Simple Procedures For Checking Shock Absorber
In the following cases, remove the shock absorber from the vehicle and make the checks explained below.
(1) When considerable oil leakage is noticeable.
(2) When excessive vehicle vibration is felt and this vibration does not stop.
A. VISUAL CHECK
Check the shock absorber for the following points:
(a) Dents and scratches on the cylinder.
(b) Damages on the piston rod.
(c) Signs of oil leakages.
(d) Signs of damage on the rubber bushing mounting the shock absorber.
B. CHECKS ON FUNCTION AND FOR ABNORMAL NOISE
Checks for inadequate damping force and abnormal internal noise due to oil leakage can be made through manually operated tests using an equipment as illustrated on the following figure.
Operate the lever quickly 8 to 10 times expanding and compressing the shock absorber. During these pumping operations, there should be a uniform resistance during both expansion and compression without any very soft or very hard spots.
When you change directions and there is a place where you feel no resistance, the shock absorber is faulty and should be exchanged for a new one. On the other hand, if it gets so hard that it refuses to move, this means a faulty shock absorber also. If you can hear noises during your pumping operations, these noises will appear when you are driving also and the shock absorber should be exchanged for a new one.
C. WHEN NO TESTING DEVICE IS AVAILABLE
The shock absorber can be checked to a certain degree by the following methods:
(a) Insert a rod through the lower rubber bushing mount. Step on the rod and keep the shock absorber upright by holding the installation bolt with both hands. Push-pull the shock absorber 8 to 10 times by hand.
(b) When you can feel no resistance, exchange for a new unit. When resistance is felt, the shock absorber is all right. However, this manual operation is actually very slow when compared to actual riding condition shocks and the check itself can only be an incomplete one. The check for noise would be incomplete also.