# Generac 3500 (model 1313) with GN 190 auto idle



## mjadams51 (Sep 27, 2006)

Hey all, 
My Generac 3500 generator with GN-190 is running fine and she generates electricity enough to run power tools and even my Dyson Animal vacuum cleaner, but I think her auto idle function is not working too well.

Background: the unit has a button under the 15 amp service (two grounded outlets) that keeps the engine at a low idle when not under load. She's idling high no matter the load, and only surges a little when I give her close to a maximum load. I pulled the carb recently to clean it out (it sat for a long time without running). I've also replaced the air pre-filter and filter with new ones. She's not running rough, lean or rich, but the change in idle is minimal (not like when she was new). I've tried the idle adjustment screw, no joy. 

Because she does change RPM a little, I think the feature is working, just not correctly. Anyone have any experience with this?

Thanks.


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## tom tilson (May 1, 2006)

I can help, but running out of tme this am. Will get back with you in the afternoon. Forget about working on the carb, the trouble is else where unless you just have a sticking throttle plate. Check it by moving the lever at the carb and checking it for a bind


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## tom tilson (May 1, 2006)

You may have an electric control problem or/and a mechanical one. 
Take the easiest first: You have been into the carb right? You should have noticed an electric solenoid mounted vertically on the carb with an adjustment nut on top. With the engine running observe the solenoid plunger and see if the moveable slug moves while switching the auto idle sw back and forth. The no-load idle with auto control switch off should be 3690-3810 rpm with the auto cont on speed should drop to around 2700 rpm(40/45 Hz). Can you borrow a tach or 120v plug into receptale frequency meter? With auto control on and no elec load, loosen jam nut and turn adjustment CCW and adjust to specified speed.( Do this only if you know the solenoid is moving up and down with a flip of the sw).This adjustment adds or removes tension on governor spring.

If the solenoid is not moving per above instructions, check it out electrically. Remove control panel cover and look for the control card. should be about three to four or maybe larger inches. Card has three wire connection posts on bottom edge and a five pin connector on the left side. With unit running and switch in auto idle there should be 115-to135 or so volts AC across pins (counting one two three across bottm from left to right ) two and three. without changing anything, check for around 120 vdc across the two black wires. These feed the carb solenoid If neither of the above cahges any thing, the solenoid coil may have an open in the winding or mechanically hung up. Chk it out. I hope that I have not made this more complicated than it really is. Part of my enjoyment is helping people so do not hesitate to converse with me as much as you need too. Tom [email protected]


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## mjadams51 (Sep 27, 2006)

*Thanks for the advice*

Tom, I will look at the carb as you have instructed, and if that does not help then I'll dive into the control panel and have a look see.

Thanks very much for your advice! I'll let you know how it goes.

Mark


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