I did some checking on your 919H and I came up with a model number of1691121. This unit is what I am basing my response on. The belt number I came up with is 1713515. This belt is 78.1 inches long and .5 inches wide. I see that this belt is making a 90 degree bend off the front PTO. This is one case where I would say using a nonOEM belt is causing your problem. Most nonOEM belts are made to be used in a straight line with no twists or bends. Add to this you are using a belt that is more than 1 inch shorter than the OEM. Don't know what you paid for your belt, but the price for the OEM belt is only about $27.50, which is relatively cheap for that type of belt. Just my opinion.