High Idle circuit PT's/FC's

[Ralph L. Fullenwider]

Good morning everyone:

High idle circuit on the PT's;

Power comes from the ignition on cb to the high idle switch on the dash
(some PT's have a manual valve rather than an Allen Air electric valve)
from the switch on the dash to the low pressure (60 psi) switch to the
neutral safety switch. From the neutral safety switch to the Allen Air
valve (high idle which is normally closed)

When the Allen Air valve opens, it sends air to the transducer located on
the left side of the of the engine on the throttle control unit. The high
idle circuit interacts with the throttle control valve, making it more or
less inactive because of the amount of air being supplied to the throttle
transducer. How that works will be explained when I get the write up done
on the throttle control circuit. And I find that system interesting.

High idle on the FC's;

High idle on the FC's is controlled by using the cruise control in neutral.
Turn the power to the on position. then hit the set switch and each time
you do that, the RPM's raise a calculated amount. To lower the amount of
RPM's you hit the decel side of the set switch and the RPM's will drop the
same calculated amount. To cancel the high idle turn off the cruise control
power.

Safe travels,

Ralph and Charolette Fullenwider
Ralph's RV Solutions, Duncan, Oklahoma
http://home.swbell.net/rlf47/index.htm