This is the back of a current generation Hartzell PG.
The process for converting the ratio between wide deck and narrow deck involves moving the plug between hole A and hole B,
and then adjusting the clocking and Max RPM.
This is the back of a current generation Hartzell PG.
The process for converting the ratio between wide deck and narrow deck involves moving the plug between hole A and hole B,
and then adjusting the clocking and Max RPM.
According to Kevin Ryan, Hartzell tech support ([email protected]), the following is the case:
- The max rpm of the S-1-26 is 2570 rpm.
- The correct governor for the IO-540-D4A5 narrow deck with max rpm 2700 is actually the Hartzell S-1-79.
- Kevin told me that Van's actually does sell this part number...
According to Van's, the Hartzell Governor they sell as "Part Number = PROP GOV HZ IO-390" is Hartzell S-1-79.
Kevin, the same guy you spoke with, is also the same guy who told me that they can be reconfigured to different specs. He is the one who told me about changing which hole the plug is in. That was confirmed to me by Ottosen's propellor who are an authorized Hartzell repair shop and distributor.
From a manufacturing standpoint, it make total sense. You want to design and build core elements as universal as possible with allowances for modifications as necessary.
If you don't have a PG, it makes sense to buy what you need out of the box, but that doesn't mean that you can't convert what you need from what you already have.
As an extreme example, some unique part number codes merely differentiate the color of the paint.