got a b1p serial number moxy water truck problem is engine over heats engine the followed by trans check thermostat and water pump all good drive around temperatures all good as soon as u activate the water pump engine starts to over heat any suggestions
Use tempature gun to check Tempature differential across radiator.
Checking the temp drop across the rad (top hose to bottom hose should be about 12 to 15 degree drop) is the best place to start as mentioned above. The hydraulic drive fan has a speed control solenoid mounted on the shroud near the bottom right rear of rad package. Unplug the solenoid which will make the fan go full speed and see if that helps. You can also check fan speed if you have a tach. Give the rad a good blowing out with high pressure air too. Check the hydraulic oil temp too , there will be a cooler for hydraulic oil by the rad. It may be due to a hydraulic problem if its only when you run the water pump .
You say the problem occurs after the water pump is engaged, so it makes me wonder if the hydraulic oil is not being cooled. The high continuous flow required for water pump use will overheat the relatively small volume of oil in the system quickly if the piping is not routed through the water tank for additional hydraulic cooling. The heat from the hydraulic cooler could be causing the rest of the systems to overheat.