View Full Version : toro smowthrower reving

12-14-2007, 09:47 PM
Any ideas?

started up my snowthrower today and the engine revs up and down when I open the choke and throtle up the engine.

12-14-2007, 10:09 PM
if it is a 2 cycle then it is possibly the carborator. If a 4 cycle then it might also be a dirty carborator and the mixture screw might be a little off. I dont know what kind of engine it is so its hard to to tell you the problem. Mentioning what kind and brand would help.

12-14-2007, 10:13 PM
Its a Toro Powerthrow 622 4 cycle engine.

12-14-2007, 10:28 PM
Its a Toro Powerthrow 622 4 cycle engine.
do you know the brand and horsepower?

12-14-2007, 10:46 PM
Tecumseh horsepower ?

12-14-2007, 10:47 PM
6 horsepower

12-14-2007, 11:17 PM
It probably sat all summer with gase in it. If this is the case then you might have a dirty carborator, the main jet is probably partially clogged so all you would have to do is unscrew the jet and clear out the tiny hole. before you take the carborator apart you mught want to adjust the carb setting and that would be the screw underneath the bowl on the bottom. Just start the engine and very slightly turn the screw counter clock wise maybe only a quater turn and the engine should smooth out. If it doesnt smooth out then turn it the other way slightly. If nothing changes then you should clean out the carborator, which isnt very difficult. Also make sure the fuel is on first.

12-15-2007, 10:08 AM
Without model and serial number(found on a silver tag someplace on the frame) it's difficult to tell whether you have a fixed or adjustable main jet. A fixed main jet will not protrude more than 1/4" from the bottom of the carb bowl. If a fixed main jet, remove it and clean the three orfices. If it is an adjustable main jet there will be an adjustment screw in the main jet. Remove the bowl nut/main jet assembly and back out the adjustment screw taking care not to lose the washer and sealing o-ring. Near the threaded end of the jet, just as the smooth portion begins there is an small orfice running at an angle into the central part occupied by the adjustment screw. Clean up and replace. Start and check running condition. If not improved you should do a complete carb clean up and rebuild. I have done a rebuild on the carb without removing from the engine but it is a lot more convenient to remove the carb. You will need Tecumseh #631021A rebuild kit. In addition, if the carb has a fixed main jet, you likely find the carb has a blue, green or yellow plastic emulsion tube which is sealed by two o-rings, #632547. The emulsion tube can be partially pushed out by reaching into the throat of the carb with a flat screw driver. With a very small pair of needle nose pliers it can then be pulled out of the bottom. The o-ring that is furthest into the carb will usually remain there so make sure it is removed before replacing the tube with the new o-rings.

If you can find the model and serial number, you can go to www.toro.com then click on homeowner which will allow you to go to a parts lookup where you can get a better idea of what to do.

Don't know if this will help--but good luck.