Engines

                                                      

First day of taking apart an engine was really exciting stuff I had to remove the casing of the engine which was pretty straight forward. First task after removing the casing was to check the timing of the camgears. The way to check if the timing was right is there are alphabets on the camgear and the camshaft, these alphabets must be alined. We now have to remove the cylinder from the block, my task was to work on cylinders and my partner had to work on the blocks. First thing we had to do was see if there was any warping on the surface. I used a long straight ruler and run through the top of the cylinder and see if there was any uneven spots. Warping can be cause by excessive heating and makes it uneven, a solution to fix this is to mill it down. Next was to inspect the inlet and exhaust valve guides, all of mine passed, in this inspection I will be looking for any damage like excessive heat, denting and scratches, if there are they will be replaced.

First task i have to do was checking valve guide clearance, we used a ball gauge to measure the valve guide. I had to measure the top, middle and bottom, also spin it 90 degree angle as well. The results I have did not change fluctuate, valve guides can be damaged if there is excessive heat expanding the guide, the way of fixing it is replacing the guide. Next was to measure the valve stem with a micrometer, the reason for this is because during inside guide there is a lot of heat and force which can bend the stem, stretch it and also compress it, but modern cars now have valve caps which prevents this from happening. The only solution is to replace the valve stem. Now we have to calculate the valve stem to guide clearance, the way is the valve guide minus the valve stem. 2 out of 4 failed, the reason for failing is it could of expanded by the heat, changing the range, this is dangerous because the valve would not fully close. Now i have to inspect the valve springs to see if the spring would of bent, 1 out of 4 was over the recommended specification. The angle was caused by excessive compression combining excessive heating and so it bent the spring and as cooled it stays at a bent form. Other spring inspection is to check the length, the reason for this is friction with the valve stem cap can make the spring shorter and also the excessive compression will decrease the tension on the spring which shorten the spring.