Cub Cadet S621 w B&S 122602 - Will start but not run

[MowersAreEvil]

Hey everyone, new member here. This forum looks like there are quite a few helpful people here. I am hoping someone will be able to help me with my problem.

Here's what i got. Cub Cadet S621 self propelled mower with a Briggs #122602 motor.

The engine has been running without fail for many years. Now while mowing i ran the motor up against a piece of stiff bamboo sticking out of the ground which struck the carburetor somewhere. The motor slowed down to below an idle and then shut off. Now it will start in what seems to be a very slow idle and stop after a couple of seconds. I suspect it has something to do with the throttle.

Now, I'm pretty good with engines, but without a good diagram of the carburetor linkages, i cannot tell if all of the linkages are still in their proper places. Maybe a spring or linkage was knocked off, but i cannot tell for sure. I have a Briggs parts manual but it is very poor to use for locating parts in their proper locations within the assembly. I will attach a couple of photos and hopefully someone can tell me if all looks proper or if something is missing.

Let me know what y'all think. I gotta get this lawn mowed soon and i know this has to be a simple fix. Thanks in advance for any help you can provide. If anyone has a mower like this please take a close up photo of the same area if possible.

And, No, Mowers are not really evil. Just really mean sometimes.
View attachment 26467View attachment 26468View attachment 26469

 

[ILENGINE]

the arm with the big hole and has the spring attached to it is bent forward and upward. It needs to be brought back down to a parallel position with the rest of the metal, and then pulled back under the piece with the small hole that looks like a throttle cable would hook into. You will need a tachometer to set the speed correctly

 

[MowersAreEvil]

the arm with the big hole and has the spring attached to it is bent forward and upward. It needs to be brought back down to a parallel position with the rest of the metal, and then pulled back under the piece with the small hole that looks like a throttle cable would hook into. You will need a tachometer to set the speed correctly

Thanks for your response.

So you're saying that nothing is missing, just that the arm is bent out of shape?

Look at the throttle valve arm below that arm. Is there supposed to be another spring attached to that? Or is the upper arm and spring used to keep the throttle open while the governor link is pulling against that?

Thanks again.

 

[ILENGINE]

Spring keeps the throttle open and the governor links tries to close it. I don't see anything missing. I actually went and looked at an engine in my boneyard to compare what you have to what it should look like. I knew something was bent but just couldn't articulate how it was actually out of place.

 

[MowersAreEvil]

Spring keeps the throttle open and the governor links tries to close it. I don't see anything missing. I actually went and looked at an engine in my boneyard to compare what you have to what it should look like. I knew something was bent but just couldn't articulate how it was actually out of place.

Well thanks a bunch, IlEngine. I think that may have helped a lot. See the new attached image where i have circled the area you mentioned. Now that you mentioned it, i compared my photos closely with this image and can now see how the tab with the large hole should be bent so that it lies over the tab with the small hole. I did try moving the spring to the small hole and it did run properly. Now that i know how this works, I feel comfortable bending the big holed tab until it makes the engine run at the proper RPM. If you get a chance, take a photo of the one in your boneyard and upload it. But its no biggie now.

Thanks a bunch again and now i can mow the yard so my neighbors don't think I've been dead in my house for 3 weeks. :laughing: