Nissan 13202-1KC0A Exhaust Valve

This operation is not a regular service and is only done when the car has high mileage, after having it overhauled or when trying to diagnose a noise or power decrease originating from the valve gear. Things are adjusted by taking out the camshaft and replacing the cam followers which can be in 26 different thicknesses of the scale ranging from 3.00mm to 3.50mm in steps of 0.02mm. Valve clearance is among the critical aspects of an engine and thus requires proper adjustment for efficient engine operation. To check the clearly, draw the outline of the engine on paper and number cylinders in such a way that number 1 must be at the timing chain end of the engine and mark the position of all the valves accompanied by the clearance permitted for it. Shake off the cylinder head cover, set No 1 cylinder at the top centre of its compression stroke. For the given set of valves, take distance between the cam base and the follower, and then note it down. Twist the crankshaft again to get back to No 4 cylinder and check the number of correct clearances for the rest of the valves, and the disparity of the real and required ones. For the adjustments, the followings are required: Micrometer or Dial gauge. If the valve clearance is out though, replace the cam follower with one of the correct thickness, which are listed on the follower. For any removed follower, take the measurement of the thickness to note the level of wear. For the purpose of ascertaining the follower thickness necessary, the calculations should be made on the basis of the value obtained in the clearance measurement whether it is lesser or greater. Remove the follower, fit a new oil to the new one and gently place the new one to the cylinder head. Resurface the camshafts then make sure of the thicknesses of the fitted followers for future use. With all the clearances adjusted, turn the crankshaft several times in order to put down the followers and once again, measure the clearances. Last of all, tighten all the components that were altered for the access of the cylinder head cover.

This operation is not frequent and usually required when there is high mileage, after overhauling the bike, or searching for the noise or power loss that may be coming from the valve gear. To adjust the engine one has to take out the camshaft and change the cam followers which are available in 31 thicknesses varying between 2.96 mm and 3.56 mm every 0.02 mm The valve clearance can be checked with the car still on but if the adjustment is required the car's engine will have to be pulled out. The procedure starts with sketching out the engine and labeling the cylinders and then, undoing the cylinder head cover and stabilizing the automobile properly. The above procedure is done while turning the crankshaft to the next position whereby the camshaft lobes for No. 1 cylinder will be upwards and using feeler gauges, the amount of clearance for each of the valves will be recorded. Whenever any clearance deviates from the maintained value, the cam follower has to be replaced with one of the appropriate thickness. It is to mention here that with the help of the above discussion, the required thickness is determined considering the gap between the optimum clearance values and the measured one. The camshafts are refitted to the followers and, again, it is beneficial to retain records of the thicknesses for future settings. Last, the crankshaft is turned several times to allow the followers to set and the clearances are Checked again before BOLTING on the cylinder head cover and the engine.