won't start

I’ve been working on getting a Z225 back up and running. It’s had 2 engine replacements (it’s about 20 years old), the last one being 8 or 9 years ago. It’s currently cranking, but won’t catch. If I spray some starter fluid in the air intake, it’ll ignite a few times, but then continues to just...

I have a Troy Bilt TB430 my neighbor asked me to look at It won't start. First thing I noticed is he was not using the correct fuel mix. He has some of the canned premixed fuel 50:1....uggg and he left the fuel in it for months (grrrrr) I have spark, and compression (95 psi, don't know what...