FOR ONAN QG GENERATORS 5500 7000 HGJAA HGJAB HGJAC 167-1638 SPARK PLUG PACK OF 2 RV TRAILER CAMPER

iFJF part No.: FJ-1638. Product Overview Keep your Onan QG generator starting on the first crank with these premium replacement spark plugs. Direct replacement for Onan part number 167-1638 , these plugs are engineered for the high-hour duty cycles of RV generators. Compatible with Onan QG 5500 and 7000 models (HGJAA, HGJAB, HGJAC). Worn spark plugs are the #1 cause of hard starting and rough running in RV generators replace annually or every 150 hours for reliable performance. Key Features Direct OEM Replacement Replaces Onan 167-1638 Nickel-Plated Shell Anti-seize and corrosion-resistant Copper-Core Electrode Superior heat dissipation and conductivity Pre-Gapped Factory-set to OEM specification; ready to install Pack of 2 Both plugs for twin-cylinder QG generators Compatibility Generator Model Spec Codes Power Onan QG 5500 HGJAA, HGJAB, HGJAC 5,500W Onan QG 7000 HGJAA, HGJAB, HGJAC 7,000W Specifications Specification Value Part Number 167-1638 Thread Size 14mm x 1.25 Reach 19mm (3/4") Hex Size 5/8" (16mm) Gap Pre-gapped to OEM spec Quantity 2 Pack Frequently Asked Questions Q: How often should I change generator spark plugs? A: Onan recommends spark plug replacement every 150 hours or annually, whichever comes first. If your generator sees heavy use or runs in dusty conditions, consider more frequent replacement. Q: What are signs my spark plugs need replacing? A: Hard starting, rough idle, surging under load, increased fuel consumption, or visible electrode wear/carbon fouling on inspection. Q: Does this pack include 2 plugs? A: Yes, this is a 2-pack enough for both cylinders on the QG 5500 and 7000 twin-cylinder generators. Q: Are these pre-gapped? A: Yes, factory pre-gapped to OEM specification. Always verify gap before installation as a best practice, but they should be ready to install out of the box. Related Products Onan Generator Air Filter 140-3116 Complete tune-up Browse All RV Generator Parts Related Blog Posts RV Generator Maintenance Schedule & Tips