shameless 3 #1 Posted December 9, 2011 Hello Wheelhorse Experts! I just aquired a 1988 Wheelhorse 312-8 that would not start. It turned out to be the fuel pump. It now runs but will only idle. I can rev it up at the carb, but the throttle control at the dash does nothing. The control and cable are good and move smoothly. I can see the cable advancing the throttle at the linkage when adjusted at the dash, but it does not increase the rpm. The attched picture is a drawing of the linkage that is attached at the front of the engine at the bottom right side(when looking from the front). The throttle cable is attached at the point shown. the governor spring is not attached at all. The linkage dose not seem to function. The part that the throttle cable attaches to moves independantly from the portion that the governor spring attaches to. It seems that they should move together. The choke linkage is in front of this linkage, it works properly. PLEASE HELP ME OUT, I NEED TO GET THIS WORKING SO I CAN GET THE SNOWTHROWER ATTACHED. Share this post Link to post Share on other sites
rmaynard 16,333 #2 Posted December 9, 2011 :WRS: Are you saying that you don't have the item marked #31 below? Without the spring, there is no connection from the throttle cable to the throttle shaft on the carburetor. Therefore, you won't do anything but idle. Share this post Link to post Share on other sites
shameless 3 #3 Posted December 9, 2011 Hi Maynard: I have all the parts in your diagram. The spring is not connected at the moment. It was connected. The two "ears" of the linkage do not move together as it appears they should. Share this post Link to post Share on other sites
rmaynard 16,333 #4 Posted December 9, 2011 The governor arm #27 is attached to the governor mechanism inside the engine. The linkage rod connects from the top of the arm to the throttle shaft on the carburetor. The spring should attach to either the 2nd or 3rd hole up from the bottom, and attach to the 2nd hole down on item #43. As you move the throttle control on the dash, #43 moves to the right and pulls on the spring #31 which pulls on the arm #27 and opens the throttle on the carburetor. The spring is placed in various hole combinations to adjust for "hunting" and proper control of speed when under load. It's all explained very well in the Kohler service manual. Share this post Link to post Share on other sites
shameless 3 #5 Posted December 9, 2011 Hi Maynard: I think I understand. The linkage has two "ears" kinda looks like a capital L The "ears" move independantly one is in front of the other. the throttle cable on my machine attaches to the lower portion. The governor spring was attached to the upper portion. Should the spring and cable be attached to the same "ear"? Share this post Link to post Share on other sites
rmaynard 16,333 #6 Posted December 9, 2011 Here is a link to the M12 service manual. The quality of the images are pretty bad. I don't own a tractor with the M12 engine, so I hope that another member will chime in and offer some more info for you. http://www.rmaynard.com/M12.pdf Share this post Link to post Share on other sites
shameless 3 #7 Posted December 9, 2011 Thanks Maynard: Thanks for putting my post in the right section. Thanks for the manual. The service manual you show uses a different throttle setup. I will keep hoping someone on the forum has the answer. Thanks again Share this post Link to post Share on other sites
shameless 3 #8 Posted December 9, 2011 A picture is worth a thousand words, or so its said. I took a couple of pics in hopes it would show the problem I have. The first pic , on the left, is with the throttle set at idle (circled in blue) the governor spring attached to top "ear" ( circled in white) The second pic, on the right, is with the throttle fully opened (circled in blue) the governor "ear does not move ( circled in white) This is how the unit came to me. The top "ear" does not move when the throttle position is changed at the dash. Regardless of throttle set position the motor will only idle. I can rev it up at the carb by moving the governor linkage by hand. What is wrong with this setup?? Thanks in advance!! Share this post Link to post Share on other sites
118lfd 8 #9 Posted December 9, 2011 The throttle mechanism (bellcrank)is broken. When the cable pulls the bellcrank down the top part where the spring is attached should move also. Take it apart I bet is either a broken weld or its cracked. It should work like the choke that is in front of it Share this post Link to post Share on other sites
shameless 3 #10 Posted December 10, 2011 Well I got it sorted out! Thanks again Maynard for your prompt reply, putting my original post into the Engines section and the manual. Thanks 118lfd for making me stop and think and figure it out. It turned out to be a broken tack weld. Once apart it was clearly visble where the two parts were originally spot welded. A few light tacks with the mig welder "and the two became one" once again. I did not line it up perfectly but a new bend in the spring and it works awesome. Thanks again! pics of the fix showing the position of the throttle. Like my previous post. the picture on the left is at idle (governor side circled in white and throttle cable side in circled in blue) the picture on the right is wide open throttle ( governor side circled in white and throttle side circled in blue, only slightly visible form behind the choke linkage) I hope this helps anyone with a similar problem! NOW on to modding and old single stage MTD snow thrower to fit this now functioning tractor........ Wish me luck! Share this post Link to post Share on other sites
