Electrical Problems

[Gord Tessier]

They are an easy fix. There is a micro switch on top of the throttle linkage on both engines. It's attached to a silver roundish cam. Simply undo the little screws and move the switch so it hits the flat spot on the cam at the desired place. Then tighten it down.

[Hyflyer86]

Thanks Gord:

Switches are ok. The warning box is messed up. I am working on it now. Thanks for responding. I appreciate it.

Hyflyer86
Bill

[JamesC]

If the switches are OK then consider thoroughly cleaning up the banana plug type connector in the wiring just before switch. If it is corroded/coated with oxidation then the resistance can be high enough that the gear horn can sound.

[Hyflyer86]

Thanks James:

Good advice. I did look at the connections and they look ok. I pulled the warning box and it has issues that I am fixing at the moment. I still have a popping CB on the "oil dilution" circuit. I have changed the CB to no avail. I can't seem to find the short in that maze of wiring.

Thanks for the help. I really appreciate it.

Bill; Hyflyer86

[DrDave]

On my 67 B model that is the QB1 wire. It comes from a 2 amp breaker. Without the oil dilution system the wire capped off. I believe that breaker also powers some instruments.

Is there anything that doesn't work in the panel?
Do you actually have the oil dilution switch/valve?

This is an easy circuit to trace. The bundle from the circuit breaker panel goes forward and turns around the edge of the lower panel. It joins up with the bundle coming to/from the front engine. The bundle is right behind the lower switch panel. I would start by identifying/tracing the QB1 wire. I don't recall what other wires are hooked to the load side of that breaker. I think it's the engine gauges. It's worth looking close at that area. I've included a pic of the back of my engine inst. panel that I just finished cleaning up the wiring. The spade terminals can get loose and cause problems.

A methodical approach will identify the problem. I'm not excited about just throwing parts at problems like this.

Dave

[Hyflyer86]

Thanks Dave:

On my P model the cb is labeled "oil dil , tach, oat". The tach and oat both work even with the cb popped so I think that only the oil dil is connected. I changed the cb just to eliminate that but no joy. I don't believe that I have oil dil on the plane. I have tried to trace the lone wire from the cb but cant ID it thru he firewall. It has to go to the aux pump and I am looking there now.

I have also jacked the a/c and believe the landing gear switch is faulty. Waiting for switch to arrive. That should fix the gear problem. We are gaining on it. Thanks for the post. Much appreciated.

Hyflyer86
Bill N 86C

[DrDave]

Okay, so someone has gotten creative behind the panel. I would tend to disregard the breaker labeling in this case. The wire is going somewhere. You only have two and a half options for the popping breaker. There is either an excessive load to whatever it's hooked to now or there is an intermittent short. The half option is a bad breaker that trips all by itself. That is a much less common situation. You should also be on the lookout for something that was disconnected and the wire left dangling.

Dave