Toro Blowers Rake and Vac - Electric Blower/Vac - 51573 - Page 8 - Answered Questions & Fixed issues

Let warm up if still does need new spark plug

Try a short burst of starter fluid into the carburetor and promptly pull starter. If it runs for a couple seconds and quits then the carburetor is not delivering fuel.

If it doesnt run on starter fluid then either flooded, insufficient spark, or poor compression / crankcase leak.

replace the ignition coil

I have had the same issue with Toro. Finally took it to a local wizard. AFter about 5 minutes if him trying he suggested it would make a great boat anchor. Once Toro goes out of factory specs, that's just about it. A few lucky folks I know with Toro products either accidentally stumble on the just-right combinations or off to the lake they go.

Check and see if there is a shear or safety pin in one of the drive pulleys that has broken.See if there is a pulley that turns by hand when this happens. Could be one has broken but grabs for a little bit. Also check the drive belt and see if it is slipping Check all the drive areas . BE SAFE BY TAKING THE KEY OUT AND TRYING BY HAND>

Ditto... flywheel key has sheared.

what belt did you change? i assume the drive belt. if it is not exactly the right size it wont work. if it is not routed correctly it wont work. it may have slipped off of a pulley.

The deck belt is not adjustable, it is tightened by the number 26 spring. Spring can loose tension or the belt could be stretched.

incorrectly adjusted

spark plug gap or wrong spark plug. or you tipped it the wrong way and filled the carb bowl with oil

that would be a lawsuit to give out that repair.

belt, cable, trans, engine pulley. pick one

Back firing could be an ignition, or valve timing issue, also check the function of the anti fire solenoid on the bottom of the carb float bowl ( you should hear this click as the ignition is switched on) you can also remove it and watch the centre pin retract when the ignition unit is switched on, next thing to check is that the flywheel key has not sheared, this will involve removing the flywheel, failing this remove the rocker box cover and make sure both valves are moving freely as the engine cranks, it could be a stuck valve.

Sounds like you may have stripped the thread in the head when retightening the new plug :( Can be repaired by using a helicoil, however, quite likely, the head will need to be removed to do so to ensure no junk falls into the cylinder.

The model number you listed comes up as a Murray riding mower. Enter you model number at the Toro web site. I believe the manual will have the wiring diagram. https://www.toro.com/en/customer-support https://www.partstree.com/parts/ also will like have same. Just need the right model number.

it says in your owners manual. or go to toro.com

Operators manual. https://www.toro.com/en/parts/partdetails/?id=17944 Try holding the bypass lever to the right and rocking machine back and forth.