Hello, John Talley here with boats.net. Today we're going to be looking at the
charging system on our 2002 Mercury Tracker 40 horsepower. As you can see,
we've been doing quite a bit of work to this particular machine, but now we need to address
a problem on it, so if you're ready let me go grab my multimeter and we'll dive into this project.
So here's our issue: when we were taking this apart, it was more than obvious that
the stator connections to the regulator rectifier had overheated, so i just went ahead and cut them
loose. But what we want to determine now, was this just a bad connection that caused it to overheat,
or is there a problem inside either the regulator rectifier or the stator itself?
So what we're going to do is open this up, take a few measurements, and determine if we can just
put new ends on it or if we need to replace it. Okay, so let's open this up a little bit.
Okay I'll say it's safe to say we can go ahead and cut off this charred connection,
strip it back a little bit where we can take a couple of measurements.
I did the same thing on the stator, and this is a single phase unit
so there's only two wires versus three. We're going to start off with our stator,
and I just want to warn you about this: it is very difficult to measure really low resistance,
and this is one of those cases. So what we're looking for is to make sure that neither one
of these yellow wires are shorted to ground or in this case, the case or the mounting points
of the stator itself. And then we want to look at the resistance going from winding to winding--
or through the windings-- which is because this is only a single phase system and with
that you're going to be looking for something around the 0.1.2 ohm range. You just want to--
do not want a direct short. So let's take a look at each end of the winding going back to ground
make sure it's not shorted and then we'll go across to see what kind of resistance we get.
All right, we're in the mega ohm range that pretty much tells me we're good to go on that. Now let's
check the other side, should be roughly the same thing.
Yes, so now let's take a peek.
So I just want to show you this real quick before we do that.
All right so what we're having to adjust for is just our leads is roughly 0.2, .3 ohms. So
whatever we measure, we have to take that into account to actually get to our zero point.
So I'm betting where it needs to be around half an ohm that would get us in the ballpark.
There it is: 0.5 0.4. So this should be good. Now my preferred test is to do an AC
measurement with the engine running, but that can't happen yet. Now we may go back and do it
later, but for right now just doing a static test? This is about as close as we're going to be able
to get to determine if it's a functioning piece or not. At this point I think it is, so let's go
check the regulator rectifier. And if it checks out, then we'll go ahead and do our connections
and save a whole lot of money with just spending it on the connections and not the actual
components. Now we're going to look at testing the regulator rectifier, and we're going to
do what they call a diode test to see if we can get the diodes to reverse bias or forward bias.
Next, let's set up our voltmeter to perform a diode test, and we want to switch it over to
this symbol, and on my particular meter I need to shift it. Now it's ready to do a diode test.
So now we're going to take our black lead and connect it to the red,
then we're going to take our red lead and go to either one of our
yellow ones. And what we're doing right now is forward biasing the diode,
and we should read them somewhere in between 0.4 and 0.5 volts, which that's what we're getting.
Now next we want to reverse bias to make sure
that it's stopping voltage from passing through. So we're just changing
our polarity. That's what you want to see is an open circuit.
And an open circuit there as well. So, so far she's looking good.
All right, now to test the SCR. We've got one side grounded we're still set to diode, and
now we're going to go to either one of the yellow wires. We're looking for is something around 1.5.
All right guys that is within range, so we're going to go ahead and just
put new connectors on here versus spending a whole lot of money
for another regulator rectifier and the stator itself. So these, we can send back.
Now there's a couple of different ways we can do this. I'm going to go back with replacement parts
from Mercruiser to where this can still be unplugged at a later date if need be.
Now if you're in a pinch, you can use just a butt connector and do a direct connection,
but you're kind of stuck with it at that point. Now if you are going to use a butt connector,
make sure that it is a sealing type that you would use with a heat gun to get it to
encapsulate that connection, because if you use just a regular blue butt connector that's open
on either end? Especially if in our saltwater environment? It's going to corrode. It's not if,
it's when. So this is an option, but I've decided to go back with the kit from Mercruiser that's
going to bring it back to factory standards. Let's make some connections. Do yourself a favor:
make sure you put on the insulator... not that i've ever done that before.
No real magic here, but if you are doing this particular procedure,
might want to invest in a good crimper. You can do it with a standard crimper,
but this makes it look really professional. We're bringing it in there just enough to hold it.
Bringing our wire in, make sure you've got it at the right depth. Now let's go.
Ah, take a look at that.
Nice investment. I'd like to see you pull that off with a pair of these.
Now we have to do is just pull up our insulator.
And she's good to go. Same process for the next one.
Oh yeah, I love these things.
There we go.
Three down, one to go.
The trick to this one is just to twist it as you're pushing it toward the end,
and that lets it ride up over that edge.
There we go.
Well there you go, guys. We were able to save this by just redoing this burned up
connection. The test shows that it should be in good shape. I will go back and verify it,
you know, by doing live readings once the motor is running.
And by going this direction, not having to spend all the money on these two pieces,
it makes me feel a lot better about this rebuild project. Well listen, if you need these parts or
any other parts for your boat, why don't you come see us at boats.net and we get you taken care of.
If you have any questions or comments about this video, leave them in the section below and I'll
do my best to answer. And hey, if you like what you see, go and hit that subscribe button. That
way you can keep up with whatever I'm working on next. We just want to say thank you for shopping
here with us at boats.net, and we will see you in the next video. Y'all have a great day.