Thank you for your question.
Usually when the tire has leaked, all the air out it is because the bead does not seal very good to the rim. First, I recommend using a bead sealer on the rim and the tire. This will help seal the tire to the rim. To get a tire back on the rim use a ratchet strap wrapped around the tire. When you start to ratchet the strap tighter the bead will start to push outward to the rim. Now put some air in the tire to seal the tire to the bead. Remove the strap and adjust the tire pressure.
You can also just use a piece of rope and a stick; hammer handle, etc. to make a tourniquet. Twist it up until the rim seals and add air. The ratchet tie down, if you have one handy, is a better method, though.
To repair a leak in a tire I have use a tire sealant with the brand name of slime that has worked well. You will have to place a block under the frame of the snow bower to take the weight off the tire. If the weight is on the tire, it is more likely to come off the rim. Now remove the valve core from the valve stem and squirt in the recommended amount. Clean the excess off the stem and reinstall the valve core. Inflate the tire to the recommended pressure. Plugging the tire with a tire plug kit will also work. You can check out this link.
You can have it repaired at your home if you like by a Sears technician. Here is a link for the website:
Sears Home Services
I hope this is helpful.
Please let me know if you have any other questions.
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