OEM 2004 Jeep Grand Cherokee Exhaust Valve

2004 Jeep Grand Cherokee Exhaust Valve Parts and Q&A

• Q: How to Service and Repair Exhaust Valve and Intake Valves on 2004 Jeep Grand Cherokee?

  A: To service and repair the valve, start with cleaning of all the carbon deposits on the combustion chambers, valve ports, valve stems, valve stem guides and the head. Reface the intake and the exhaust valves to the prescribed angle using a valve refacing machine but leave a margin of not less than 0.787 mm (0.031 in.). in valve seat refacing fit a valve guide bore pilot, of correct size, into the valve guide bore, and with a good dressing stone, reface the valve seat to required angle and only sufficient to produce a smooth finish, use tapered stones to add/ remove required seat width as required and keep valve seat runout to maximum 0.0635mm (0.0025in.). To measure valve stem to guide clearance, remove the valve head, clean the valve stem guide bore and insert telescoping gauge into the guide bore about 9.525 mm (0.375 in.) away toward the valve spring side of the head, using a micrometer and comparing crosswise crosswise to lengthwise dimensions; should crosswise to lengthwise difference be greater than 0.0635 mm (0.0025 in.), then ream the guide bore to oversize valve stem. Also check the valve guide bore diameter against specifications (7.95 - 7.97mm or 0.313 - 0.314 in.); when it is off more than 0.076mm (0.003 in.) ream the guide bore. Alternatively, with the valve in place measure lateral play of the valve stem by using a dial indicator; correct clearance is 0.025-0.0762 mm (0.001-0.003 in.) but should it be any greater than this, then ream the valve guide. There are a couple of tips to remember: always grind valve seats after reaming to assure concentricity. To remove, having removed the engine cylinder head, compress each valve spring using a Valve Spring Compressor Tool MD-998771A and then remove the valve locks, retainers, springs and valve stem oil seals, discarding the oil seals. Clean the top of the valve stem of any burrs by means of a smooth stone or jeweler file, then drop the valves in rack in the order in which they have been removed. To install, make the valve stems and valve guide bores clean, lubricate a small amount on the stem, and slide the valve into the original valve guide bore. Put replacement valve stem oil seals on the valve stems, substituting oversize oil seals in the event 0.381 mm (0.015 in.) oversize valve stems are fitted. Rest the valve spring and retainer towards the engine cylinder head, use Valve Spring Compressor Tool MD-998772A to press the valve spring, put on the valve locks and then take off the tool. BANG the valve spring to and fro on the side, with the hammer, making it seat on the engine cylinder head, and also tap the top of the retainer and seat the valve locks, and put on the engine cylinder head.