Hi-Dump Operation
April 5, 2005
Lift Switch Operation
1. Pump runs.
2. The valve solenoids do not activate. Oil goes thru the valves to the cylinder.
3. The relays are not energized. Current goes thru in their normal position.
Dump Switch Operation
1. Both relays are energized.
2. Both valve solenoids are activated.
3. The pump runs.
If the switches are good suspect one of the relays. Even though we have not seen any of the
relays fail to date we are going to higher rated relays . When you engage the dump switch
you should feel the relays energize.
If the pump does not run most likely the problem is a relay.
If the pump runs but the cylinder won't move the problem could be a stuck valve or one of the
solenoids on the valves not activating.
Another area to look at is the terminals in the relay plugs. They push on very hard and
sometimes a terminal will back out as the plug goes on.
