In this article we will learn how to check the operation of the crankshaft , and will not affect the main bearings .
Start at the top of the connecting rod . For this purpose , benzene, or flushing fluid to clean the carburettor head from possible particles of oil or varnish . Then set the needle bearing into place and insert the piston pin , so how would you set it in the piston . Finger distribute the center and proceed to checkout.
We need to determine the vertical and horizontal clearance . The presence of horizontal play is determined by sliding your finger diagonally in opposite directions , with a small gap must be present. The most common failure is in the presence of vertical play . To determine this , we try to move a finger inside the bearing up - down .
Clearance between the needle bearing and the connecting rod upper head speaks about deterioration of the latter. In order to see this (if used B / U needle bearing and finger) , replace the separator and the piston pin on obviously new and perform operation again. If the play was gone, the final details are subject to change . If the gap is present , replace the full crankshaft, connecting rod sometimes only if the rest of the shaft are in good condition.
If the above check does not give cause for concern , it is necessary to check connecting rod . However, often the mutual wear takes place . Wash likewise lower rod head from possible particles of dirt , oil and petrol coke with or washing for the carburetor. Next, take out the piston pin and the separator .
Free rod head , hold both sides of the fingers , trying to determine the horizontal backlash . To do this, gently wiggle the connecting rod to the left - right. A small gap must be present and this is part of the norm. Now define the vertical play (the most dangerous) . To do this , you must set the rod exactly in the center , it does not touch the cheeks crankshaft .
Then gently try to move the rod up - down . At this stage it does not matter , there is a strong backlash , or barely noticeable , which is barely felt. It was his presence is a cause for replacement. Most of the run- rod crank cheeks can be accepted for play , so it's important to spend some time this operation , each time exposing the rod exactly in the center , and excluding the beating .
Thus we have the basic checks that could indicate a worn crankshaft . However, there is one failure , known as the crankshaft runout . Simply put , this is its curvature . This fault is usually characterized by severe vibration of the shaft and the scooter as a whole. Run-out is checked for a special unit using specific tools , so to determine the exact value in the home is not possible. Axis deviation of 0.05 mm, the maximum allowable . After that, the shaft is subject to equalization or replacement if repair, according to experts, is impossible.
