06/19/2026
Before you load your machine on a trailer and drive it to us — check these two things first.
In Part 3 of our engine diagnostic series, we cover two of the most common and most easily fixed causes of exhaust flames, a red hot muffler and high CO readings on propane floor scrapers.
A customer drove 3.5 hours from Fort Worth because their newer machine had flames coming out the exhaust and a glowing red muffler. We changed the air filter and they drove home the same day. The filter was so clogged it was packed half an inch thick with debris — the engine could not get any air and was running like the choke was permanently on.
Check these two things first:
Air filter — a clogged filter starves the engine of air and floods it with more fuel than it can burn. That unburned fuel goes straight to the exhaust where the catalytic converter ignites it — producing flames, extreme heat and dangerous CO levels.
Choke cable on Kohler engines — a bent or melted choke cable can slip into the closed position and choke the engine without the operator knowing. Same result — too much fuel, not enough air, flames out the back.
Both are quick, inexpensive fixes. Check them before anything else.
