jjconstant
Well Known Member
I'm trying to chase down an indication problem with my Manifold Pressure. Sometimes it is rock solid and other times it varies by as much as 1.5 inches in cruise. It has always done this, but I'm at the point where I'm going to be more "heads down" in the cockpit under the foggles and I would like to see if I can resolve it.
Previously I noticed that a very small amount of oil leaks into the line, coming out of the restrictor fitting on the #3 cylinder, but I don't know if that would cause the variation. Another thing I'm wondering about is the number of T fittings I have. I've got 1 line coming from the #3 cylinder. 2 PMags are joined by a T and there is a T dividing the line from the PMags and to the gauge.
The only other possibility that I can think of is the baffling that joins the airbox to the cowl. Sometimes after I land I see a bit of a pucker in the baffling. I always assumed that it did that on either start-up or shut-down but I wonder if a little bit of flexibility there might sometimes start to pulse or resonate in flight?
Any other ideas or likely culprits would be appreciated.
Previously I noticed that a very small amount of oil leaks into the line, coming out of the restrictor fitting on the #3 cylinder, but I don't know if that would cause the variation. Another thing I'm wondering about is the number of T fittings I have. I've got 1 line coming from the #3 cylinder. 2 PMags are joined by a T and there is a T dividing the line from the PMags and to the gauge.
The only other possibility that I can think of is the baffling that joins the airbox to the cowl. Sometimes after I land I see a bit of a pucker in the baffling. I always assumed that it did that on either start-up or shut-down but I wonder if a little bit of flexibility there might sometimes start to pulse or resonate in flight?
Any other ideas or likely culprits would be appreciated.
