[Johnauto]

we have multicam Cnc router nicknamed dinosaur at work and we use a vacuum system to hold the material down, mostly 3/4 plywood. The vacuum system is a Multicam Turbovac 425 that have a 20 hp motor and a roots blower attached by two belts.

For over a year now we've had to replace the belts 4 times and now we are burning up contactors. I suspect it's a mechanic issue here maybe caused by a slight pulley misalignment or some other issue. One thing that gets me is that no matter how long I try to line up the pulleys somehow there is always a slight misalignment. I've tried to line them up before putting the belts on then mark it, loosen it and line it up again but it's always slightly off. Should that happen? Something that gets me also is that the blower pulley chewed into the key a bit to where there is a apace on one side, yet with the belts off it doesn't move at all. How bad is this? My manager told me not to worry about it, but that really concerns me. Besides that I really can't figure anything else out besides a bad bearing which I haven't really found much evidence for besides electrical overload. The motor spins freely without any play and the blower spins freely also.

All this started after we replaced the gear oil in the blower. It gave us issues when it would shut off every 20 minutes. Now we are at the point where it would shut off after an hour and a half of cutting and would continue to shut off in shorter intervals if we didn't give it time. Recently it became hard to start sometimes and then it wouldn't turn on at all. It would just stumble like it was trying to start. We replaced the contactor and overload relay with the same exact parts. It was all fine until a week later the contracts burnt out again.

If anyone has any insight into what we could test or what the problem could be I'd be very grateful. This has had us stumped for a while now.

[ger21]

Sounds like the oil may be the wrong type? Too thick, maybe?

[Johnauto]

Sounds like the oil may be the wrong type? Too thick, maybe?

The oil my manager used is very old (5+ years in a barrel). I suggested maybe we should try a new oil, but nothing ever came of that. Besides the age it was the right type of oil. Would it really cause it to draw that much current? I'm not a professional mechanic, so forgive me for any simple questions.