Emu563

I have a built-in Beam 284 with 14" canister. The suction seems less than average. I suspect that the permanent filter may be partially and permanently clogged. The unit is vented to the outdoors. I am wondering if the unit can be run for an extended period without a filter, thus sending fine dust outside through the exhust. Will this damage the motor? (It is a two-stage aluminum motor with tangential bi-pass.) I have also heard about a 'screen' that can be used in such cases to remove large particles but have never found one advertized on the internet. Thanks all in advance for your help.