Engine Parts 2.5L 150 cui AMC Jeep CJ7

Why the 2.5 Litre AMC in the Jeep CJ7 Needs a Rebuild After Decades.

With the 1983 model year, the 2.5l  AMC four-cylinder replaced the bought-in GM engine in the CJ7. Its cast-iron block, a timing chain instead of a belt and hydraulic lifters made it a long-distance runner – yet four decades on, its limits are plain to see. The timing chain stretches and slaps against the guide, piston rings lose tension and let oil into the combustion chamber, and bearing shells on crankshaft and connecting rods wear with every cold start. Cork gaskets on oil pan and valve cover harden, valve stem seals turn brittle, and the motor mounts sag under the weight of the block. Rebuilding the four-cylinder rather than merely resealing it restores compression, oil pressure and smooth running – and prevents the consequential damage that a stretched chain or a worn rod bearing causes all too quickly.

• Gaskets and gasket sets: From the cylinder head gasket through valve cover and manifold gaskets to intake and exhaust valve stem seals; the complete upper engine gasket set and the lower set are stocked as well.
• Pistons, rings and bearing shells: Piston sets in standard size and in .030" and .060" oversize, matching piston ring sets, main bearings for the crankshaft plus connecting rod bearings in standard size and oversize – along with rod bolts and nuts.
• Timing and valve train: The three-piece timing set with chain tensioner and guide, the timing cover with gasket, camshaft bearings in standard and oversize, plus hydraulic lifters and rocker arm pivots for the head.
• Oil circuit: Oil pump, oil filter, drain plug with sealing ring, the PCV grommet in the valve cover and the oil pan gasket set in cork or as a one-piece silicone gasket.
• Engine mounting and power transfer: Motor mounts for left and right, transmission mount and insulator for the Dana 300, the crankshaft harmonic balancer, pilot bearing and the flywheel ring gear for vehicles with manual transmission.
• Intake and exhaust side: The exhaust manifold set including gaskets, the pre-heater hose from manifold to air cleaner, the carburettor vacuum switch and expansion plug sets in steel or brass.

American Engine-Building Expertise from Crown to Sealed Power.

Crown Automotive and Enginetech from the USA form the backbone: Crown covers gaskets, covers and bolt-on parts to OEM specification, while Enginetech stands for timing sets, pistons and bearing kits from American engine building. Sealed Power supplies main and rod bearings as well as pistons in standard and oversize, Dorman adds manifold sets and small parts, and Standard Ignition the vacuum switch for the carburettor version.

Your Contact for Oversizes, Torque Figures and Assembly Order​​​​​​​.

Unsure which oversize fits after the crankshaft or cylinder bores have been machined, or in what order timing cover and oil pan should be sealed? Talk to us – we will give you torque figures, the correct assembly sequence and check compatibility with your VIN. Parts ship from stock in Germany, usually within the next business day.