# Help with Governor Linkage - Tecumseh Over Revving



## rod330 (Oct 9, 2015)

I'm refurbishing an Ariens ST7524E (932041) with a Tecumseh OH195SP engine. It starts fine with a new carb and runs well at idle (around 1800- 1900 RPM). However, it over revs at full throttle and I immediately shut if off when it jumped to 4400 RPM. I worked on a similar machine a couple of years ago but didn't have this issue. 

I don't see any way to adjust the governor arm and there isn't an adjustment screw at the throttle linkage attached to the engine shroud...at least not that I can see. At first I thought I could adjust the arm with screw at the bottom but it appears that's just how the arm is attached to the oblong engine governor shaft.

There really isn't much throttle travel on this model....it's more like off / idle / and full throttle. The yellow snot in the 4th photo is Fluid Film I used to lubricate the throttle mechanism. Looking at the parts diagram I see there's a spring (#19A) but I'm not finding it on my unit...not sure it's intended for the governor linkage though. Any suggestions would be appreciated.


----------



## rod330 (Oct 9, 2015)

Well, now that I expand the first and second photos, I'm thinking the governor arm can indeed be adjusted at the shaft near the screw. The end of the engine governor shaft is oblong (maybe to hold while you move the arm?) but the shaft itself appears to be round....hmmm....


----------



## toromike (Aug 20, 2018)

DO NOT adjust the governor arm at the shaft near the screw. 
Note the spring that goes from the governor arm to the tab that hangs down from the throttle control, the spring wire goes through the hole in the tab and then forms a U. The tab that hangs down is the high speed adjustment, bend the tab to adjust the maximum speed.


----------



## rod330 (Oct 9, 2015)

toromike said:


> DO NOT adjust the governor arm at the shaft near the screw.
> Note the spring that goes from the governor arm to the tab that hangs down from the throttle control, the spring wire goes through the hole in the tab and then forms a U. The tab that hangs down is the high speed adjustment, bend the tab to adjust the maximum speed.


Excellent - the tab at the RED arrow, correct? 
Thanks Toromike!


----------



## toromike (Aug 20, 2018)

Correct, the red arrow tab is the governed high speed adjustment. I think this engine has a governed idle speed as well, the green arrow tab would be the governed idle speed adjustment. 

FYI, do not move the governor arm at the shaft near the screw unless you are disassembling the governor, or resetting the governor adjustment. There is a specific procedure to reset the governor arm, but it rarely needs to be done, mostly when someone has messed with it.


----------



## rod330 (Oct 9, 2015)

toromike said:


> There is a specific procedure to reset the governor arm, but it rarely needs to be done, mostly when someone has messed with it.


As it turns out, someone messed with it (me) before reading your first post. Dang it!! Is there a source document I can reference instead of continuing to pester you? :smile2:


----------



## toromike (Aug 20, 2018)

rod330 said:


> As it turns out, someone messed with it (me) before reading your first post. Dang it!!


Don't worry about it, we've all done it at one time or another. 

All these governors work on the same principle. These videos explain how to do it, they may not be exactly like your machine but the principle is the same. If you need more I can come up with something else.


----------



## toromike (Aug 20, 2018)

rod330, here are some Tecumseh manuals that will give you further information on governors. They also contain lots of other information.

see page 26 figure 14 for a diagram of your throttle speed control
see page 25 at the bottom for how to set idle and high speeds
http://www.barrettsmallengine.com/manual/tecumsehoverheadvalvemanual.pdf

see page 27 for how to reset the governor arm, 
I think the videos explain it better
http://www.barrettsmallengine.com/manual/tecumsehlheadmanual.pdf

Also, lots of other tecumseh manuals are available here
Tecumseh Service Manuals

Good luck


----------



## rod330 (Oct 9, 2015)

Thanks again, Toromike.
Yes, the 2nd Teryl video is especially good and I hadn't seen that one. 
Those tech manuals are quite good; I glanced at two of them before posting but wasn't as diligent as you at sifting through the many varieties. I'll be more patient next time :smile2:

Anyway, I'm going to take a crack at it Friday, weather permitting. It should be easy to get full throttle RPM to 3600 bending the tab.


----------



## orangputeh (Nov 24, 2016)

just wondering if throttle plate moves freely? had this problem on several Honda hs724's and the throttle plate was stuck open. a little oil and they worked fine and had no more problems. 

however in these cases it over revved from the beginning.


----------



## rod330 (Oct 9, 2015)

orangputeh said:


> just wondering if throttle plate moves freely? had this problem on several Honda hs724's and the throttle plate was stuck open. a little oil and they worked fine and had no more problems.
> 
> however in these cases it over revved from the beginning.


Yep, I'd normally check the throttle butterfly movement too but I installed a brand new carb. The prior owner worked on the old carb (who knows what else) so I bought it as a non-running machine. I'm near the end of my patience rebuilding carbs when the old gas in the tank smells like cat pee and the Amazon folks put a new one on the front porch in two days for $12. Here's a photo of the last carb I worked on a couple of weeks ago...wasted nearly an entire day fussing with something that looked like it was running on motor oil :crying:


----------



## Oneacer (Jan 3, 2011)

@rod,

Yeah, I just order a new one at those prices from Amazon as well … not even worth the time or aggravation to break down a clogged one.

I have a box of old ones, and will break them down and clean them come summer, if I am bored on a nice afternoon …  … maybe ….


----------



## rod330 (Oct 9, 2015)

Toromike, I just wanted to thank you again.
It took less than 10 minutes to get that governor perfectly dialed in. I finished up the remaining items on my checklist and the 7524 is better than new.


----------



## toromike (Aug 20, 2018)

Hi Rod330. I'm glad to hear that you got it sorted out. That's a good looking machine. Now all we need is some snow, still nothing in Maryland. Thanks for letting us know the outcome. Happy Holidays.


----------

