Cub cadet LT1018 won't start or crank

Likely the steering gear and pinion and/or bushings have worn down so far at a point that when you steer left to a point, it simply spins the pinion.

The mechanism is easy to see from underneath. Remove mower deck for easier access. Observe the movement of the pinion and gear as you turn the steering wheel. You likely find the teeth are all but gone.

You will likely need other steering related components, especially the two front steering ball joints and possibly shims for the pinion.

Go to cubcadet.com where you'll find diagrams for your specific model.

Since have had to replace the hex bushing at bottom the shaft on an MTD. Recommend you putting back a bronze version instead the plastic version they have.

You should able to access the steering shaft lower though the underside of frame; easier if you remove the deck to give you space to work.You will need to remove the nut and gear. Then you should be pull the shaft out. If replacing the bushing pull just enough so you replace; no need to completely remove it from the mower.

probably need a new steering shaft and gear.

You didn't give the model number of your tractor - but it's likely that it's not the pinion gear, but rather the brass bushing that's just above the gear. The busing keeps the pinion gear meshed with the steering rack gear. Replacing it is a bit of a PITA - but the following link will take you to a YouTube video that shows how to "giterdone".
https://www.youtube.com/watch?v=VSAyPDRSD3w
:)

Had the same problem with my GT1554. There's a hex shaped bushing with a round center that the steering column passes through, found immediately above the gear on the steering shaft, on the top side of the sheet metal. It had worn to an oblong opening and allowed the gear teeth to slip past each other. Replace that bushing. Even if there's a little wear on the teeth, they'll mesh OK after the bushing is replaced.

Even though the teeth on the fan gear are ok, they may have skipped past each other a few teeth. My tractor has a bushing that the end of the steering rod passed through before attaching to the fan gear. The bearing was worn, allowing the steering rod to move, and the fan gear would then to lose it's grip from time to time, eventually making my tractor perform much like yours. See if you can replace that bushing, your issue should be solved.

sounds like teeth on fan gear are worn or steering shaft and gear came away from fan gear. if fan gear worn replace if ok loosen lower steering shaft mount push tward fan gear and tighten, grease front steering spindles. or may need to replace spindle bushings.spindles too tight causing fan gear priblem

Sorry I don't have a solution but have a similar problem. I replaced the steering pinion gear in hopes that would resolve the problem, but it didn't. The steering pinion gear is located at the bottom of the steering shaft and turns the steering gear. Looks like the steering gear needs to be replaced as well. The nuts securing the steering gear are accessible in the same area as the pinion steering gear. I am going to order a replacement steering gear and attempt to replace it.

-same problem, relatively easy fix. As you look at the 2 meshing gears, you will see the center gear (at the end of the steering shaft) has a nut on it. Remove that nut using an 11/16" socket wrench and pull the gear straight down (don't loose the washer). Now raise the steering column straight up from the top. From underneath, use your finger to pop the worn "bearing" (it's really a bushing) up from it's holder. You will need to fish it out from the upper side. Replace this "bearing"--Cub Cadet # 941-0656A [replaces 741-0656A]
Bearing, Hex Flange, 5/8. Reassemble in reverse order. Hope this helps.