Chevrolet 12638426 Camshaft Asm

The camshaft bearing caps are numbered consecutively starting with the front of the engine; lettered either 'I' for intake or 'E' for exhaust; and bear an indentation pointing forward. For this procedure, special timing chain holding tools EN 48383-2 and EN 48383-3 are required; otherwise the timing chain cover has to be disconnected to keep the chains on the lower sprockets. First of all, you shall have to remove the negative cable of the battery, the valve cover or covers, the power steering fluid register, the lower intake, the CMP sensor and the camshaft position actuator solenoids. If for some reason it is necessary to remove the left-side camshafts, then it is necessary to pull out the high-pressure fuel pump. Tilt the engine in way that the camshaft flats are on the top, and in line with the plane of the cylinder head, then measure the endplay with the help of the dial gauge. Using an open-end wrench, hold the camshafts and use a socket wrench to remove the camshaft position actuator bolts. In place the special tool that clamps the timing chain and sprockets and mark match points on the actuators and the chain. Take out the bolts for the camshaft actuator and the actuators themselves, and put the bearing caps in a box named for later replacement. Camshaft bearing cap bolts 022 082: slacken and remove in reverse order to the torque sequence 134 Nm, and check the camshafts for wear or damage by measuring the journal diameters and the lobe heights. It is advised to remove the camshaft for cleaning and afterwards check the bearing journals for any sign of wear, pitting or seizure of the camshaft Journal and the bearing while the shaft and bearings are replaceable if damaged. Bearing journals and camshaft lobes; the wear should be gauged with Micrometrical measurements tools and appear as dark and glossy due to heat. The inside diameter of each bearing should be measured in order to check the oil clearance and if found to be very high, new bearings are required. In camshaft bearing replacement, precision and specialty tools coupled with technical know how is needed and hence, the block should be taken to an automotive machine shop. Some of the checks to be made are that sealing rings are fitted, and camshaft bearing journals together with lobes need to be lubricated. Position the camshafts back to the bearing journals low tension area before applying engine oil on the bearing caps before finally reinstalling them back in their respective positions while their arrow face the center of the cylinder head. Torque the bearing cap bolts to 200 lb-in in the sequence mentioned above and do the same thing for the left side cylinder head camshafts. The rest of the procedure is the reverse of the above order and, before engaging the engine, the oil should be changed and a new oil filter fitted.

Before lifter removal, it is important to store them in a clearly labeled box to ensure they are reinstalled in their original locations.