Runaway governor on K321 Kohler engine

[BOBTHEBOPPER 3]

I have a kohler K321 with a runaway governor situation. The engine ran wild, had to shut it down el pronto. Checked the governor linkage (tight to cross shaft ). All linkages and springs OK. Ran engine with carb disconnected (held in idle position) from gov linkage. While running rotated gov cross shaft back and forth, no resistance from gov system. Removed spacer from cross shaft and ran again rotating cross shaft with slight in and out movement, still no contact with governor. Dismantled engine, checked cross shaft (all OK, Tang tight to cross shaft, bearing good). Governor gear teeth not worn, weights good no slop, weight rivets good, gov gear bore egg shaped about .005. Cam shaft gear teeth not worn and shaft pin good. Replaced gov gear with one from another good running engine. Reassembled engine and same problem exists.  "Help"

Edited October 7, 2016 by BOBTHEBOPPER
Missed ending

[Mike'sHorseBarn 2,625]

I'm embarrassed to admit this, but I had this problem with a briggs once. I had the engine all apart, replaced the governor gear and everything, put the engine back together and still the same problem. So i just happened to look in the carb and the flapper (what i call it anyway) was gone! The screws came out and and it got sucked into the intake valve! That's why it only ran wide open! Just saying it could be something that simple. 

[BOBTHEBOPPER 3]

Thanks Mike, but this is not the case. I need someone who has a K series engine who has had or has experienced this problem.     

 

BOBTHEBOPPER

[oldredrider 2,547]

I had exactly the same issue as you on a K-321. Tore the engine down and found the piston skirt exploded and took out some teeth on the governor gear. Put it back together with all new parts and worked fine.

What occurred to me on reassembley, was it had no rev limiter. I've seen this on other K-321 engines since then. I installed one and haven't had a problem since. Something to check since all your other options have been covered. 

[BOBTHEBOPPER 3]

Thanks oldredrider

      I had to tear the engine down to see what could be causing "no governor control" and as stated all parts OK (piston, cam gear teeth and governor teeth etc. except for governor gear bore worn about .005 egg shaped). I can;t find any cause for the problem. What is the rev limiter? I have the kohler service manual for the K series  engines and don't see anything  listed (or parts referring}  to "rev limiter". I guess will have to pull the welch plug for the governor gear shaft so I can see whats UP. There is nothing else left to investigate. Any other suggestions please keep them comming.     

 

BOBTHEBOPPER

[Elkskin's mower junkyard 1,117]

4 hours ago, BOBTHEBOPPER said:

Thanks oldredrider

      I had to tear the engine down to see what could be causing "no governor control" and as stated all parts OK (piston, cam gear teeth and governor teeth etc. except for governor gear bore worn about .005 egg shaped). I can;t find any cause for the problem. What is the rev limiter? I have the kohler service manual for the K series  engines and don't see anything  listed (or parts referring}  to "rev limiter". I guess will have to pull the welch plug for the governor gear shaft so I can see whats UP. There is nothing else left to investigate. Any other suggestions please keep them comming.     

 

BOBTHEBOPPER

i think he ment by rev limiter being the governor itself. i havent had this happen on a akohler but i did have it happen on a cast iron briggs but it wasnt running wide open had no power and rpms wondered all over. what happen was rust formed on governor affecting the weights not throwing them out far enough. i replaced governor and fixed that issue. are you setting governor right? i am not sure on bigger k series but i know on 7s and 8s you adjust the governor holding carb wide open and turning shaft counterclockwise

Edited October 11, 2016 by craftsmanmowerfreak

[Mike'sHorseBarn 2,625]

Yea I agree with craftsmanmowerfreak. If all the necessary parts look good then we should reset it to factory setting. If that doesn't work then there has got to be something broken. If all internals look good and you replaced the existing governor gear with one from a working engine then it has to be the cross shaft. I know you said it looks good, but I don't know what else it could be. I have attached the adjustment procedures below and a picture of the working governor from the Kohler manual.

 

  

 

Here is the Kohler manual as well if you think it would help. 

 

 

[gwest_ca-(File Mod) 10,488]

If you follow the Kohler instructions like I do you will get it wrong and I don't understand why. Their clockwise and counter-clockwise are different than mine.

 

With the engine not running -

Move the carb throttle from the idle position to wide open throttle.

As you do this make note of which way the governor cross shaft turns when going from the idle position to wide open throttle. Clockwise or counter-clockwise.

Loosen the governor arm clamp enough so the shaft will rotate in the arm.

Move the carb throttle to the wide open position and hold it there with your 3rd hand or an elastic band.

Now rotate the governor cross shaft clockwise or counter-clockwise as noted before as far as it will go with light pressure.

Tighten the clamp on the governor arm.

Let go of the carb throttle.

Start engine and see if it works.

 

A governor tries to lower the rpm using a force varied by engine rpm.

The throttle cable pulls on the governor spring to increase rpm.

The balance of these two forces is the rpm you end up with.

 

Garry

[BOBTHEBOPPER 3]

Gary,   Thanks for your reply. Look at the reply from Mikes Horse Barn.  This is the governor arrangement for all the K series Kohler engines. It is from the Kohler service manual. The governor shown is in the static position (engine not running) as is pictured. The cross shaft is then turned from right to left (counter clockwise) placing the governor tang in contact with the governor gear thrust button. While holding the cross shaft in this position rotate the governor arm also counter clockwise (right to lefthe idle position. t as far as possible). Tighten the governor arm bolt and nut.  This places the carb in the "wide open position" in the static mode. When the engine is started the  governor gear thrust button extends (due to the governor gear weights outward thrust) and rotates the goverenor arm in the "clockwise" direction thus closing the carb throttle. As stated in my initial question I ran the engine with no governor arm connected to the cross shaft an blocked the carb in the idle position. With the engine running I held the cross shaft with my fingers and no contact could be felt with the governor gear. I turned it both ways and moved it in and out. No contact was felt. Also note that the governor cross shaft "cannot" be installed upside down (with tang pointing up).  Still lost as to what is happening. Iwill have to remove the welch plug for the governor and see if the tang is contacting the governor gear thrust button.

 

Any other help would be appreciated.

 

BOBTHEBOPPER 

[WH nut 553]

Pull it a part and make sure the snap ring didn't come off of the governor gear, and make sure the throw weights are working properly. I had one loose the snap ring and went into the rod and chewed things up.

[BOBTHEBOPPER 3]

WH nut,

 Thanks for your reply, but I am not sure you are talking about a Kohler K series engine. Any K series I have worked on (and in the Kohler service manual) does not show or have a snap ring on the governor gear. Maybe it's pre K series?

 

BOBTHEBOPPER

[WH nut 553]

3 hours ago, BOBTHEBOPPER said:

WH nut,

 Thanks for your reply, but I am not sure you are talking about a Kohler K series engine. Any K series I have worked on (and in the Kohler service manual) does not show or have a snap ring on the governor gear. Maybe it's pre K series?

 

BOBTHEBOPPER

I  miss spoke, I meant the roll pin on the flyweight

 

[BOBTHEBOPPER 3]

WH nut,

 

   OK. The roll pins are OK.  Still need "help".

 

BOBTHEBOPPER

[new2horses 287]

On ‎10‎/‎11‎/‎2016 at 7:50 AM, Mike'sHorseBarn said:

Yea I agree with craftsmanmowerfreak. If all the necessary parts look good then we should reset it to factory setting. If that doesn't work then there has got to be something broken. If all internals look good and you replaced the existing governor gear with one from a working engine then it has to be the cross shaft. I know you said it looks good, but I don't know what else it could be. I have attached the adjustment procedures below and a picture of the working governor from the Kohler manual.

 

  

 

Here is the Kohler manual as well if you think it would help. 

 

 

If these instructions are followed correctly the governor, if it doesn't have any broken parts, will work as intended.

An easy way to think about setting the governor is as follows, move the throttle lever to the wide open position, the governor arm will be rotated counterclockwise away from the carburetor, loosen the  nut on the clamp bolt and with a pair of pliers (like shown in the picture) rotate the governor cross-shaft counterclockwise as far as it will go. Tighten the clamp bolt and you're finished.

[BOBTHEBOPPER 3]

HI guys, The adjustment is not the problem, all is OK. Does anyone have any sugestions? I will pull the welch plug and repost.

[123GO 78]

What was the problem here btw? Was is simply too painful to talk about  or too embarrassing to admit ? 

[richmondred01 2,202]

Double check the tab on the cross shaft. Affirm that it’s pushing the the plunger on the governor assembly gear.

 

Edited July 20, 2019 by richmondred01

[BOBTHEBOPPER 3]

Hi richmondred01, thanks for your suggestion however the problem was solved. I stated this in a post in 2017 however it does not appear to be there now and was either removed or somehow lost. This post should apply too 123GO as well as in trying to answer his post I was not able to submit. I guess 123GO was partially correct as far as embarrassing to admit however I had posted the solution. To be brief the problem was that the arm is attached to the cross shaft with a shoulder bolt. The nut was tightened down and I checked to see if the arm was tight on the cross shaft with my fingers (my mistake). IT felt tight however there were not enough threads on the shoulder bolt to fully tighten down and to prevent the arm from "FIRMLY" tightening to the cross shaft. I replaced the bolt with a fully threaded bolt and lock nut. Problem solved. 

[richmondred01 2,202]

Perfect. Glad the issue was resolved.

 

I didn’t realize it was an old thread. Now I’m embarrassed.

[123GO 78]

 Sorry' didn't mean to stir things up here..lol

 I was reading through here as a friend's 12hp Kohler was doing it too after he removed his carb & cleaned it.  I had assumed you had it figured out by now BOBTHEBOPPER or set it to be usable one, but' guess what?

   This 12hp had the same problem and yep' a fully threaded bolt fixed it, so I Thank You!!    2 sets of "old" eyes' failed us from seeing the nut was bottoming out on the shank before actually tightening.

 

  btw:

"Never" be imbarased on here anytime, we all have our walk of shame moments.

Take care!

[BOBTHEBOPPER 3]

Hi  123GO, Just an addition to my earlier post, I have a few other K series engines which have been worked on over the years and I have noticed that the arm clamp has a tendency to stretch open each time it is removed and replaced from the cross shaft. I believe that the original bolt that they used was a partially threaded (or shoulder bolt) and this was to prevent over tightening the arm. I have noticed if the arm clamp is over tightened it will distort. The idea was fine to prevent distortion as long as it is not losened and tightened to many times and thus result in slipping on the cross shaft..

BOBTHEBOPPER

[123GO 78]

Thanks BOBTHEBOPPER,

Yes' I first saw this scenario happen on motorcycle brake arms before disc brakes came out on them. 

  We made sure to only snug it tight here so not to bend it because you're correct overtightening it will deform these arms long before a bolt/nut strips out.

 Agree a shoulder bolt with a solid shank is best used here if one will still work to prevent it from happening.

 Thanks again!

Edited July 23, 2019 by 123GO

[wh315-8 439]

               I know this is an old post but it helped me and wanted to share my issue that led to this and hope this info can help someone else with similar issues. I had bought an 856 with K181. PO said he couldn't get it to run. When I got her home and power washed it I discovered all 4 block to pan bolts were loose and 2 were practically out completely.  Figured at this point it was a rebuild. But it had oil still so figured I might be safe, so I changed oil adjusted points and plug got spark and It was running but not at slow idle, would idle down put not as low as it should without shutting down. (at this point I did a small dozer job pushing dirt around) Turned out it had a blown head gasket. Sanded down the head with wet sandpaper on a pane of glass and replaced gasket. This gave me great compression as could be expected. Than it was running rough so I rebuilt the carb and the fuel pump (they needed it). After this it wouldn't idle but run fast, rechecked governor adjustment and fuel bowl clearance, checked the condenser, coil and replaced starter switch and added a solenoid. So all electrical tested out still no slow idle and only fast. I was at wits end because she ran decent with a blown head gasket and dirty fuel pump. Researched possible problems and everything tested out to the good.

               I finally thought it thru and figured it must be a stuck governor. I have rebuilt a few K engines and one I had torn down had just that stuck flyweights on governor. But it still puzzled me how could it have run before I did all the work mentioned above. (and remember  when I did I was pushing dirt with dozer blade and it did a good job). So before I tore into the engine I researched 'Kohler K engine governor troubleshooting', and it led me to this posting. As I read I thought I know that my governor arm is tight because when I move the arm the shaft turns with it. I had checked this setting many times throughout this process. Couldn't wait to get home from work and try to turn the shaft with pliers. Ah Ha moment has arrived. I could turn the shaft with pliers even thou the arm was tight. The bolt had plenty of thread but the collapse had no gap. I than took the arm off and filed the collapse only a little on each side, put it back together and started her and she runs like a champ. Lesson learned is to check the shaft with pliers after the bolt is tightened. What I realized is, when the engine is off and no pressure on the governor shaft the arm will turn it. Once the governor is pushing on the tab to rotate shaft it is too much pressure to turn the arm.

[BOBTHEBOPPER 3]

Thanks for the feedback wh315-8, I am glad I was able to help you and others. Lets keep these old K-series running and keep the old well engineered USA made items from extinction.

BOBTHEBOPPER.