Hello, John Talley here with Partzilla.com.
Welcome back to our top end build on our 2009 Yamaha YFZ450R.
As you can tell, I've already got it broken down, so let's head over to the table, look
at the tools and the parts we're going to need to get this put back together, and then
we'll dive into it.
So let's go.
Welcome to the tool bench.
Listen, depending on which episode you're watching right now, I'm going to go over all
of the tools you're going to need to either take it apart or put it back together.
So let's go through it.
On the ratchet side, as always, we're gonna have a 3/8ths and a 1/4 inch.
You're going to have various sockets associated with that ranging from an 8 up to a 17.
The only oddball one is this thin-walled 16.
On the Allen side, you need to go all the way down to a 3 and up to this 14.
On the extensions you want to have varying lengths to get in and around the engine.
Just makes life simpler.
The wrench side?
Really short.
Just a 10 and a 12.
Decent set of side cutters, needlenose pliers, couple of different pick tools, always like
having a little magnet extension as well.
Never hurts to have around.
A couple of standard screwdrivers, flatblade and Phillips, then you also want to have a
good breaker bar.
You also want to have a good torque wrench because it's going to be definitely needed
when we go to put everything back together.
Now, if you would, reference our exploded parts diagram.
That's going to give you a very clear picture of how everything is going to come apart and
more importantly how it's gonna go back together.
So once you've got your tools and your parts together, we can go over there and I can walk
you through it.
So let's go.
Alright guys, before we dive into this, I've been looking at the cylinder that came off
of it, and it doesn't look to be in too terrible condition.
What you are looking for, you still want to see the cross-hatches in there.
And I can still see remnants of it but what you do not want to see are any marks that
are vertical.
Because that means they've been scoring in and erasing where those hatch marks are.
Now, I could probably take this, just re-hone it using a ball-type hone and it only takes
a couple of swipes because unlike older cylinders where you had the aluminum casting and you
had a metal insert or a sleeve, this doesn't have that.
It is raw aluminum that's been plated, and I believe this one is using nickasil.
So if you wear past that nickasil when you're honing it out, it's game over.
It's not gonna seal and it's not gonna do what it's supposed to do.
So all that being said, I'm gonna go ahead and replace mine.
If you feel like you want to try honing yours to bring it back, go for it.
But I'm telling you be very careful and use a very fine grit-- 320, 400, somewhere in
that neighborhood.
So, let me go grab the piston and then I'm going to show you how to place the rings on
it.
What I typically do is go ahead and just mark on the top of the piston where each ring end
gap should be.
That makes it really easy when you're actually putting them together.
Alright, with this being the exhaust side facing forward, this is the intake side.
What you want to do on your very top ring is come off 30 degrees off axis. so you want
the top ring to end up here.
Alright, your second ring you want off-axis almost 180 degrees from the top one, so it's
going to be here.
Alright next is going to be your upper oil ring, which is, I'm going to mark here, which
is 30 degrees off axis.
Then "D" is actually your oil expander ring.
Alright, it is going to be another 15 to 20 degrees off of your top ring, so it's going
to end up there.
And then "E," which is your bottom oil ring, is going to be 30 degrees off axis from the
bottom here.
Alright, before we actually put the wrist pin through there let's go ahead and put one
of our pin circlips in place.
We'll do it on the outside.
What you're wanting to do is you want the end of the clip to end up down in this section.
Right about there will do, and let's just walk it in there.
When you get this last little edge right there, make sure that you don't scratch the piston
on the inside.
There we go.
It's pointing about right here, which is fine.
I just don't want it over in this section.
Now, let's go ahead and put some oil inside of where the wrist pin is going to go.
Now, with that done, we can go ahead and carry the piston over, get it connected to the connector
rod.
At this point, you want to make sure you've still got your towels in place here, because
we're about to put in the other circlip and you do not want it to fall into the bottom
of your engine should you miss.
Before we actually put the rings on, let's go ahead and get our dowels in place as well
as that cylinder base gasket.
Be careful not to push your piston around too much and get it scarred up.
Let's get that lower gasket on.
There she goes.
Now, let's go ahead and start getting our rings on.
We want to start with an oil ring expander, which is going to be "D."
Take a little bit of oil and you just want to wet it all the way around.
just a light coat.
When you're putting this on, you want to make sure that the ends actually butt together,
that you do not want them to overlap like that.
That should do it.
Next we can go for that lower ring, which is going to be "E," but I want to keep my
finger on the end of that oil ring so they don't jump out.
It's okay to do what I call spiral these on, but you don't want to use this technique with
the top two rings.
I'll explain that in a few minutes.
Now we're going to put that there and then gently spiral it around to that lower ring
position.
Like that.
Now, we;re going to bring the upper oil ring over to "C."
Alright, so our oil ring is now together, feels nice and even all the way around.
Alright guys, we've got two rings left.
The darker of the two is going to be your second ring and then this shinier one is going
to be the top.
The top one is thicker than the second, so it wouldn't go in that middle section anyway.
But what you do want to notice is there's a "T" stamped on each one.
You want to make sure that faces up.
Just take a little dab of oil, coat it all the way around.
This is going to be our "B" ring, and when you're doing this you want to pull it out
evenly and don't let it bend one way or another and then drop it in.
There it is, just bring it around to "B" without disturbing the oil ring.
Same thing for the top ring, "A." Make sure you've got your "T" facing up.
Put a thin layer of oil all the way way around it.
And now we're going to turn it, make sure it doesn't bother the other ring and bring
it around to "A." Now take a little bit more oil and put it
on the skirts on either side of the piston.
Now, it doesn't matter if you're installing a new cylinder or one you just honed, but
you want to make very, very sure that you get this clean.
So what I'm going to do is spray it down with a little bit of parts cleaner.
Then get all of that wiped out because you want to make sure there's no deposits.
When they ship them out they typically have a coating in there, so I'll bet you when I
pull this out it's going to have some of that sediment on there.
And it does.
See?
That we did not want on our brand new piston and rings.
So, with that cleaned up, let's go ahead and get some oil in the cylinder.
Just a light coating because we actually do want the rings to bite into the surface so
that they seat properly.
Alright, let's see if we can get our cylinder back on.
What we're going to do is pass this magnet through, pick up the chain, hold it out of
the way as we bring the cylinder back down on it.
Push our piston rings in from either side, one at a time, and then kinda walk the cylinder
down on it.
It's just a matter of me getting everything in the right position and walking it down
like that.
There we go.
Now, lift up our chain, finish walking it down.
Alright, with that in place, let's go ahead and put it in that singe bolt over here.
You want to be careful here if your machine is still dirty that you don't want to knock
anything off the frame rails or those cross members that may have dirt on it and they
can fall in the engine.
And that bolt's going to be torqued to 7 foot-pounds.
Now, let's go ahead and put in our chain guide.
My front one was a little bit worn, so I decided to go ahead and replace it.
Put a little oil the length of it, lift up our chain, and go ahead and get her in place.
Now, let's go ahead and get our dowel pins pushed in and then we can put in our head
gasket.
Alright, she's in place.
Now, let's go ahead and bring our head down and we're going to bring the chain up through.
Now I had already taken some of that parts cleaner and just a really soft brush and cleaned
out the combustion chamber.
It's ready to go.
I have not disturbed where my valve tappets and more importantly the shims were when it
was taken apart.
So they're going to be going back in the same location.
But just in case one of them or two of them fell out, I went ahead and numbered them.
That was just a precaution.
Looks like she's sitting flush.
Let's go ahead and get these other two 8mm on this side in place.
Same 7 foot-pounds.
And then we'll put in the head bolts and get those torqued down.
Alright guys, Yamaha has an interesting torque sequence for this particular model.
What we're going to do is put a little bit of grease now that I've got the bolts cleaned
up around this washer.
Remember that's just on the washers.
That's the only place we want it.
Gonna drop all four of them in, and we're going to take them down in a sequence to 22
foot-pounds.
The sequence is 1, 2, 3, and 4.
At that point, I'm going to relieve tension, make them loose again.
One, two, three, and four.
Then take them back down in the same sequence to 14 foot-pounds.
Two, three, and four.
At that point, we do the sequence again, but we're going to turn them 90 degrees.
Here is where if you either need degree wheel or to mark your bolts with just a black marker.
This particular torque wrench I have it actually calculates angles.
So I'm going to use it to do it.
And then when we're done with that, we're going to do the same sequence one more time
90 degrees.
interesting concept, huh?
Alright, with all that jostling around I guarantee you our crankshaft is no longer at top dead
center, so let's get that reset, leave a wrench on it to keep it in place, hold it still,
and then we'll start working on the cam timing.
It is maybe two or three degrees off.
Alright, we're just going to leave that hanging right there.
So now, let's go ahead and coat both the buckets and the surfaces of the cam rods on with a
little but of assembly lube.
Then we're going to carry the cams over.
Tell you what: let's add a little bit more at least to the lobes because I do not want
this thing starving at first start.
Alright, if you were watching the video when we took it apart, the way we want these to
end up -- the lobes to be facing up and then this little divot right here is going to be
even with the edge of the top of the head.
Not this one, the one down here.
This is going to signify that you are at the top dead center of the compression stroke.
Same thing over here.
The divot that you're going to want to be in line is that one right there.
So when we get them in this position, it's going to be timed correctly.
Alright, let's start wiggling them in there.
We'll start with the exhaust first, because it actually pulls against the front of the
engine which is the fixed chain guide.
That's looking good.
Let's verify it down on the crankshaft.
Make sure we're still on our mark.
Remember it's the single mark, not the double.
Yep, we are there, so this is what we were looking for like I showed you on the bench.
Dot, dot, dot, and the lobes are up.
So, little bit more assembly lube.
Let's go ahead and get those caps on.
Get your clip and put it in that little groove on the bearing.
Go ahead and do the exhaust first.
That feels right.
Let's go ahead and do the intake as well.
Alright, that's in place.
Got our dowels lined up, it's holding on to that clip, timing still looks good.
Let's go ahead and get these bolts in.
May want to put a little bit of oil on the threads.
We're going to take these to seven foot pounds.
One, two, three, four.
This one is going to be one, two, three, four, five, six.
Yep, we're good.
Alright, next, let's get our chain tensioner ready to go.
What we have here is remove this bolt, get it out of the way.
Got our new gasket that's going to be going in, and you'll notice there are two bolts
that you took out.
I hope you paid attention, because if the engine is facing this direction, the inside
bolt is the one with this little copper washer.
The one on the outside?
That doesn't have one.
Once you've got that in place and ready to go, you need to go ahead and reset the tensioner
because you can't push it back in right now.
The reason for taking out that bolt is just take a flat-blade screwdriver, and then we
want to screw it all the way back in.
And it'll have a small section to where it'll latch.
You even so much as breathe on it it's going to pop loose.
Other thing you want to make sure of?
This little stamp right here that says "up," so of course we want that facing up.
So we've got our outside bolt, we've got our inside bolt, we've got our new washer, try
not to bump anything.
And now, we're going to go mount it to the bike.
I feel like I'm carrying a bomb over here.
Once we get at least one of these mounting bolts all the way down without it releasing,
we've won the battle.
Screw it all the way down.
And then we're going to reach in there and just tap that bolt on the inside where that
adjustment screw on the inside?
And that'll release the tension and it's going to push against the chain.
Last but not least, don't forget this little end cap bolt.
Alright, let's get our valve cover ready to roll.
We're putting in a new gasket and we're also replacing these two washer that are up top
cause they're all made out of rubber, and rubber as you know after a while gets hard
and then it cracks and fails.
Notice that this piece right here, we actually need to cut it out.
It is not supposed to stay on there.
What Yamaha also wants you to do is use a thin layer of Yamabond 1215 or equivalent
all the way around on this surface and then once we set that in there, then we're going
to put it on the lobes that go down to the head on the other surface.
So we're just going to put a thin layer.
It's not going to take much.
Now, let's go ahead and set this in place.
Now we're going to go over these two half-moons.
Alright, we're all gooped up, let's get her back in there.
And now we've got our two new little washer -slash- seals going up top.
Tighten these down until they bottom out.
You'll feel it when it bottoms.
There.
Alright next, let's go ahead and get our crankshaft cover in that inspection hold for the timing,
and make sure that you're not missing your O-rings on either one.
Alright, the small one's a 6, and the larger one is a 14.
Now let's get that spark plug in.
Want to give you a little bit of advice that I've gotten mainly from the personal watercraft
world.
These spark plugs are notoriously thin where the threads go into the base of the spark
plug.
This one came out, but I want you to look at all the corrosion there that was starting
to build up.
Now what was in danger of happening?
Snap.
Threads stay in, top part comes out.
Then guess what?
You're having to pull this all the way apart.
So long story short, I always put a little bit of anti-seize on the threads before I
put them in there.
Now also remember you have to have a thin wall 16 to get down into the head to tighten
it back down.
And now we want to torque that to 9 foot-pounds.
Well alright guys, that pretty much finishes up the top end engine build, but there's a
lot left to do.
But we're gonna carry that over into the next video.
What all is going to be entailed?
Well we're going to be dealing with the intake, the exhaust, the cooling system, getting it
refilled with oil, getting the gas tank back on it, get all the plastic put back together
and then fire it up for the first time.
Well listen, we do want to say thank you for shopping here with us at Partzilla.com.
We really enjoy doing what we do and making your life easier showing you how to do these
different projects.
So if you like seeing me work on these machines, why don't you subscribe to our channel, that
way you'll know and you'll be ale to see what I'm up to next.
So until next time we just want to say thank you and we will see you in the next video.