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Topic: FRONT PRESSURE GAUGE READING 155 PSI AND RISING (Read 1169 times) previous topic - next topic

FRONT PRESSURE GAUGE READING 155 PSI AND RISING

The front cockpit air gauge has always read about 10 PSI higher than the rear, but after installing a new Bendix air regulator/governor and air dryer canister on the engine four months ago, the cockpit air gauges read the following maximums:

- 155 PSI Front, and slowly rising, pegged high
- 125 PSI Rear, and steady

Is the front gauge defective?
Is it a coincidence that the front gauge reading has become higher after the governor was replaced?

Re: FRONT PRESSURE GAUGE READING 155 PSI AND RISING

Reply #1 –
I think I would try swapping the air lines at the gauges to see if the readings followed...
Don

Re: FRONT PRESSURE GAUGE READING 155 PSI AND RISING

Reply #2 –
Probably a bad gauge (if mechanical) or bad pressure sender (if electric).  There no way you can have that differential between the front and rear tanks at compressor cut-out.  They are both fed by the wet tank, and all three are at the same pressure the instant the compressor cuts out.

Try swapping air hoses on (mechanical) gauges, or wires on (electric) gauges.  See if the high reading moves to the other gauge.
 

Re: FRONT PRESSURE GAUGE READING 155 PSI AND RISING

Reply #3 –
Just connected another pressure gauge to the auxiliary air outlet connector, used for tire inflation. It confirmed the higher-reading gauge is bad. We are camping at the big Oshkosh airshow, so I guess we'll live with it until we return home. I would regret cracking an air line behind the instrument panel with little resources to fix it.