I recently acquired my first forklift, a 2008 Toyota 8fgcu25 with 7,100 hours on it.

It starts up cold fine. After warming up even somewhat, it's hard to restart. I have to give it a small amount of throttle while turning the key to restart when it's warm or hot.

The idle quality is decent until it warms up completely then it runs a little rough, especially coming off high throttle back to idle.

I changed the engine oil and filter, as well as the spark plugs, wires, distributor cap and rotor button.

I have not yet checked the ignition timing, I need to see if I still have a timing light around. I haven't checked the idle speed either.

One of the previous owners removed the tamper cap on the idle mixture screw on the regulator. Would it be wise for me to mess with that and adjust it until it runs better? I don't have a CO analyzer, so I definitely don't want to lean it out and burn up the engine.

Is there anything else I should check?