I've started to install the various sensors for my G3X system upgrade on my flying RV-8A with a O360-A1A. The original builder had done some things with the old sensors that I've discovered is not the current practice, so I want to update their installation. And the G3X system adds a fuel flow and MAP sensor that adds functions new to the plane.
First the pressure sensors. The fuel and oil pressure sensors are mounted directly to the mech pump in the case of the fuel sensor, and the oil pressure sensor to a NPT tube tapped into the block over the right mag and terminated with a tee to add a port for the Hobbs switch. Currently, there is no MAP sensor mounted. I've read that engine vibration is not good for sensors mounted to the engine, and current practice mounts them to the firewall via a manifold or Adel clamps, with hoses spanning the distance from the port to the sensor. Questions: what types of hoses should I use for the various sensors, and recommendations for the pressure manifold should I decide to go that route vs. Adel clamps.
The oil temp sensor probe supplied with the G3X seems to be significantly longer than the temp sensor it replaces. The new one fits however - are there any issues with using the longer probe?
Magneto RPM pickup. There is basically only a 1" clearance on my plane to install this sensor. I'll have to remove the mag to get it in, and even installed, the cable will be jammed up against the block. I am concerned that this will rub and eventually short the conductors. Is this really a problem, or am I stressing over a non-issue? The original RPM sensor ran off the tach port. Should I consider using a UMA tach sensor instead?
The Red Cube. I've read through the installation history of this sensor in these forums, and it seems that the best current practice is to mount it either free floating or secured to the engine between the mech fuel pump and the carb. Mounting to firewall is not recommended because it is in a different vibration plane than the engine. I would love to mount it in the cabin between the selector and the electric fuel pump, but the manufacturer seems not to advise this. Comments?
Finally, is there any limitation running / clamping K type thermocouple wire near or touching spark plug wire?
Sorry for the long post... Thanks!
First the pressure sensors. The fuel and oil pressure sensors are mounted directly to the mech pump in the case of the fuel sensor, and the oil pressure sensor to a NPT tube tapped into the block over the right mag and terminated with a tee to add a port for the Hobbs switch. Currently, there is no MAP sensor mounted. I've read that engine vibration is not good for sensors mounted to the engine, and current practice mounts them to the firewall via a manifold or Adel clamps, with hoses spanning the distance from the port to the sensor. Questions: what types of hoses should I use for the various sensors, and recommendations for the pressure manifold should I decide to go that route vs. Adel clamps.
The oil temp sensor probe supplied with the G3X seems to be significantly longer than the temp sensor it replaces. The new one fits however - are there any issues with using the longer probe?
Magneto RPM pickup. There is basically only a 1" clearance on my plane to install this sensor. I'll have to remove the mag to get it in, and even installed, the cable will be jammed up against the block. I am concerned that this will rub and eventually short the conductors. Is this really a problem, or am I stressing over a non-issue? The original RPM sensor ran off the tach port. Should I consider using a UMA tach sensor instead?
The Red Cube. I've read through the installation history of this sensor in these forums, and it seems that the best current practice is to mount it either free floating or secured to the engine between the mech fuel pump and the carb. Mounting to firewall is not recommended because it is in a different vibration plane than the engine. I would love to mount it in the cabin between the selector and the electric fuel pump, but the manufacturer seems not to advise this. Comments?
Finally, is there any limitation running / clamping K type thermocouple wire near or touching spark plug wire?
Sorry for the long post... Thanks!
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