Generac QT 3.9L 40kW — Changing Engine Oil
Maintenance · Engine crankcase
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
- Never operate engine with oil below the dipstick ADD mark.
- Do not overtighten the oil filter.
Parts for this job
- 0E7415 Oil filter — Generac QT 3.9L 40kW Amazon eBay $81.99 NAPA $3.59
- 0E7415 Oil filter — Generac QT Series Amazon eBay $81.99 NAPA $3.59
Part numbers from the service-parts lists for Generac QT 3.9L 40kW, Generac QT Series. Verify against your serial number before ordering; some links are affiliate links.
Procedure
- Remove OIL DRAIN HOSE from its retaining clip.
- Loosen and remove OIL DRAIN HOSE CAP; drain oil completely into suitable container.
- Install and tighten OIL DRAIN HOSE CAP; re-install into retaining clip.
- Turn OIL FILTER counterclockwise and remove; dispose of old filter.
- Apply light coating of new engine oil to seal of new filter; install and tighten by hand only.
- Remove OIL FILL CAP; add recommended oil. Do not fill above dipstick FULL mark.
- Start engine and check for oil leaks.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Crankcase oil capacity 4.0 U.S. quarts (3.8 liters)
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.