Manifold Pressure Line Replacement

[Jim Worley]

Has anyone replaced the manifold line from the firewall to the gauge? I am moving my gauge and neither the parts or maintenance manual give any specifics about the line. I need to purchase the materials to make a new, longer line to reach my new gauge position and I have no idea waht to get. Does anyone know if it is possible to replace the metal line with a flexible one? Thanks.

Jim

[skipsouthernsky]

Dear Jim,

It shouldn't be a big problem to replace a MP line behind the instrument panel. From your post I am assuming that you currently have a piece of rigid metal tubing from the firewall to the guage. One question, is your panel mounted on rubber shock mounts or is it rigidly attached to the airframe structure as in the Ron-John's modification? If it is on rubber shock mounts which allow for some slight movement, then a flexible hose would be the best choice since the rigid metal line would have a slight chance of working and cracking over time with movement of the panel. If your panel is rigidly fixed to the airframe, then a rigid metal line would be less costly, more eloquent, and probably last the life of the plane. Of course any line that is made, needs to be pressure tested after fabrication, either by the mechanic that fabricates it or by the facility that manufactures it (even though the line carries very little pressure). I'm assuming that there are existing AN type fittings at the firewall and at the guage to hook to. That way the hose or line can use standard matching AN fittings.

Sincerely,

Skip Dykema