Master Switch activation not immediate

[SnowJustice]

I am a new Mooney owner (1963 M20C). My plane has about 20 hours since I've become the owner and a March annual. I'll mention a couple of things in the way of background. The flights I've done to date are 6 pattern-work sessions and 3 x-countries. On the 2nd flight I left the lights and pitot heat on a little too long during my walk-around and the the 2017 battery did not start and we had to jump it. The next day it did not start despite a very brief walk-around and it was replaced. Around this time we replaced the red side nav light which was sporadic.

Today I went to do a run up on the plane and flipped the master switch and the ignition did not do anything. Absolutely nothing. So I turned the master off. I thought that was strange, but then I thought "could I have forgotten to push in again? (remembering the shower of sparks concept)" So I tried again and got the same result. I flipped the avionics switch and they did not turn on either. Then I noticed (of course) that none of the instruments was humming or spinning up. Right when I noticed this, everything came on and I was able to start the plane. I did a run up and then shut everything down.

Now I can't say for sure the exact timing between flipping the master and going to start the ignition on the previous 9 flights, and I can't say for sure that the master has come on immediately or after a delay (although I would have imagined my instructor would have noticed something - but to be fair if we were talking thru something during the time between flipping the master and turning the ignition we might not have noticed).

So my question is: is the small amount of seconds (0-20) delay normal? 
Or should I have this checked out immediately? I should mention that I'm handy with electricity/electronics and of course have a mulit-meter.

I'm opting for the latter but want to raise the question in case I'm missing something basic.

Thank you in advance for any information sharing and learning you can impart.

[ShuRugal]

Sounds like a failing master relay. The switch on your panel doesn't energize the panel, it only energizes a relay which energizes the main bus.

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[0TreeLemur]

8 minutes ago, ShuRugal said:

Sounds like a failing master relay. The switch on your panel doesn't energize the panel, it only energizes a relay which energizes the main bus.

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@SnowJustice before replacing the master relay I suggest disassembling, cleaning, and reconnecting all the wire connections to the relay.  Those relays do fail, but more often than not the problem in my experience was corroded connections. 

When you flip the switch do you hear the relay click?   Should be audible without headphones on.   If so, and you have no power, it is either the power connections on the relay or the internal relay contactor.   Clean those connections (big wires) and try again.

If you flip the switch and you do not hear a click, then it is either the power connection to the energizer coil, or the something causing the contactor to bind (unlikely).  Clean the energizer connections (small wires) and try again.

If after that it still doesn't work, then your relay probably needs replacing.

Good luck.

[SnowJustice]

Wow thank you for the quick information! This is gold.
@0TreeLemur I did not hear a click with headphones off.

[MikeOH]

"Wiggle" the master switch while listening for the relay click; if you can get it to click the master is going bad.  If not, as others have suggested, check the wiring to the relay coil.

[A64Pilot]

I’ve had it be the switch, you can tell that with a multimeter by measuring voltage at the relay, probably need either long leads or a helper