beuce Posted October 28, 2003 Posted October 28, 2003 I have a Sovereign 3012 w/a 12 hp Briggs which I am having some problems with. The springs on the govenor pull the govenor up and in turn set the throttle to full speed. This doesn't seem right to me. The machine will start and idle fine if I hold the throttle closed at the carb, but as soon as I let it go it springs to full throttle again and the engine sputters. Anyone have insight on what I may be doing wrong? Thanks Brian
rjgoth Posted October 28, 2003 Posted October 28, 2003 Ill take a shot at this -- please correct me if I state incorrectly. When you start the engine, the govenor springs should hold the throttle valve full open. Once the engine starts the counterweights on the govenor should pull the throttle back down to idle if that is where your throttle setting is on the dash. This is how it is supposed to work. In your case I would double check the spring settings on the govenor arm, as well as their placement. There is a link on this site that is a parts manual for the 12 hp briggs, you can use that as a source to check this. Double check to see if the linkages are all moving freely, it seems as thought the linkage is stuck in the full open position, and the spring is holding it to full throttle. Somethign in the linkage or springs is holding that throttle open all the way. I hope this helps. I do have a 12 engine at home that I can double check the linkage for you tonight too. Good luck, Ryan
beuce Posted October 28, 2003 Author Posted October 28, 2003 I did find the link and set the springs as shown a couple days ago. I think all the linkages are moving freely. I can manualy push down the govenor arm as well as close the throttle. The govenor just springs right back up as soon as I let go though. Could the governor be broke inside the engine? If I were to disconnect the govenor and start the engine could I see if the counterweights are pulling the arm down, maybe even feel it pushing down? I am so clueless when it comes to this govenor thing. Thanks again!
rjgoth Posted October 28, 2003 Posted October 28, 2003 You may be onto something with the idea of the counter-weights not to be functioning properly inside the engine, that could explain why the engine goes to full throttle. This could also happen if the springs are too tight and the counter-weights are not able to pull hard enough to counteract the spring force. Those would be my diagnosis. Let me know if you find anything else. I hope that helped you get some sort of direction. Ryan
PatRarick Posted October 29, 2003 Posted October 29, 2003 First, what have you done with the carb or throttle? It's possible that you have the wrong carburetor. The carburetors on the aluminum block engines and the carburetors on the cast iron engines are identical EXCEPT for the throttle shaft. The throttles work exactly opposite. If you have an aluminum block carb on your engine, the governer would act to slow the engine down, but would actually be opening the throttle. To check, push the governer arm UP. The throttle stop on the throttle shaft should hit the throttle stop of the carb body. If the idle speed screw hits the throttle stop on the carb body, you have the wrong carb, throttle shaft, OR a new throttle shaft was incorrectly installed. This is easily rectified, but I won't go into that unless that appears to be your problem. If you have the correct carb, have you performed the static adjustment on the governer? Loosen the governer arm clamp bolt. Push the governer arm UP, which should put the throttle in wide open position. While holding in that position, use a screwdriver and turn the governer shaft fully COUNTERCLOCKWISE. Tighten the governer arm clamp bolt. Pat
beuce Posted October 29, 2003 Author Posted October 29, 2003 Well it was way too cold to work on it last night, but it does seem like there is a lot of spring tension on the arm. Maybe someone installed the wrong springs or something. I believe I do have the right carb, when I push up on the arm it goes to full throttle on the carb, when pushed down it hits the idle screw. I did do the static adujustment on the govenor. Everything seems to be moving freely. This machine came with a house I just purchased, so I am very new to this. The previous owner couldn't get it running, but I was able to get it to run with a little points adjustment, new plug, and plug boot. I am hoping to get this running decent before winter so I can plow some snow! Thanks to all that replied!!!
PatRarick Posted October 29, 2003 Posted October 29, 2003 OK. Something else in you original post just caught me. You said that it sputters when it is at full throttle. You could have weak or intermittant spark which is keeping the engine from reaching enough rpm's to pull the governer down. Purchase an inline spark tester. It's a handy, inexpensive tool to have. Observe the spark while the engine is running. Bad spark plug, points, condenser, armature (coil), a short in an ignition wire or a bad ignition switch can all allow the engine to run at idle, but have intermitant spark when engine speed increases, even if that speed increases only slightly. If you can't find a spark tester, I would start by replacing the points and condenser. Pat
rjgoth Posted October 29, 2003 Posted October 29, 2003 Let us know how things work out with this engine and the govenor situation. Perhaps you could get the part number of the correct springs for your engine and install them, if anything it will eliminate or isolate the problem more so than it is right now. I think the springs are pretty cheap too. Just a thought. Ryan
beuce Posted October 29, 2003 Author Posted October 29, 2003 I think I am going to go with the weak spark thing. I noticed that it sparks well MOST of the time, but others not so well. I was passing the blame on the plug getting dirty. I have a feeling the coil may be bad, the plug wire doesn't look to healthy either. It does have new points and condensor though. How hard is it replace the coil? I have seen in the past where people have switched to electronic or have used an external coil? Or should I just replace the original. I guess I didn't realize how the govenor worked and it needs some rpm's to actuate it. Things are comming together now. Thanks
PatRarick Posted October 29, 2003 Posted October 29, 2003 You need to pull the engine and remove the blower housing (front cover of the engine) to replace the coil. Since it has been sitting, that's not a bad idea anyway. Could be mouse nests or other garbage in there which will cause serious problems very soon. I opened one this past summer that had enough cat food to bury the coil. There are other opinions out there, but I would go with keeping the original magneto system. In my opinion, it doesn't seem to be as hard on points as the battery ignition, you don't have to do any additional wiring, and you can run without a battery if you have to. Pat
beuce Posted October 29, 2003 Author Posted October 29, 2003 Thanks for everyones help, I will replace the coil and see if things improve.
beuce Posted November 4, 2003 Author Posted November 4, 2003 I ended up replacing the coil this weekend, but my problem still is there. I have new points, condenser, plug, NGK screw on plug boot, and coil. It looks like I have a good spark, but do not have a inline tester yet. When I start the tractor it idles up but sputters unless I push down the govenor arm or close the butterfly on the carb manualy. When I do that it "seems" to idle fine, but as soon as I let go the rpm's increase slightly but then it sputters, it does keep running though. Now I am thinking that I may need a carb rebuild? What do you all think?
rjgoth Posted November 4, 2003 Posted November 4, 2003 I am taking an educated guess here in stating that it couldnt hurt to go through the carb and make sure everything is up to snuff, that would eliminate another source for the problem at least. When rebuildign the carb, make sure and check the throttle shaft for any sloppyness in its bushing. When you assemble it and bolt it back to the engine use all new gaskets and check the gaskets with a thin .002" feeler guage, this will show you if there are any air leaks in your intatke system as well as the carb. Pay very close attention to the float bowl, high speed and low speed needle valve adjustments. I would double check the points to make sure they are set at .020". Double check the govenor linkage to make sure it is operating freely with no binding. Make sure the springs are the correct ones from briggs and stratton -- not off the shelf hardware store springs. I will go further and say to remove the head and check for any excess carbon buildup on the head, piston, and the valves. Make sure the valves are seating properly and that they are not stuck. Replace the head gasket and re-torque to spec. I know this is alot and probally excessive but by eliminating as many problem variables will help with trouble shooting. I had LOTS of trouble with an engine like this on my previous tractor and I know they can be very very finiky. Best of luck to you. Ryan Let us know how it turns out.
MPH Posted November 5, 2003 Posted November 5, 2003 You say it increases in Rpm slightly when you when you let go of the butterfly, that could just be it coming up to the speed your throttle linkage is set to idle at. Does it run if you open it up more? be careful not to over rev it..MPH
beuce Posted November 5, 2003 Author Posted November 5, 2003 Ryan, I will try what you suggest, I am hopping the carb rebuild will fix my problems. MPH, when I start my engine the throttle is wide open because of the govenor, and will sputter unless I manualy push down the arm or close the throttle at the carb. When I do that it seems to idle smooth. When I release the govenor arm or throttle at the carb the throttle opens up all the way and it increases only slightly in rpms and sputters. I am thinking maybe high speed jet???? Thanks everyone!! brian
MPH Posted November 5, 2003 Posted November 5, 2003 Ok, Does it smoke black as it sputters? if so its flooding, if not it starving. Take carb apart and at least give it a good cleaning to see if it helps. If it does, kit it. Be sure you buy or make a screwdriver to get the high speed jet out WITHOUT scrapping the treads up, the one on the 16hp were almost gone. The 16hp briggs I brought home had a carb so crudy it rotted out the bowl, new parts for me are 205 miles away, so just to see if it run I just cleaned it up, all used parts, and she's pretty smooth. I'll rebuild kit it before I use it. MPH
beuce Posted November 5, 2003 Author Posted November 5, 2003 Black smoke and I can also see gas pooled up on the air cleaner side. I kinda figured it was getting too much gas, but have no idea on how to stop it. I was going to rebuild the carb, but I can't get the high speed jet out because it is already screwed up, so I brought it in to a shop so they can try to work thier magic. Hopefully I will have it back before this weekend.
rjgoth Posted November 5, 2003 Posted November 5, 2003 Like I mentioned in a previous reply to you to make sure the float is set correctly. To do that turn the top half of the carb assembly upside down with the float, needle & seat in place. Holding it upside down will close the float valve. The float should sit absolutly parallel with the carb body. The briggs repair manual explains this also. I am assuming this is why you are seeing gas pooling up inside your carb body is because your float is not closing once the bowl is full of fuel. This in turn is making your engine run rich which is causing the black smoke as MPH stated. Good luck with it. :) Ryan
MPH Posted November 5, 2003 Posted November 5, 2003 Too bad on the screwed up high speed jet. Guess it took me half an hour to get the one out on the 16hp, lots of back and forth turning and PB and Wd inbetween. Its so simple to grind down a 99 cent screwdriver to fit rt it boggles me mind why people me mess those up so commonly..Hope the shop wins out.MPH
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