Small Engines (Lawn Mowers, etc.): Tecumseh 3.8hp engine-carb question, steel balls, replaceable unit

Question
Hello,
Please bear with me while I speculate on what i think is the problem with my carb.
The primer on this carb isn't working correctly.  I think there may be a check valve (possibly a small ball bearing) missing from the drilled passage on the intake side of the primer bulb.  When the bulb is operated I can hear air moving but no fuel is forced into the carb throat. If there is supposed to be a check valve there and if it were missing, then it would cause the air in the bulb to move in the wrong direction out of the bulb, thereby failing to force air into the fuel bowl and fuel from the fuel bowl into the carb throat.

Answer
Hi David
Yep- there should be two check valves, one on inlet and one on outlet.  Either one failing will prevent proper operation.  They are usually small steel balls OR little rubber flaps.  Depending on the model, you may have to look hard to find them.  Genrally they are not replaceable.  If you can get a parts list for your model, the primer housing is a replaceable  unit by itself.

Good luck with this (hey- check ebay for a used carb)