This issue has been bothering me since a few months now. During light rains, the wipers work fine. However, during a heavy downpour, the wipers would suddenly stop right in the middle of the glass. After that it's tough time driving. Later however, when driving back home say after a day's work, the wipers come alive, but in light rain only. Mechanics cleaned the debris collected below, cleaned the pipes clogged with leaves etc but no good. The wipers run smoothly at designated speeds in dry conditions. This is strange because if the motor was to be the culprit, it wouldn't work even on light rain. Mechanic is certain it is a motor problem. I don't trust them. Someone suggested getting the bushings checked and greased etc. Before I agree to changing the motor, is there anything else to check?

inside motor pins are covered in grease or maybe water, i would open it up and check, i think they are torx screws