Engine Parts 3.8L & 4.2L 6-Cylinder Jeep CJ6
Timing Set, Pistons & Valve Train for the Six-Cylinder (1972–1975).
Why the AMC Six-Cylinder Needs Attention After Decades of Service.
Starting in 1972, AMC replaced the aging 2.2-liter F-Head four-cylinder in the Jeep CJ6 with the significantly more powerful six-cylinder engines displacing 3.8L (232 cui) and, from 1975, also 4.2L (258 cui) – the standard powerplant until CJ6 production ended in 1975. After decades in service, typical wear patterns show up: the timing chain stretches and can jump timing, the timing chain cover and its gaskets start leaking, and valve seats and valve stem seals wear out from heat and carbon buildup. Main and camshaft bearings lose clearance from oil sludge and abrasion, rod bearings and main bearings wear out, and the crankshaft seals along with the oil pan gasket harden and start leaking. Anyone fully overhauling their CJ6's six-cylinder or troubleshooting rough running and oil loss will need to replace these classic wear parts.
- Cylinder Head & Valve Train: The valve seal for intake and exhaust valves and the valve cover gasket for the steel valve cover.
- Timing Chain & Camshaft: The complete timing set and the standard-size camshaft bearing set.
- Crankshaft, Rods & Bearings: The connecting rod bearing complete set and the standard-size main bearing set.
- Pistons & Gaskets: Standard-size piston rings along with the lower engine gasket set for the lower-end overhaul.
- Oil, Cooling & Hardware: The oil pump with inlet tube and the PCV valve for crankcase ventilation.
American Engine Expertise for the Six-Cylinder.
Main, camshaft and rod bearings along with valve seats come from Sealed Power, while the timing set, standard-size camshaft bearings and piston rings are supplied by Enginetech. The timing chain housing, connecting rod bolts, oil pump, gasket set and most remaining parts come from Crown Automotive. Standard Ignition rounds out the range with the PCV valve, and a heater hose is also available from Dorman – five American brands that together stand for proven US engineering in the classic AMC six-cylinder.
Your Partner for the Six-Cylinder Engine Overhaul.
Whether it's a single gasket, a new timing set or a complete bearing overhaul with the right oversizes, we're happy to advise on torque specs, assembly order and compatibility with the CJ5, CJ7, CJ8 and Wagoneer/J-Series models sharing the same engine. Orders ship from stock within the next business day, so your overhaul can keep moving forward.