Rexco 81 Carburettor Cleaner: What It Fixes, and What It Can't
A generator that will not start. A brush cutter that idles then dies. A water pump that sat through a wet season unused. A bike that has been parked for two months.
In Singapore these are usually the same fault: stale fuel. Heat accelerates the breakdown of petrol, and what it leaves behind is gum and varnish — a sticky amber residue that coats the inside of a carburettor, blocks small passages and glues linkages in place.
Rexco 81 Carburettor & Injector Cleaner is a high-energy solvent built to dissolve exactly that.
What it actually does
It dissolves carbon, varnish and gum deposits, penetrates quickly into small passages, frees a jammed automatic choke, and cleans the linkage mechanism so the throttle moves smoothly instead of hanging. It leaves no residue, and it includes anti-corrosion additives so you are not trading a deposit problem for a rust one.
It is acetone free and chlorine free, which is relevant for the plastics and rubber components that modern fuel systems are full of.
Where it works best: small engines
This is where the result is most dramatic, because small engines have small passages and tiny amounts of deposit cause large symptoms.
Generators, brush cutters, hedge trimmers, water pumps, pressure washers, outboards, and older carburetted motorcycles. If a machine ran fine, sat unused for weeks or months, and now will not run properly, deposits are the first thing to suspect and this is the right can.
The symptoms that point here: hard starting, running only on choke, dying at idle, surging, a throttle that hangs open, or an auto choke stuck closed.
Be honest about fuel injection
Most modern bikes and every modern car are fuel injected, and this is where expectations need managing.
On an injected engine, Rexco 81 is genuinely useful for cleaning the throttle body, the throttle plate and linkage, the idle air passages and external components. Carbon on a throttle plate causes rough idle and poor throttle response, and cleaning it is a real job with a real result.
What an aerosol cannot do is clean the injectors themselves. They sit downstream, sealed in the fuel rail, and nothing you spray into the intake reaches their spray tips meaningfully. Injector cleaning is an in-tank treatment that passes through the fuel system, or a workshop job on a bench rig.
Anybody who tells you a spray can cleans injectors through the intake is selling you something. We would rather you heard it from us first.
How to use it
Engine off and cold. Not warm, not just switched off. You are spraying a flammable solvent near a fuel system.
Work outdoors or somewhere genuinely ventilated. No smoking, no sparks, no grinder running in the same bay, no hot exhaust nearby.
For a carburettor: remove the air filter so you are not soaking it. Use the straw to direct short bursts into the throat, the idle passages and onto the linkage. Work the throttle and choke by hand while wet so the solvent gets into the pivots. For heavy deposits, repeat rather than drowning it in one go.
For a throttle body: with the intake ducting off, spray onto the plate and bore and wipe with a clean lint-free cloth. Open the plate by hand to reach the back of it.
Let everything dry before starting. Expect some smoke on the first run as residue burns off — that is normal and clears in a minute.
Reinstall a clean, dry air filter. Putting a solvent-soaked filter back is a fire risk and a running problem.
What it will not fix
Deposits are one cause of poor running, not the only one.
It will not fix a worn or out-of-adjustment jet, a perished diaphragm or float needle, a blocked fuel tank vent, a failing fuel pump, worn rings or valves, a weak spark, or a carburettor so far gone that it needs stripping and an ultrasonic clean.
The honest test: if a clean improves things and then the fault returns within days, the deposits were a symptom and something else is causing them — usually fuel that is sitting too long, or water in the tank.
Which points at the real fix for seasonal equipment: run the carburettor dry before storing it, or use fresh fuel. Prevention is cheaper than any can.
Sizes and safety
300ml and 500ml.
This is the most flammable product in the Rexco range in use, because of where you use it. Ventilation, no ignition sources, eye protection, and keep it off your skin. Store it out of direct sun and out of a parked vehicle — a pressurised can in a hot car boot in Singapore is a genuine hazard rather than a theoretical one.
The rest of the range
See our guide to what each Rexco number does, or the motorbike maintenance guide if the machine in question has two wheels.
Come and ask
Describe the symptom and we will tell you whether a can is the answer — including when it is not.
645 Geylang Road, Singapore 389575 — +65 6546 7446
2 Gambas Crescent #03-19, Nordcom Two, Singapore 757044 — +65 6255 3446
WhatsApp +65 8978 9808, or browse the full Rexco range.