Ultrasonic cleaning vs carb cleaner spray: what actually works
Why aerosol carb cleaner can't fix a blocked carburettor — and how ultrasonic cleaning clears the tiny jets and passages that sprays and wires never reach.
Every classic and small-engine owner has a can of aerosol carb cleaner on the shelf. It has its uses — but when a carburettor is genuinely blocked after standing, spray alone almost never fixes it. Here’s why, and what does.
The problem: microscopic passages
A carburettor meters fuel through jets and drillings that can be smaller than a human hair. When old fuel dries, it leaves varnish and gum that plug these passages completely. Aerosol cleaner sprays down the obvious openings but can’t force its way through a fully blocked pilot circuit or emulsion tube — and poking wire through jets ruins their calibrated size.
Why ultrasonic cleaning works
Ultrasonic cleaning submerges the stripped carburettor in a heated solution and drives high-frequency cavitation through every internal passage at once. Those imploding micro-bubbles reach places no spray or brush can, dissolving varnish without abrasion and without changing the size of a single jet.
What a proper carb service includes
- Full strip-down and documentation
- Ultrasonic cleaning of the body, float bowl, jets and needles
- Every passage verified clear
- Reassembly with your rebuild kit
- Bench-set float height and mixture
The difference on a bike that wouldn’t idle, or a mower that wouldn’t start, is night and day.
Got a stubborn carb? Send it in or drop it off and we’ll get it running right.