Arrow Hot Start Problem
I don't have a scanner so gotta type the whole thing. Hope it helps.
Question: (I'll shorten the question to just saying that the guy was having hot start problems real bad )
Answer: Dear Slow
Unbeknownst to many maintnance technicians, Piper ( and to be fair, Cessna, too, although to a lesser degree) installed aluminum wire in many single- and multi-engine airplanes.
Service bulletin 836A addresses this issue and lists virtually every Piper airplane from the E-2/J-2 up through the PA-44 Seminole as being affected. The bulletin calls for inspection of the large diameter load-carrying wires, including the battery to ground; battery to master relay; master relay to starter solenoid; starter solenoid to starter and engine return ground cable (engine to airframe) wires.
Copper wire carries approximately 20 percent more current than aluminum wire of the same gauge. The Service bulletin accounts for this by directing that the aluminum wire be replaced with smaller gauge copper wire.
The biggest problem with aluminum wireing is the formation of corrosion between the wire and the terminals. Corrosion creates a high resistance junction that cuts down on the cable's potential to carry the heavy current loads needed during starting.
Individual copper wires can be produced locally in accordance with the bulletin (provided the proper crimping tool is available), or copper cable kits can be purchased from Bogert Aviation (www.bogert-av.com).
The Bogert kit for your Arrow contains nine new cables; current cost is $381.00. I installed a Bogert cable kigt on my Comanche and have had no starting or electrical problems since.
Just one more note: during my in-shop maintenance career, more than once I found that starting problems were caused by the failure to (re) install the engine-to-airframe ground cable following an engine change; or an accumulation of paint, oil or dirt on the engine and airframe (usually engine mount) grounding surfaces.
Happy flying.
Hope this helps.
Mike
Question: (I'll shorten the question to just saying that the guy was having hot start problems real bad )
Answer: Dear Slow
Unbeknownst to many maintnance technicians, Piper ( and to be fair, Cessna, too, although to a lesser degree) installed aluminum wire in many single- and multi-engine airplanes.
Service bulletin 836A addresses this issue and lists virtually every Piper airplane from the E-2/J-2 up through the PA-44 Seminole as being affected. The bulletin calls for inspection of the large diameter load-carrying wires, including the battery to ground; battery to master relay; master relay to starter solenoid; starter solenoid to starter and engine return ground cable (engine to airframe) wires.
Copper wire carries approximately 20 percent more current than aluminum wire of the same gauge. The Service bulletin accounts for this by directing that the aluminum wire be replaced with smaller gauge copper wire.
The biggest problem with aluminum wireing is the formation of corrosion between the wire and the terminals. Corrosion creates a high resistance junction that cuts down on the cable's potential to carry the heavy current loads needed during starting.
Individual copper wires can be produced locally in accordance with the bulletin (provided the proper crimping tool is available), or copper cable kits can be purchased from Bogert Aviation (www.bogert-av.com).
The Bogert kit for your Arrow contains nine new cables; current cost is $381.00. I installed a Bogert cable kigt on my Comanche and have had no starting or electrical problems since.
Just one more note: during my in-shop maintenance career, more than once I found that starting problems were caused by the failure to (re) install the engine-to-airframe ground cable following an engine change; or an accumulation of paint, oil or dirt on the engine and airframe (usually engine mount) grounding surfaces.
Happy flying.
Hope this helps.
Mike