Hey everyone. Jason
Schappert here of MzeroA.com alongside Zach
with Champion Aerospace, World Famous Russ. He's our director of maintenance here at
MzeroA.com. We're on the topic of preventative maintenance. Let me set
up the scenario and then I will let Russ and Zach kind of take it away from here.
You're doing your engine run up. On the checklist it says
magneto check. So we check the mags and we get, I call it a bad mag, a
bad drop, something along those lines. I was always told we
run it up, we lean it out and magically it fixes it. What's actually
happening in that process? You can speak from not only Champion Aerospace
perspective but both of you are pilots. You're a CFII, MEI. So
we're all talking to pilots, talk to me about spark plugs,
foul plugs, what are we looking for? What's happening? Then can we
clean a gap some and everything else. Yeah certainly. You know it's funny because I came from a pilot
background too and being a pilot, you always just trust the
ignition system is going to work right. And then until you have a fouled plug or something or
a bad mag drop that you realize there are some faults in this system. There are some
things that can go wrong. Well there are things that you can do as
a preventative maintenance standpoint to make sure that your ignition system is always primed and
ready to go. And Champion Aerospace has been in the ignition business
for over 100 years now making spark plugs
and we also do turbine ignition products as well. So we
are die hard fans of ignition. That's all we do is live, breathe and
die ignition. So as far as the spark plug, the spark plug
has been the choice of ignition not only for aircraft
but for automotives for many years. There are differences for the
automotive and the aviation spark plug. But,
one of the faults of the spark plug and especially in regards to aviation,
is that the aviation fuel that we are using is not as clean
as automotive fuel. There's lead
in it. That's why we call it 100 low lead, but there is lead in it. That's why your car uses
unleaded fuel. It's not going to have the same issues. But also
unlike an automotive car, in an airplane you're responsible for controlling
the fuel air mixture right. So you have responsibility for whether that
engine's running hot or cold. You can adjust the mixture and your EGT rises
and falls. Well if you are running it too cold, there's
instances where you can deposit up the spark plug. And that's generally
the primary reason why you are going to get a fouled plug. Well even thing about like, I lean
on taxi. Maybe I'm a little crazy and people debate that all the time,
but I lean on taxi and I don't see as many fouled plugs lets say because of that
lead litterally loading up. Can we look at what a good plug looks
like? What does a really crummy plug look like? What's happening here?
Russ you have some stuff. Yeah we have several different type of plugs here.
We have one here that's lead
build up pretty bad.
We'll demonstrate here in a minute. Well I'm looking at a proper one with nice
gaps and everything else and nothing, porcelains looks good and then you look at something like that.
So we're talking. How does that even fire
in that case? Can it fire or not a 100 percent? It's not going to be 100 percent.
It could be intermittent, it just depends.
You know that's one of the things, sometimes you would have to lean it out and run it up and
try to burn it off. You hope you can burn...that's a lot to burn off. It is.
This is one particular type of spark plug that is just not going to happen.
Are you going to see this more on bottom plugs than top plugs. I mean is that
kind of how that works? I'm not a maintenance expert like you guys. I mean is the lead going to
to the bottom plugs more? It doesn't matter if it's going to be top or bottom
but you will have more problems with the bottom plugs, more so than the top ones. I believe that.
Yeah gravity takes it's part as well in the bottom plugs. Typically what you will find
in them is they are oil fouled. So we've been talking about lead fouling
Champion actually makes this check a plug and it goes through the
six different types of fouling that you can get. So lead is
a big, especially in training aircraft, the 152,
it's a very cold running engine so it gets significant lead deposits.
But there's also worn out conditions which we'll talk about. But
carbon fouling and oil fouling as well. Talking about the bottom plugs
oil fouling is significant. I can only imagine. One great
thing also about the spark plugs, it also tells you the health of your engine.
Really? How so? Because you can tell if you have
a leaking valve or a bad exhaust valve or if you have an oil issue.
If it's burning too much oil. Like this one here, you
can tell that it's burning oil and it's burning hot. Because it's black? It's black from the oil
and then some of the white deposit in lead, will tell that it's burning hot.
Wow. You can tell the health of the engine. We generally
recommend at Champion checking your plugs every 50 hours. So when you bring your aircraft in for an oil change,
it doesn't hurt to pull the plugs out because it's an indicator of what's going on in your engine.
Just like when you pull out your oil filter, you cut it open to see if there's any metal inside,
of it. Same thing with the spark plugs. If there's something going on with the cylinder, if there's
a bad ring and you're starting to get oil leaking into that cylinder, pulling out the spark
plug, you're going to be able to note that right away. And this by the way is preventative
maintenance stuff. Owner operator's can perform this
operation here. So can we get to kind of testing and see what
we can do as far as that goes. Certainly. So a few things I want to reference
our AV6R, a lot of mechanics in the field are familiar with
it. I have a print version, but it's also available online. And this goes through
the entire process for maintaining your spark plugs essentially.
Proper rotation,
which we'll talk about why that's important, but the different types of fouling and how to use our
CT475 Spark Plug Cleaner. So this
cleaner here, it does a few things. At the end of the day
we're going to put a plug in it to make sure that it's sparking. And what we're looking for is
a bright blue continuous spark. It's got to be that. It's got to be blue
and it's got to be continuous. If it's a dirty color, yellow color, or if it's
sparking intermittently, it's a bad plug. And there's lots of different reasons
a plug can go bad. We've talked about fouling. Another instance is
this white ceramic insulator in there. It's ceramic so ceramics
have an ability to shatter or crack. So we always talk about if you drop
a plug, the second place you should drop it is in the trash can because
what happens if you drop the plug, even if you have a hairline crack in the insulator,
that allows the 20,000 volts that are coming off the aircraft magento
to be grounded to the shell. So what this does, is this
under pressure, so you raise it to about 135 PSI.
Insert the spark plug first and this is a high ignition
lead that basically represents the amount of voltage coming off of the magneto.
So you install the plug, you turn up the pressure and you test it
and that's what you're looking for is that bright blue continuous spark. I never realized the ceramic goes
through and through. When you look at a regular plug, you go oh I see it.
I dropped it, oh it doesn't looked cracked, but it's going...I didn't realize that. Exactly.
So don't drop spark plugs. Exactly.
You're dropping 20 dollar bills or more on the ground. That's very, very true.
The other thing the CT475 does is it helps clean the spark plug too.
So if you have an instance where you have a dirty spark plug, you're
going to want to clean it. And sometimes if it's not sparking correct you can clean and get it to work
properly before you put it back in the engine. So this actually on
the underside has an abrasive compound, a sand type compound.
So you install the spark plug and it is pressurized so there would be an
airline hooked up to here. You give it about three seconds of abrasive blast so I'm
going to install the spark plug here, give it the abrasive blast,
and then rotate it around. And it has a clean air blast as well
to clean off the firing end as well. And then retest the plug and it should
be functioning properly. If it doesn't function properly even after cleaning it, that's usually
an indicator that you have a bad cracked ceramic and it's time to replace the plug.
Wow so Russ let's get this thing hooked up and let's do some testing and kind of see it.
Alright, sounds good. So let's go ahead and talk about cleaning
and gaping the spark plug. So it is cleaning and gaping for a reason
The first thing you want to do is properly gap the spark plug.
From the electrical side of it, every time a spark plug
sparks, it takes a little bit of electrical erosion with it.
And so either the center electrode or the ground electrode is going to be
losing some of it's consistency essentially.
And so in order to counteract that, every time the spark plug
opens up, the gap gets wider and takes more voltage and so you're putting more
strain on your ignition system, on your magneto, on your leads. So getting
a gaped properly back to 16,000 to 21,000 is the important step.
So you have a feeler gage here and you are going to check and make sure
that it's set between 16,000 and 21,000.
And any mechanic shop is going to have a feeler gage.
And then once this is gaped properly, we're going to move onto cleaning it.
So we talked about the different types of fouling right and there's carbon fouling
and then there's lead fouling. So lead fouling you are going to want to take care of first. And it's
not generally going to be cleaned out with the abrasive cleaner. It's going to take a little bit more
of an abrasive like a pick. So this pick can come in
and take all of the lead out. You want to be careful not to scratch the ceramic.
but go ahead and take all of the lead out. Interesting.
So once the lead is out, we're ready to clean out and what this abrasive cleaner
is going to do is it's going to take out all of the carbon fouling, all of the deposits that are stuck.
on the ceramic and in the firing end. So a really simple machine to use, you just
want to make sure you have shop air pressure. And you probably know
as I do that there's one of these sitting in a lot of mechanic shops. So if you don't have one
yourself, I'm sure you can find somebody at your local field who has one. So
you take the spark plug, you put it here in the rubber,
and you're going to give it three to five seconds of abrasive blast
and what it's doing is it's taking air pressure and mixing it with sand and then
putting it around the firing end. And you don't want that left in the plug, so you're
going to air blast it as well. So three to five seconds of abrasive blast
and then about double that for air blast. So I'm going to go ahead and demonstrate
and watch as I demonstrate, as I rotate the plug. That's important. You don't want to leave it
stationary. Here comes the abrasive blast.
And now what we're going to do is airblast
it to get all of that deposit out.
And then you just want to inspect and verify. And that's a very clean plug
there I would say. You don't want it to look crystal white.
You aren't trying to make it look like a new plug right. You can over do it and start
affecting the ceramics. So this is a clean plug.
The last step is making sure that it sparks. If you have it gaped and you have it cleaned. What we're going to
do is put it in the spark tester and
it's very important that you use a pressurized spark tester like the CT475
because the plug is going to perform differently
under pressure just like it is in a cylinder right. Good point.
Exactly. The pistons coming up and compressing that air, so it's putting that spark plug
under pressure. You want to make sure it's going to spark under pressure as well.
So I'm going to install the lead here and you're going to take
the pressure gage here and boost it up to 135
PSI. So we're going to turn this on and get it up to 135
PSI. And then run the tester
And again what you're looking for is a bright blue continuous
spark. A dirty yellow spark or an inconsistent spark, if it just sparks
and turns off is a bad plug. Have you ever see
someone take a wire brush to the spark plug?
Yes and that's a good thing to talk about.
because it is a common mistake. It is okay to use a wire
brush to clean off the threads here.
I just took off the testing equipment here. So when you're
installing a new spark plug onto a cylinder, an old spark plug, you're going to put some
kind of anti-seize compound on it. You need to clean that off to put new, fresh
anti-seize compound on it. So it's okay to use a wire brush. The thing you want to
be careful of is you don't turn it into the wire brush. You don't want to start messing with the...so
we are cleaning the threads. Exactly. And very, very important, this is probably
the most common mistake that I see. We will get plugs back that were brand new
and they were sent in under warranty because they installed new plugs and low and behold the engine
was running rough. So I pull the plugs out and I test them on our tester. I have one just
like this and 11 of the 12 plugs work well and one plug
is fouled. And what happens is the anti-seize compound can
leak and bridge the gap here so that you have
conductive material stuck between the two electrodes and that plugs not going to fire. So that's why
the engine was running rough. So when you are installing, very very important, when you are installing a new plug,
with anti-seize compound, you only want to install it from the second thread down.
so it doesn't leak in. Interesting. Very, very cool stuff. Guys I hope you're loving
our new maintenance series. We're going to talk about rotating
plugs in a future video. We're going to talk about magnetos. A lot of
great stuff that is going to be an asset to you all. So listen, hope
you are having a wonderful day. Can't wait to read your comments below this video. Myself,
Zach and Russ will be watching those comments to be able to chime in and help you all.
Enjoy the rest of your day and most importantly remember that a good pilot is
always learning. Have a great day guys. We'll see ya. I wrote the Private
Pilot Blueprint with the intention of if I could do my flight training
over, what I wish someone would have told me. And I want that
book to be yours for free. All I ask is that you pay shipping. Visit
PrivatePilotBlueprint.com to get your free copy.