TAKUMI R5B12-77 Spark Plug BERU Ignition Spark Plug For 18GZ6-77-2 DENSO GI3-1 GI3-3 GI3-5 ALTRONIC L1863IP BG RB777-1
TAKUMI's factory advantage: advanced equipment, experienced engineers and a zero-defect mindset. Every plug is tested before it leaves the workshop.
Product Overview
TAKUMI R5B12-77 spark plug. TAKUMI R5B12-77 iridium industrial spark plug, cross-referenced to Champion RB77WPCC / Denso GI3-1 / Altronic L1863B family.
Every TAKUMI unit is produced in an ISO 9001 and IATF 16949 certified factory, 100% tested before shipment. The plug is engineered for long service life in continuous operation, with a nickel-plated shell, copper-core electrode and high-grade ceramic insulator.
Key Specifications
- TAKUMI TypeR5B12-77
- Thread SizeM18 x 1.5
- Reach20.6 mm (13/16")
- Hex Size22.2 mm (7/8")
- Seat TypeFlat
- Spark Gap0.3 mm
- Heat Range77
- Electrode TypeIridium / Double J
- ResistorYes
Cross Reference
- ChampionRB77WPCC / KB77WPCC / RB77CC / PB78WPC / RB77WPC
- DENSOGI3-1 / GI3-3 / GI3-5
- ALTRONICL1863B / L1863IP / L1863DP
- Federal Mogul / BERU18GZ4-77 / 18GZ6-77-2
- C-A-T243-4291 / 301-6663 / 194-8518
- WAUKESHA60999Z / 69919D / 69919Z
- C-U-M-M-I-N-S4098162
- GUASCOR7664292
Applications
- CAT G3500 series (G3508 / G3512 / G3516 / G3520)
- WAUKESHA gas engines
- C-U-M-M-I-N-S Q19G
- Industrial gas generators
Advantages
- Drop-in replacement - no engine parameter changes required
- Reliable ignition under high pressure and lean combustion
- Anti-corrosion nickel-plated housing
- 95% alumina insulator for heat and shock resistance
- Monolithic resistor for stable conductivity
- Factory direct with competitive pricing and short lead time
OE numbers are for reference only. Final fitment should be confirmed before ordering.
Factory & Quality Control
In our quality laboratory, every production batch is inspected with precision gauges, high-voltage spark testers and sealing equipment before packing.
Production Workshop
TAKUMI runs a fully integrated manufacturing base: CNC machining, automated assembly and 100% functional testing under one roof.



From raw material to finished spark plug, every process is controlled in-house with ISO-certified procedures.
Get in Touch
Have questions about our products or want to discuss a custom order? Our team is ready to help you.

