Many small engines have replaced the choke with a primer - a rubber bulb or
button that is supposed to be pushed several times before attempting to start
the engine. Under the right conditions, this is a very effective approach.
However, here are a couple of things to keep in mind:
|NotTaR of small Gasoline Engines and Rotary Lawn Mowers : A primer on priming
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- The number of times the manufacturer recommends for pressing the primer
is just an average - in many cases, more is better and won't hurt. (The
instruction manual probably even says something like: "If the engine doesn't
start and run after N pushes of the primer, do it N more times and try
again"). While it is possible to flood the engine with too much priming,
it would probably take more than just 2 or 3 times the recommended number
- If the ambient temperature is low, priming will be less effective.
The engine may run for a few seconds and then die since its interior parts
having heated up enough, requiring repeated priming and starting. If the
engine then runs fine, there is probably nothing actually wrong. If you work
at it, this might be a good excuse to put off the first mowing of the
Where behavior seems to have changed, first confirm that environmental
conditions are the same and the gasoline is fresh before blaming the engine
on starting problems.
If the engine operates normally once started (assuming you can get it started
by some other means like squirting some starting fluid into the cylinder),
then dirt may have made its way into the priming mechanism. Disassembly and
cleaning may be all that is needed. However, there really isn't much to it:
Pressing the primer just pushes some air into the carburetor, which squirts
some gas via the main carburetor jet to the intake pipe. There really isn't
much that can wrong as long as the rubber primer bulb and connecting tubing
(if the primer isn't on the carburetor itself) is in good condition.
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