I have a Bolens by MTD 15.5-HP Manual 38" Cut Lawn Tractor
and it ran well earlier today but now cannot get it to start. I have tried new battery, checked fuse its fine, cleaned the filter but nothing seems to get it to run but turns over crank fine..

Reason my ride on mower died to begin with is the following: I hit the reverse button with break/clutch in but forgot to switch the gear to reverse from forward.. Once I started releasing break/clutch i heard a loud popping sound like a shotgun a few times and then the mower died (has not started since)

After pulling hood and watching it spin and visualizing the motor area when I'm attempting to start right after it pops I see a micro spark of electricity near a pipe up front. Down on my luck can't afford to buy a push lawnmower yet this one.. Any ideas?

 

Clean the carb real good Maybe a kit also.

Before you spend any money check your flywheel Key. You will have to take the nut off to check it properly. A backfire will shear a key. It's not common for a key to shear, but it does happen.

When the nut is off take a pic and post it ~~

 

I agree with the flywheel key suggestion. It doesn't happen often on riding mowers but it does happen and what you describe is the classic symptom. I had one today with that problem in fact (odd because I only see it once or twice a year maybe, out of who knows how many riding mower engines I work on).