On Fri, 25 Feb 2005, Lawrence M. Seldin, CMC, CPC
wrote:
I have a Toro 521 Snow thrower model 38052. My problem is that my machine, needs to have me press
the Primer button every 2 seconds for over 5 minutes to let the machine start up. I know to have the
machine start with full choke and the machine on fast.

Is there something I can adjust so I don't have to do this. What happens is, if I don't do this, the
machine dies. However, it is easy to start and will continue to run, as long as I keep pressing the
Primer button.

Sounds like it is too lean and you need to learn how to adjust the carb.
If you do not have the manual, download any manuals you can find from
Toro. They have a manual for mine from 1979, so they should have one for
yours.

You want to open the needle valve enough that it keeps running more
quickly after it starts, and just enough to not bog down to much when
pushed into the snow. If it is a 2-cycle engine and set too rich
(blubbers when warmed up instead of running smoothly), it may foul the
spark plug with oil.