Generac QT 3.9L 40kW — Preparation for Start-Up
Installation · Generator set
For the Generac QT 3.9L 40kW, from the Generac owner's manual.
Applies to: Generac QT 3.9L 40kW, Generac QT Series, Generac V-type engine
Before you start
- Ensure AUTO/OFF/MANUAL switch is in OFF position before working on the generator.
Procedure
- Ensure 120VAC circuit breaker to battery charger is open.
- Remove the fuse from the control panel (H-100/R-series: 15 Amp ATO fuse).
- Connect battery cables; attach negative cable last.
- Close 120VAC circuit breaker to the battery charger.
- Insert the fuse into the control panel.
- Move AUTO/OFF/MANUAL switch to MANUAL; engine should crank and start.
- Check voltage at generator terminals and check for leaks.
- Close generator main line circuit breaker; turn generator set off.
Tools required
- Manometer Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Battery charger must be connected to 120 VAC, 15 amp circuit
- Record static gas pressure; must be as listed in Specifications
Full service-parts list: Generac QT 3.9L 40kW →, Generac QT Series →
Source: Generac owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.