VanDervort Repair & Rebuild

185 Shady Hill Road

Apalachin, NY 13732

(607) 625-4658

Tecumseh Primer Cold Start / Hard to Start Problem

To our valued Tecumseh Owners with the Primer carburetors, we offer the following solution to hard starting. The primer works best only when following this procedure.

1) After pulling the start cord, cranking to start, or being run briefly, WAIT 5 SECONDS for the primer well to fill by gravity through a small orifice.

2) After the 5 second wait, depress the primer bulb 2 - 5 times to provide the fuel priming operation. Go to step 3 unless you have completed all steps without success, in which case wait an additional 5 seconds and then depress the primer 2-5 times again (double primed).

3) Wait 5 seconds again then One brisk pull should start the motor. If it does not, go to step one. You may have to repeat this entire procedure three times to start these units cold, once when warm.

If this procedure does not work for you, service may be required.

Let me explain what is happening. Once there is a little age and use, these units become hard to start, yet otherwise are very reliable. Several factors are involved, some require service and others would benefit from service but only extensive service will bring it to like new starting operation. Assuming clean fuel in the carburetor bowl by normal gravity feed, then the primer well will fill through a small hole. As the primer is depressed, gas gets injected into the carburetor throat. On many of the units you can hear this injection, depending on the air cleaner design. If a unit has a lot of carbon and deposit built up, or other conditions, which require even a richer mixture to start, a double or quadruple prime is required. Once the motor is cranked to start, the venturi effect evacuates the well and the injected primer shot(s). The motor either starves out of fuel or establishes normal operation. In any event, it takes a clean carburetor another 5 seconds from this point to fill the well to allow priming to function.