20 Most Recent Husqvarna 26 Hp 54" Deck Zero Turn Riding Mower Questions & Answers

Quick an easiest way to isolate the problem whether fuel or spark/compression is with starter fluid (or carb cleaner or flammable brake clean).

To use starter fluid, remove the air filter and set aside. Set throttle low/choke off. Spray a 1 second burst directly into the intake. Leave air filter off and promptly start.

If it fires and runs a few seconds and dies then likely no fuel delivered from carburetor. Remove spark plug, if dry them no fuel delivered from carburetor. Check operation of anti afterfire solenoid, water in carb fuel bowl, other.

If it does not run then either flooded, no spark, or low compression. Remove spark plug. If plug is wet then either too much fuel, no spark, or no compression.

sounds like a safety switch most likely the one for your brakes

https://www.lawnmowerforum.com/threads/is-there-a-best-tire-pressure.31615/ This forum has good information of the correct/best pressure fot the tires.

Owners Manuals You can download manuals from this site, this may help troubleshoot the problem. Have model number ready.

Wrong belt or not fitted correctly.

Yes. Your mower is running directly off the battery

I'd check the belt tension. Could be the tension idler arm is sticking or the spring needs to be adjusted.

Exmark Premium Hydro Oil. I was not able to find a cross reference.

You didn't give the model number but from the manual I read it is sealed. "the transmission is maintenance free with no need for level checks or oil changes. If a leak occurs, replace the unit or contact your Husqvarna dealer" http://www.husqvarna.com/ddoc/HUSO/HUSO2010_USen/HUSO2010_USen__115384327.pdf

If it's the belt that just runs on the deck and not the one that goes to the engine, it is a 954-0349