently seeing 22VAC on one leg, 2VAC on the other. I do have a good AVR from a similar size gen. Am I risking blowing it if I put it on this one?