Hello, John Talley here with partzilla.com.
well guess what we have here: a 2012 Polaris RZR 900XP.
This one is going to be an interesting build.
So, what's going on with this one?
Well, somebody else had modified this engine pretty heavy and they did not even come close
to doing it right.
So what are we going to have to do?
We're going to have to pull it back out, break it down, and try to to repair all the mistakes
they made.
This is going to be a pretty involved build, so if you need to build your XP engine, this
is the video to watch.
So, go bring over an entire toolbox, and we'll get started.
Alright guys, so here we are at the teardown bench.
So what's the first steps?
Well, we want to get all these hoses off, get the starter off, go ahead and get this
outer cover off, and then we'll bring it around to top-dead-center, take a look at the cam
positioning to make sure it's on the compression stroke, and then we're going to start breaking
it down.
Let's start by getting that thermostat housing out of the way.
I've said it several times and I'll say it one more: I love these things for taking things
apart, do not use them to put things together.
It'll be painful if you strip something out especially on the inside of an engine.
Next we're just going to pull that hose right here.
Next let's go ahead and attack it from this side.
Get the water pump and these different fittings that go into the block.
What I usually do is with my bolt bags, I usually just group all the bolts together
for whatever particular system I'm working on and then tag it and leave it with the actual
hoses or whatever part I'm taking off.
I was afraid of that.
She had rounded.
We're going to have to get creative.
What we're going to do is go up a size.
We'll end up having to replace this particular bolt. and it's actually not a metric.
This is actually a standard size 7/32, and what I'm going to do is actually beat it in
there and hopefully it'll cut those corners or those edges and that will allow me to take
it out.
Voila.
Like I said, the fun part now: getting that out.
what am I going to do?
Go over to the vice, clamp down on it because I'm going to replace that anyway, and knock
it off.
Alright, we'll just take off this whole big spider web of stuff.
We're going to take off the oil pressure sensor here.
This is actually an aftermarket piece.
And then we'll get this stator cover off.
Then after that we'll pull the starter.
So, let's go ahead and get this out of the way.
Alright, let's go ahead and get this starter out of the way before we pull that outer cover.
Alright, let's get that stator cover off.
As you can tell the magnets are trying to hold it in place.
Don't pinch your fingers doing this.
There.
Strong little boogers.
Alright, let's get these plugs out.
The one I took out on this end?
the gap was on a zero.
That may yield some interesting reasons on the inside.
Alright they told me this engine was really, really hurt, so with the plugs out of it let's
see if I can even turn it over.
Yep, she is locked all the way down.
So, let's go ahead and get the valve cover off and we're supposed to bring up the cams
to top-dead-center.
Obviously that's not going to happen so we're just going to have to take it apart where
it sits.
These are just Torx bits.
Make sure you don't try to cram a regular Allen in there.
She's actually really close to top-dead-center.
Because we wanted both of these cam lobes to be in the up position.
Let's go ahead and get the tensioner out of there, then we'll get the sprockets off.
Then we can get the cam out.
Oh boy look at this: yeah, they didn't do a great job assembling this.
That bolt has almost worked its way out.
The cams are very hard, but because they're hard they're also very, very brittle, so that
means they break easily.
Yeah, there we go.
Alright, we're going all the way down to the crank so I'm not going to worry about holding
that chain up.
A little bit of scoring here.
Nothing horrible, so I don't think it was oil starvation that got this.
My theory is that the wrong sized main bearings are in here, and that's what caused it to
seize up.
But we won't know that until we pull the bottom end apart.
Let's go ahead and get the tappets out.
Tell you what: we're going to go ahead and take these shims out because chances are I'll
end up dropping one and won't be able to find it.
Alright guys, let's go ahead and get this head off.
There are six main bolts up top, and you've got these two little small ones on the side.
The ones up top we want to take them off in eighth-inch turns, and you want to do it in
the following pattern: one, two, three, four, five, six.
And keep rotating around until they're all loose and then you can go on and go ahead
and remove the head.
Alright, let's get this head tapped off.
Keep in mind the head is the only thing holding the cylinder on it right now.
There we go.
Alright, the head actually looked to be in pretty good shape, just my initial looking
it over.
So we want to keep it all covered up, keeping any debris out of it.
Alright next, let's go ahead and get this flywheel off so we can go ahead and get these
chain guides out of the way.
To get that one out we need to go ahead and pull that gear off.
Don't lose that washer.
Alright, let's take that bottom pan off and take a look up in there.
Now I honestly don't know what's causing or what it's hitting but this is going to be
interesting.
Alright.
Oooooh.
See all that?
That is not natural.
We have a bunch of ground up metal now.
From where?
So, we're going to keep going.
Alright guys, let's go ahead and get this oil pump out of the way, then I'm going to
rotate the engine down and I'm going to go ahead and get what this is loosely called
a motor mount out of the way.
That way we can pull all the bolts and actually split the cases and take a look at those bearings
on the inside.
Alright, once you get those three bolts out that are holding in the oil pump, you want
to get the dowels out using either a magnet or needlenose pair of pliers.
Once you get those up and out of the way, then you can tilt her around and get your
chain off.
Otherwise, it won't come out of there 'til you get those dowels out.
Let's get those through-bolts out of that motor mount.
Remember you have to hold that lock-nut still while we're doing this.
Alright, since she's already in this position, let's go ahead and get all these case half
bolts pulled.
Flip her up on the top and then get the bottom bolts pulled where we can split the cases.
I'm sure there's a more particular sequence than
what I'm doing.
Basically just working around the outside-- or from the inside out.
All fun and games until you go to put it back together.
Alright.
Alright, the crank shaft bearings look okay, so that's where I think our problem is going
to be: right in there.
Oh yeah.
Ouch.
There we found our culprit.
So, was that incorrect sizing?
Or oil starvation through the crankshaft itself?
That I can't answer just yet.
Let's go ahead and pull that other one and see if it got both of them.
So that's the way it's supposed to look like.
Not like that.
Wow.
Look how much wider it is.
Especially the other end.
See this distance right here?
How close that tolerance is side-to-side?
Now, look at this one.
It has eaten up this crankshaft.
I don't think we can save the crank.
Well alright guys, there is our smoking gun.
Was it oil starvation?
I don't think so.
If a passage was stopped up somewhere it probably would have gotten both rod bearings.
So what are we going to do?
Well, we're going to go ahead and order a new crankshaft.
We'll go ahead and order the bearings that are going to be required.
And we're going to get the whole set and we'll go through the sizing procedure because I
think that's what happened here: he put in the wrong size, the tolerance on it was incorrect,
and it just ground it up and then deformed it.
Another thing I'm going to go ahead and do is replace the head on this unit because I
know that it has been modified and shaved down and you know on those spark plugs, on
one of those tips had been bent?
My theory is that it is so close that the piston is actually hitting it and causing
it to bend the spark plug so we're going to go ahead and replace that as well.
So what happens next?
Well, I'm going to head back to my desk, get on partzilla.com and order a bunch of parts
and then we can start getting this thing put back together.
So until then, we just want to say thanks for watching, and we'll see you in the next
segment.