The owner of this 1974 Mercedes-Benz 280 had only recently got the car and had noticed a little smoke. They asked us to investigate and give it a service.
By the time it arrived at our workshop, it was extremely hard to start. Once running, it produced heavy clouds of smoke and behaved as though it was flooding.
Too much fuel from a small component
We traced the problem to the cold-start injector, which had failed in the open position. It was letting excess fuel into the engine.
A cold-start injector normally provides extra fuel to help a cold engine start. On this car, the failed injector was supplying fuel when it should not have been.
The work carried out
We bypassed the failed cold-start injector on this car, completed the service and repaired a split hose. The Mercedes was then returned to its owner.
That was the approach taken for this particular vehicle and fault. The right repair for another car depends on its fuel system and what the diagnosis shows.
Changes are worth checking
On an older car, a new starting problem or smoke is worth investigating rather than putting it down to age. In this case, finding the source of the excess fuel explained the symptoms.
If your classic is becoming hard to start or has a running problem, talk to Speedwell in Frankton, Hamilton. Call 07 846 2137 or request a booking online.
