Diesel fire pump engines with 24-volt starting systems rely on the 1804A-24 engine start solenoid (P/N 535-0098) to engage the starter. Rated for 24 VDC battery banks, it acts as the heavy-duty switch in the cranking circuit, energizing when the fire pump controller initiates a start sequence and dropping out once the engine is running.
Replace the start solenoid if the engine fails to crank during the weekly test, cranks from one battery bank but not the other, or the solenoid chatters audibly instead of pulling in cleanly. Because fire pump engines crank automatically on a regular test schedule, solenoid contacts see frequent duty — many service techs keep a spare on the shelf to avoid a no-start condition.
Fits diesel fire pump engines using 24 VDC starting power; if your system is 12-volt, see our 1804A-12 solenoid instead. Veteran-owned Cybertronic Controls stocks engine parts in Hammond, Louisiana — call 985-351-5681 with your engine model to verify compatibility.