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Just to be sure, verify the accuracy of the suction gauge. I had a 206 with a long history of premature pump and gyro instrument failures. First thing I did was put a hand-held vacuum pump on the suction gauge. When the hand-held read about 9 inches the suction gauge showed five. Previous mechanics had just cranked up the regulator to compensate for an apparent low vacuum problem. So the vacuum pump had been working it's heart out and the instruments were spinning up like mad.
Most people know to replace the hoses at pump time because of vane debris heading for the vacuum instruments.
Some pumps simply get too hot in particular installations resulting in consistent premature failure. A shroud and cooling duct can sometimes be fitted to eliminate that problem.
Parts to overhaul a tired but not destroyed pump can be bought for between $70-180. Once the pump is on the bench, it doesn't take long at all to overhaul one. A preemptive overhaul at 350 hours might be more convenient than a failure and replacement on the road.
Bawb
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