Ignition leads

glenn654 · #1 03-04-2009, 06:09 PM

How would I go about testing ignition leads for conductivity without Hi-$ test equipment? Or is it possible.

Glenn Wilkinson

Mike S · #2 03-04-2009, 06:17 PM

Conductivity usually isnt a problem, leakage is.

Are you in an EAA chapter, someone may have a checker, or check with a local FBO.

Look around the airport for the hanger full of old planes, and "junk". Ask the guy you find in there for a "Megger"

glenn654 · #3 03-04-2009, 09:05 PM

Mike,
I'm no where close to an EAA chapter and at my small airport there are no old planes or "junk" but may be some w/i 100 mi radius......what the heck is a "Megger".

P.S. Thanks for the reply

Glenn Wilkinson

Mike S · #4 03-05-2009, 12:15 AM

The test instrument you are looking for is known as a "Megger", which is the name of the company that produces it.

All the old timers I have ever talked to about ignition wire testing just use the term.

Just for fun, Google it.

MNAv8or · #5 03-05-2009, 12:32 AM

Your local FBO should have the tool to check them. You may have to take your plane to them to borrow the tool, but every shop should be checking for leakage at annuals. I have a box I bought here http://www.aircraft-tool.com/shop/de....aspx?PageNo=1 . If your located close to me, your more then welcome to use it.

CESSNADON · #6 03-05-2009, 03:49 AM

The word Megger is the contraction of the word megohmeter. A megohmeter is used to measure very high resistances. One could use it to check for leakage between the central conductor and the shield of the ignition wires.
The readings will be dependant on the humidity and a humid day could produce erronious results.

glenn654 · #7 03-05-2009, 08:32 PM

Thanks Guys,
I do some homework on the megger and ask around.
And to RV8or...unfortunately I'm way down in Georgia, so I won't get up to MN very soon, but thanks for the offer....

Glenn Wilkinson

robpar · #8 03-06-2009, 03:55 PM

Do you know any Industrial Electricians? I know that they use "meggers" for pretty much the same thing. You might be able to find an electrician with one in your area.

Bob Parry

wv4i · #9 04-03-2009, 07:56 AM

Thanks for ATS cable tester link. I just ordered one. Was on my to do list.

I can attest that if you have a plug or wire failure, it can potentially get very expensive, i.e. must buy a new mag/EI, or worse.

Re the plugs, among all the other physical indicators, if one ohms out much higher than the rest, replace it. Can read about this elsewhere.

And ditto for the wires.

Wires/plugs can go from working to not working without notice. Readings far different from the rest about all the notice you get, if that, before a problem arises.

Dave62 · #10 04-03-2009, 08:20 AM

A word of caution about the ATS tester. It is simple to use but does not hook up as it appears it would. It has two leads out of one side...both heavy gauge...one balck and one red....and then one red lead from the front. Two leeds hook to the battery....looks like it would be the two that come out of the side and are heavy gauge.....not so! The Heavy black lead hooks to the negative of the battery.....along with the long skinney lead from the front which hooks to the positive side of the battery. The other heavy red lead is the lead that hooks to the plug wire. I know of several who purchased this tester and could never get it to work....the reason is becaused it is hooked up wrong. Dont know why they dont include this with the instructions but they do not. There is a note on the skinny long red lead...but I know many who have missed it....including me. Hope this helps.

Dave62...(Swift Driver)