Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I have a fairly new (5 hours) Honda HS928TA with a GX270 engine. I'm curious as to when and what are the signs that the valves require adjustment.

Thanks in advance for your answers.

I wouldn't be messing with the valve lash until the engine has at least 50 hours on it.  Particularly on a Honda engine.  Factory settings are usually adjusted to allow for the engine to break in without adjusting the valve lash.  It doesn't hurt to take a reading to see what they're at, but if the engine is running well I wouldn't be sweating it anytime soon.  

A mechanically noisy engine is sometimes an indication of sloppy valve lash.  However, as the old saying goes:  "Tappy valve are happy valves."   Valves that are a bit loose is not a problem.  Tight valves are.  The reason being that a valve with loose lash setting will always seat properly.  A tight valve may not completely close thus causing hot gasses to bypass the valve and possibly burn it over time.

If your engine begins to lose performance and it has good fuel flow/spark, clear air intake/exhaust, and sufficient lubrication, that's when I'd look at the valve lash.