REMOVAL & INSTALLATION
- Perform the Cylinder Head Removal procedure (for your engine) far enough to gain access to the camshaft bearing cap bolts. If you are going to remove the head anyway, remove the cam after removing the cylinder head.
- Prior to removing the camshaft, measure its end-play with a feeler gauge. The end-play limit is 0.0098 inch (0.248mm) for the 8R-C, 18R-C, 20R and 22R engines; 0.01 inch (0.254mm) for the 4M-E and 5M-E engines. If the end-play is beyond this, replace the head.
- Use a 12mm wrench to remove the bearing cap bolts. Remove the caps. Keep them in order, or mark them.
- Measure the bearing oil clearance by placing a piece of Plastigage® on each journal. Replace the caps and tighten their bolts to 13-16 ft. lbs. (17-22 Nm).
- Remove the caps and measure each piece of Plastigage®. If the clearance is greater than 0.004 inch (0.101mm), replace the head and cam.
- Lift the camshaft out of the head.
- Coat all of the camshaft bearing journals with engine oil.
- Lay the camshaft in the head.
- Install the bearing caps in numerical order with their arrows pointing forward (toward the front of the engine).
- Install the cap bolts and tighten them to 13-16 ft. lbs. (17-21 Nm).
- Complete the cylinder head installation procedure as previously outlined.
A dial indicator, micrometer and inside micrometer are all needed to properly measure the camshaft and camshaft housing. If these instruments are available to you, proceed; if they are not available, have the parts checked at a reputable machine shop. Camshaft specifications are included in a chart in this section.
- Using the micrometer, measure the height of each cam lobe. If a lobe height is less than the minimum specified, the lobe is worn and the camshaft must be replaced. Minimum intake and exhaust lobe heights are as follows:
- Place the camshaft in V-blocks and measure its run-out at the center journal with a dial indicator. On all but the 4M, 4M-E and 5M-E engines, replace the camshaft if run-out exceeds 0.008 inch (0.203mm). On the 4M engine, replace the camshaft if run-out exceeds 0.0012 inch (0.03mm). On the 4M-E and 5M-E engines, replace the camshaft if run-out exceeds 0.002 inch (0.05mm).
- Using the micrometer, measure journal diameter, jot down the readings and compare the readings with those listed in the Camshaft Specifications chart. Measure the housing bore inside diameter with the inside micrometer, and jot down the measurements. Subtract the journal diameter measurement from the housing bore measurement. If the clearance is greater than the maximum listed under Bearing Clearance in the chart, replace the camshaft and/or the housing.