We recently purchased a StyleCNC router with vacuum table and it came with two generic vacuum pumps which do a good job at holding down a solid 4x8 sheet but doesn't really hold anything down after it's been cut. When the pump runs it is exhausting hot air back into our warehouse and it smells like a car exhaust. Although I'm told by the company that it does not emit any harmful gases, it sure does smell like a car exhaust and we are concerned with the fumes. Are vacuum pumps suppose to emit fumes like this? It smells like burning oil and we are having to leave the garage bay fully open for ventilation when using our machine.