Manifold gauge leaking down?

jerryab · #1 12-18-2009, 12:47 PM

On a cross country flight this week in my RV6A, I noticed my manifold pressure was down to 15 in, but I was still flying at cruise speed. I added full throttle and it resulted in no increase in mp. It had been fine on my departure. When I returned it was fine on take-off, but leaked down again after 20 minutes. I've recently replace the transducer. This is Van's guage. Any thoughts on where I should look. I've already checked the lines at the connnections. This is an O-320 D1A.

Jerry
N331RA

Steve · #2 12-19-2009, 10:31 AM

My MP gage behaved identically. I could get the gage to go full deflection when I keyed the mike. Then it would go full deflection when I turned on the master switch. Cycle the master and the gage would stay at zero, and never work at all again.
I pulled the whole Vans MP system from the plane and replaced it with an old fashioned mechanical/pneumatic gage and copper tube plumbed directly into #3 cylinder head.