Hello, Garrett here with Boats.net. Today we're working on the 1999 Yamaha
B90 TLRX. What we're doing to it is actually replacing the water pump. It's
not too tough of a job to do. Just need to tilt the engine up, drop the lower
unit, and pull out the impeller. So let me go grab a couple tools and we can get
started. Okay this job can be a little bit tricky, so I'm gonna rate it as a
skill level two, but it's really not that bad so don't get too scared. Okay, as far
as the tools go, you're gonna need a hammer, a punch, a 3/8 ratchet, a 3/8
extension, a pry bar of some sort, a 12 millimeter deep well socket, a 14
millimeter shallow socket, possibly a 14 millimeter wrench, and lastly a torque
wrench. Now, as far as the parts go, you can check us out at Boats.net. There we
have exploded diagrams that give you a really close up view of how everything
comes apart and more importantly how it goes back together.
So get your parts and tools together and let's turn some wrenches. Okay, first
things first. Let's go ahead and tilt the engine up. Simply just lifting up the
engine and then lowering this lever. Okay now that we've got our engine tilted up,
let's go ahead and start removing the lower unit. Alright, the first thing we're
gonna want to do is actually remove our trim tab, but before we do that it's a
good idea to take your marker and actually just mark you a mark on the trim
tab. That way when we put it all back together we can set it to the
appropriate spot. We're gonna remove this plastic cap and underneath
it is a 12 millimeter bolt that holds the trim tab in place.
Just like that. And if you look underneath the trim tab, there's actually a 12
millimeter bolt that we have to remove as well. Okay,
next up is we have to remove the four 14 millimeter bolts that hold the lower
unit to the engine. When you do this, you want to make sure that you remove three
of them first, leave the fourth one still tight, and
slowly back it off because as you back it off the lower unit it's gonna try to
drop and you don't want it falling on your feet. Plus there's a water pickup
hose that we gotta disconnect as well.
Okay before we completely drop the lower unit down, let's go ahead and disconnect
the water pickup - I'm gonna do that by just cutting off this zip tie. Let's hold
it on.
Just like that. Pay attention-- you can notice that the
lower unit is starting to separate as I back off this last bolt. Now we're gonna
hold it, brace it with our with our leg, and then
gently slide it out. Alright, now I've got the lower unit pulled off let me put it
on my stand over here and then we can start on the water pump. Okay we've got
our lower unit on the stand here. Now we're gonna unbolt the four 12
millimeter bolts that's actually holding the upper water pump housing on. When
you do this you want to make sure and take note that there's two different
lengths of bolts, so make sure you remember where they go back in. Okay remove
our four bolts and then slide our upper cover all the way up. What we're gonna do
now is we're gonna inspect on the inside for any type of damage. And judging by
the looks at this one all the ears are still intact.
This upper housing looks like it's still in great shape. So we should be able to
use this. Alright, next we're gonna remove the cup, and a quick and simple way
to do that is to take your drive shaft, twist it in a clockwise motion as you
lift up on the cup and it'll come off of that simple. Just like that. Alright, the
next thing we want to do is actually remove the impeller itself. To do that, I'm
taking you a little flat-head screwdriver and just gently around the
bottom just kind of pry it up a little by little
until it starts to work its way up. Just
like that. Now that we've got the impeller off, if you take a look here you
notice how there's a tear in this water pump impeller. That's more than likely
the reason why wasn't pumping water, so we're definitely going to replace the
impeller. Next thing we're gonna do is remove our Woodruff key, and we do that
by taking a punch and a hammer and tapping the top end of the Woodruff key
until it just rotates out of the sleeve. Just like that. Alright, now that the
Woodruff keys are out of the way, we can actually begin to remove the plate and
then the gasket beneath it. That way we can check out the condition of the
housing. Okay if you look at the housing you can obviously tell that we replace
this housing. But what you want to look for is a lot of corrosion buildup and these
channels in the housing itself. You also want to inspect for any cracks. If
there's any cracks or if the corrosion is just too bad it's a good idea to go
ahead and replace it. Since we've done that already with this one, I'm not going
to replace it. Alright, the next thing we're gonna do is we're gonna install
our new gasket that came in our water pump kit. And then with the plate, if you
look at the plate here you can tell that these fins are ridged. You want to make
sure that those are facing down when you put it on the engine.
Those are facing down. Next up is the Woodruff key. I'm just putting it inside
the channel like so and just tap it in with a hammer.
We want to make sure that the Woodruff key goes in line with the driveshaft
just like this. Alright next thing to do is actually install our
impeller. And if you look closely at the bottom side of the impeller
there's actually a notch cut out for the Wooduff key to sit down inside of and
directly next to it is a fin. So it's a good idea to keep you-- put your fingers
on that fin so you know where the notch is at when you're putting it on. So it
makes it a lot easier to line them up that way. And before we actually slide it
down on the shaft I'm going to take some Yamaha marine grease and we're gonna
actually put it down the inside of the impeller and it's a good idea to put
some on the shaft itself. And just line up that fin with the Woodruff key
and then slide it on. Just like that. We're gonna do the same thing with the
cup as we did with our impeller. We're gonna coat the inside of the cup with
grease and this cups gonna go on the same way as it came off. What we're gonna do
is we're gonna set it on top of the on top of the impeller, take our driveshaft,
spin it in a clockwise motion, and the impeller or go on just like that. Now the
last thing is the upper water pump housing. Slides on just like that. Now
we're gonna take our new bolts that came in our kit and put the long ones up
front and then our shorter ones in the back.
Okay, when you go to tighten these back down you don't want to over tighten them
because remember this housing is plastic. So just take caution when you go to
tighten them back up because you definitely don't want to crack it.
You just want good and snug. Don't over tighten. Okay, now that we've got the
water pump all assembled, now we need to prep the lower unit for installing it
back on the engine. And we do that by taking our marine grease and putting the
coat on the splines at the end of the drive shaft as well as the shift shaft.
That's going to help us slide everything back together. Okay now that we've got
the lower unit prepped to go back on the motor, I'm going to take one of the lower
unit bolts that I took off, carry it with me, already have it in hand. That way
whenever I line everything up I can go ahead and thread one bolt in, that way
it'll hold it in place for me. Okay now we're going to insert the driveshaft
in first. We're gonna brace it with our leg
and we're gonna make sure we line up the splines with our shift shaft. I'm gonna
take one of our bolts that we took over here with us, go ahead start threading it
in place. Okay now we've got our bolt in place our lower unit's held in place now.
It's time to install the remainder of the lower unit bolts.
Okay, we've got our four bolts in place for the lower unit, now let's go ahead and
torque them down the spec. These bolts need to be torqued down to 29
foot-pounds. Let's don't forget the one that goes underneath the trim tab, and
we're gonna torque it to 29 foot-pounds as well. Okay, next we're gonna take our
trim tab and we're gonna line it up with the marks that we made right before we
took it off. That way it goes back in the same spot. Just like that.
We're gonna take our bolt thread on the trim tab. Also going to torque our
trim tab bolt to 29 foot-pounds as well.
Last thing we have to do is put our cap back on our trim tab bolt. Okay, another
job in the books. Really wasn't that tough, was it? Listen for parts used in this
project and more check us out at Boats.net we can get you taken care of. If you
have any questions or comments, leave them in the section below and I'll do my
best answer. Just want to say thanks for watching, and
we'll see you next time.