Poor craking and starting performance on Piper Aircraft

Poor Starting Performance of Piper Aircraft

I became an aircraft mechanic in 1975. I worked for several FBO’s before I put my name over the door in 1983 and started Bogert Aviation Inc. The FBO’s that I worked for rented Piper Cherokee and Archer aircraft. They chronically had poor starting performance. Often, maintenance personnel would have to plug in the ground power unit to get them started. I noticed that we never had to do that with the Cessna aircraft we rented. What was the difference?

After I started Bogert Aviation Inc. one of my customers owned a PA34 Senica and it always needed a jump to get it started. That was bad enough, but after his engines were replaced, I could not get one engine to crank, even with ground power.

At first, I thought that we may have had a defective starter, so I swapped them. No change. I got my voltmeter out and I discovered that I only had 2 volts at the left starter. After a bit more investigation, I discovered that the issue was voltage drop across all the cables in the starting circuit. This was the first time I realized that the battery and starter cables were made of aluminum.

We replaced his cables with copper cables and the difference was amazing. He joked that he could taxi using just the starters. That got me thinking that perhaps all those other Piper Aircraft had the same underlying issue, copper cables.

The Bogert Aviation STC, replacing aluminum cables with copper cables covers most all the pipers including the short wing PA22, the Comanche PA24, all PA28, PA32 and the twins.

If you are having issues with slow cranking during starting or going through batteries more often than you should, you may need to replace the aluminum cables with the Bogert Aviation copper cables made for your airplane.