A Problem With My CR250 Engine Build!


what up everyone it is the day we’ve all
been waiting for time to start putting the cr250 engine back together you guys
know how excited I am so I’m not gonna waste any time just gonna jump headfirst
right into this project step one is the press these bearings and seals into the
crank cases all of these bearings and seals were part of an engine rebuild kit
that rent rabbits sent over so big thank you to those guys an easy way to pop the
bearings into the crank cases is first gonna be to cool down the bearings in a
freezer for a few hours or even overnight and then you want to heat up
the cases either in an oven or a barbecue grill you want to heat up the
entire crank case and not just the area around where that bearing sits that
could warp the crank case so how this works is when things are cooled down
they’ll contract or shrink and then when things are heated up they’ll expand so
that will allow the bearings is slide into the crank cases that much easier
and if we need any extra help we’ll be using a hydraulic press here to heat up
the crank cases I’ll be using this oven that I use for powder coating as well I
wouldn’t recommend using your household oven that you’re gonna be cooking food
in there could be some contaminants coming from the crank case so I would
rather just play it safe you could also use a barbecue grill like I mentioned
earlier so I’ve got the oven heated up to 250 I’m just gonna run the crank case
through there for 30 minutes and it should be ready to go
also got some tinfoil laid down to protect the crank case too and then to
pull the case out of the oven of course you’re gonna want to wear a thick set of
gloves here because it’s gonna be pretty hot I’ll just be using a set of worn-out
scotch-brite pads I use that stuff for everything and as soon as you pull the
case out of the oven and the bearings out of the freezer you gotta pop those
bearings into place right away can’t let things cool off or heat up so the
bearing should slide right into the crank case without any hammering
required I’m gonna start with the main bearing here so it shouldn’t matter
which way the bearings go in but the old bearings came out with the writing on
the inside the crank case here so I’m gonna install it the same way and one
thing I’ve heard about but I haven’t tried is to cool off the bearing even
more people have been using a electronics
duster so it’s like compressed gas so you flip over the can and spray the
bearing with the can and that should cool down the bearing even more before
dropping it right into the crankcase so I’m gonna give that a shot right now so
I’ve got the bearing in about 90% of the way and I really don’t want to hammer on
it so I’m gonna use the press to push it in the rest of the way so whenever
you’re installing a bearing you always want to push on the outside race of the
bearing not the inner race and I’ve actually got this part from a crankshaft
installer tool that I’ll be using later on in the video and it fits perfectly on
top the bearing here so this will work great to press that bearing in the rest
of the way just gonna line everything up here on the press should be good to
start pumping it down ideally you shouldn’t need to use the
press to push in the bearings but this one it went in most of the way and it
didn’t really take a whole lot of force to get it seated so wasn’t that big of
an issue but for the rest of them I’m hoping they go in without any problems
at all once again just gonna slide in these bearings with the lettering facing
out towards the inside of the crankcase one thing to keep in mind if you have a
bearing that uses a retaining clip like this one right here then there’s gonna
be a lip on the bearing here and you want that lip facing out towards the
retaining clip with this bearing the lettering is actually facing the
opposite way of what it should be installed so that could throw you off
but you definitely want to make 100% sure that the lip is facing the correct
way the bearings on this side went in pretty good for the most part but on the
right case I’m gonna heat it up to 350 instead just get it a little bit warmer
one thing I’ve heard that works pretty good too is using dry ice to cool down
the bearings that’ll get them a lot colder than the freezer would but
unfortunately I don’t have any dry ice on hand at the moment as you can imagine
when you have something steel in the freezer and you pull it out and heat it
up it’s gonna have some condensation so I’m gonna squirt down these bearings
with some maxima and ppl to prevent them from rusting the bearings on this case definitely
went in a lot easier so I have the case in the oven at 350 for 30 minutes and
then hose down the bearings with the air duster upside down to cool down the
bearings of amore and that seemed to be the ticket the bearings just slid right
into place now I’ve got some bearing retainers and some seals to install so
this stuff is pretty straightforward definitely want to use some assembly
Lube for the seals I’ll be using maximum assembly Lube for that and for the
bearing retainer bolts definitely want to throw some Loctite on those threads for the crank seals I’m just pressing
them in by hand and tell their about level with a case surface then I’m using
a socket or something like this to push the seal in all the way until it’s flat
with a case and you definitely want to make sure it’s 100% level you don’t want
it cock to the side at all actually I was watching some older video of when I
popped these old seals out and it looks like the previous seal was actually in a
little bit farther so I’m just gonna press this seal in just a tad bit more
to match at this point I’ve got all the bearings
and seals taken care of if it’s time to start filling up these cases the first
step is gonna be pressing this Hot Rods crank into the right crank case so for
the most part it’s pretty safe pressing the crank into the main bearing without
using any heat or cooling techniques however I’m gonna apply a little bit of
heat to help things out so I can either heat up the main bearing or cool down
the crankshaft and it’s usually not a good idea to heat up the main bearing
especially with a seal on the other side but what I’ve got here is a little safer
method I’ve got a socket that fits somewhat tight inside the bearing it’s
the closest one I could find so I’m gonna heat up the socket slide it in and
that will warm up the inside race of the bearing and allow the crankshaft to
slide in a little bit easier that actually worked out a lot better
than I was thinking so I wanted the need to use the crankshaft puller kind of a
bummer haven’t even got to try the thing out yet one thing I didn’t mention is
it’s a good idea to put some premix or assembly Lube into that main bearing
before you slide the crank in so far the hot rods crank and the bearings and
seals have all checked out fine everything has gone together pretty
smoothly and now this is really what I’ve been looking forward to getting
this thing up on the engine stand and starting the building process so
basically I’m just gonna slide these studs through the engine mounting holes
and fasten it to the stand using the wing nuts so now I’ve got the crankcase secured in
a stand just gonna test this thing out and figure out what position I want to
work in probably right about there or even flat I think this would be a little
better position that way have a better angle of a slide in the transmission
shafts ship drum shift forks and all that jazz
you guys have to go check out these engine stands made by the healer
concepts coolest thing ever if you’re gonna be working on the engine so
they’re available over at nihilo concepts com
I’ll also put the link down below before we get started with assembling the
transmission I’m gonna squirt some assembly Lube into these bearings and
the purpose of this is to prevent damage when the engine is first started up so
when you build an engine and you add in oil the oil is not going to be
completely circulated throughout the engine until a few seconds after the
initial startup so that’s where the assembly Lube comes into place it’ll
protect those bearings and surfaces that may not have oil in them at the initial
startup as you can see there is a lot of parts to the transmission so you want to
make sure you’ve got everything there before you start the assembly process so
what you can do is head over to an OEM parts supplier like Rocky Mountain for
example pull up their fish or the parse diagram print out the diagram for the
transmission or the shifting components and you’ll have everything there to
check over to make sure you’ve got all the washers pins spacers gears all that
I might as well just show you guys firsthand so I’m over on rocky mountains
website and I’m gonna pull up om parts right here I’ve already got motorcycle
2003 which is the year of this bike all that selected I’m just gonna find cr250
and then pull up the transmission diagram gonna be down here at the bottom
so it’s got a nice breakdown of all the gears shafts spacers washers and all
that thatwe can check over everything on the transmission make sure it’s all
there and by the way if you guys are in need of parts definitely check out Rocky
Mountain atv/mc they’ve got everything you’d ever need om or aftermarket so I’m
just gonna print out this diagram here and I should be in business alright I’m
gonna give you a little demonstration of how it would check over each
transmission shaft so we’ve got the main shaft here and it’s all broken down here
on the diagram at the very end is a washer which you can see is on there and
then a gear you got a gear here then another washer in between gonna pull
that apart yep there is a washer in there and then a gear after that and
then a bushing of some sort and then a washer or two washers and kind of see oh
that’s actually a clip yeah that’s the circlip in there so you can kind of pull
things apart take a look at it make sure it’s all there and then a another gear
you’re at the end and then in between is another let’s see that looks like a
circlet and then a splined washer as well follow it up with a gear so I mean
you could pull it all apart check it all out make sure it’s all there because
having all those washers and all those clips in there is pretty critical but
definitely doesn’t hurt to go through and check it all while you have the
engine completely apart so the assembly process is up next some of you guys
might notice that this transmission looks a little bit different so it’s
actually been polished out using a process called isotropic finishing so
this is gonna make the transmission work a whole lot smoother and there’s many
other benefits too so if you guys are interested in getting your transmission
done definitely go check out trick engineering we’ll get you all set up
alright enough talking let’s start putting things together so the
transmission gears to line them up you just mesh these gears together well
so you can see they all line up and they’re gonna slide the shafts through
the bearings in the crankcase I think it’s gonna be easier to have the
crankcase more upright when you’re sliding in the transmission shafts that
way you don’t have to hold the washers into place and the gears don’t start
sliding on the shaft give this a shot here so next up is installing the shift
Forks and the shift drum so I prefer to go piece by piece with this stuff I know
some people like to line up the transmission shafts with the forks and
the drum and slide it in as a set but I just like to go piece by piece to make
sure everything is together correctly there really is no perfect way to do it
so for this step it’s gonna be easiest with the engine laying flat that way we
can get at these transfer gears here and slide the shift Forks into that position
all right we’ve got a shift fork set with two on the pin and then this one
just has one so we’re gonna take a look at these transmission shafts and the
main shaft just has one spot for a shift work while the counter shaft has two one
at the bottom and one farther up so of course the pin with two forks is gonna
go on to the counter shaft so it’s really not too complicated the fork just
slides right into that little slot I might have to pull up on the gear to get
it in widened in just like that and the pin is gonna face towards where the drum
sits we’re just gonna leave the pin out of the equation for now that goes in a
little bit later so we’ve got to shift Forks here for the counter shaft in
there March WL and for our so there’s a right in the left here the right is
gonna go on the clutch side of the engine and the left is gonna go on the
flywheel side so the right is gonna be at the bottom pop this into place here and then the left side is going up top and finally time to put the shift drum
into position so basically they’re just gonna push the shift Forks out of the
way a little bit make room for the drum and it just slides face down into that
bearing make sure you get it seated all the way now to get the shift Forks into
the drum they just pop right into those little grooves there so once again you
might have to pull up on the gear farther down like that to get it to pop
into place and then the shift pen will slide right through those Forks to lock
this whole setup into place you got to make sure that pin goes in all the way
and it’s gonna be the same deal on this side as well it’s got a pull up on the
gear get that pin in and then slide the retaining pin through the fork just like
that pretty simple now that I’ve got everything within the cases together
just gonna spin the gears and make sure they work smoothly with each other Matt
you can already tell a difference with the isotropic finishing the gears just
spin flawlessly and to go through the gears basically how this works is when
you shift the transmission the shift drum spins and therefore moves the forks
on the shafts so I’ll give you a little demonstration here you got to have the
shaft spinning for it to be able to shift as you can see as I’m spinning the
transmission and shift drum simultaneously it’s moving the gears on
the shaft and that’s what’s engaging the different gears on the transmission so
people make it out to seem like rebuilding a transmission or a bottom
end it’s a lot of work and it’s super complicated but in all honesty it really
is not I mean it looks like there’s a lot of gears and a lot of parts here but
once you take your time and you follow a service manual or a video like this it
really isn’t too bad anyone can do it so what we’ve got up
next is installing the dowel pins the center case gasket these are the dowel
pins right here and there’s also an opening that goes up front once we have
all that in place the left case will be ready to go on for
the Dell pens I would definitely recommend putting some anti-seize
lubricant on them they are the most common thing that rust or seized up on
an engine especially the front one up here that one always gets a bunch of
water in there and it rusts and it’s really hard to split the cases at that
point it’s gonna apply a light coat of anti-seize to each dowel pin here and
before I slide this over Inge and the gasket on I’m gonna put a little layer
of grease on the entire gasket surface so what this does is it helps keep the
gasket into place during the assembly and then if anything happens like I need
to pull the crankcase back apart the gasket will not be stuck and it won’t
rip as easily when I split those cases back apart so you just never know when
you’ll have to pull those cases back apart during the assembly process and
the grease I’ll be using is just this general Maxima waterproof grease so it
doesn’t really take much of a layer on there just a light dab around the whole
thing so this piece up here is just to keep the whole gasket together we’ll be
cutting it at a later point but right now I’m just gonna cut it in half so
that way it’s not holding up this part up top here so now I can get that gasket
all the way down onto the case so what I’m doing here is just making sure all
the holes line up kind of tacking it down to grease and one last thing I’ll
do here before I slide the left case on is squirt some assembly lube on to the
transmission gears and some of shifting components to try to get it on every gear set and then
get it inside of each one of these shift drum grooves and then go through the
gears to get that assembly Lube spread around now there’s a few things I need
to do this left case to get it ready to install on the engine it’s gonna squirt
some assembly Lube into the bearings grease up the gasket surface and then
once again I’m gonna heat up the socket so that way I can warm up the inner race
of the bearing and that’ll allow the crank to slide right through now a left
case should just slip right on but I gotta be quick about this before that
bearing cools down okay I kind of lied here the left case
isn’t sliding on like I’d hoped so I’m gonna have to bust out the Tusk
crankshaft puller tool this is gonna thread onto the end the crank and pull
the crank into the left crank case or push the left case down onto the crank
whatever way you want to call it so first we’ve got the adapter for the
puller and then a nut that threads onto the end the crank read this all the way
down and here’s the puller shaft reading onto the crank then we’ve got the polar
body here just slides over the whole thing there we go so ideally you’d like to
have these bars underneath the puller that way you have a nice flat surface to
get leverage on but from the looks of it not gonna have enough thread here so I’m
just gonna have to go directly onto the crank case like that should still work
out just fine this should be pretty self-explanatory
now as I tightened down this nut it’s gonna pull up on the shaft which is
connected to the crank shaft and push down on the crank case at the same time
so it’s gonna bring this whole unit together all right time to get polling
on this crank as I’m tightening those nut I got to make 100% sure that this
thing is going on straight every couple seconds I’m just gonna check the dowel
pins make sure they’re lining up and all the pins and shafts as well looks like everything is lining up so
far just gonna continue crank it on this thing got everything pressed together seems
like everything lined up really well so first time using this tool and I’m
pretty impressed seems like it worked pretty well once again this is a tusk
crankshaft puller tool and they’re available over at Rocky Mountain I’ll
put the link down below to where you can pick one up super handy tool to have
definitely save the day on this build alright the cases are finely pressed
together I’m gonna rearrange the engine here on the stand and then start popping
in all these case bolts now for the case bolts I’m gonna get
them all started into the threads before I start tightening things down sometimes
they’ll get hung up on the gasket and you kind of have to shift things around
to get them to line up so it’s a bit of a guessing game when
you’re putting these bolts in you want about 3/8 to 1/2 inch here before you
start threading the bolt in the case so that one looks about right let’s find
one little lower hole yep that’s the correct one now it’s pretty important to
try to tighten these down evenly so I’ll go up to the top give it a little
tighten come down to a bottom bolt give that a little bit of torque it’s kind of
work my way around in a even pattern here the torque on these case bolts is
only going to be about 6 or 7 foot-pounds so if you have a quality
torque wrench that you can trust go that route or you can just tighten by hand
that’s what I’ll be doing here if you’re gonna be tightening these bolts by hand
try to fall on the side of caution because they do strip out pretty easily
of course you want them tight but try to be really careful with them and while
I’m at it I’m gonna go ahead and install the drain plug with a new crush washer
now that we’ve got everything together and tighten down just gonna go through
and make sure everything spins without any major hesitation crank feels pretty
good transmission as well I’m gonna install the piece on the end of the
shift drum so that way you can go through the gears make sure everything
is functioning properly you definitely don’t want to forget this little pin
that goes on the end of the shift drum it’s gonna go ahead and torque this bolt
to 16 foot-pounds and then I’ll be ready to go through the gears and make sure
they’re all good so just like before as I’m spinning the transmission shafts I
am going to spin the shift drum as well all right I’ve got some bad news guys so
when they had the cases together I noticed there was a little too much
side-to-side play in the counter shaft within the cases and things just didn’t
feel right and it wouldn’t shift in the neutral so I pulled things apart you can
see I’ve got the cases split again and I dug into this counter shaft so
underneath this top gear there’s supposed to be a thrust washer sitting
right here and for whatever reason it wasn’t in there got lost throughout the
process or wasn’t even in there from the first place you know maybe someone tore
into this engine before and never put it in but regardless I’ve got to order a
new one not a big deal you know be it a couple extra days to get this thing
together but those are just the type of things you run into you during an engine
build so it’s not always gonna be sunshine and roses with this stuff
sometimes a little $3.00 washer will hold things up
you just never know it is part of the deal I’m gonna show you guys why that
little thrust washer is so important to sly this gear back on so I’ve got it in
first gear everything seems to be spinning fine and then it’ll come to a
stop right there it starts binding up so if you pull up the gear to simulate that
little washer in there everything spins together just fine there’s no binding at
all so I’m gonna pull this back apart and show you the little gap there where
that washer should be just gonna put the collar and the top washer into place so
you see that little amount of play there where that washer should be that makes a
world the difference in how the transmission spins and chips it’s crazy
here’s the thing to take away from this if you’re putting things together and
you notice something isn’t quite right or there’s any question whatsoever
don’t hesitate to pull things back apart and double check I mean I would hate to
get this thing together and realize it doesn’t shift into neutral and the
transmission is binding up so always double-check your work especially when
it comes to the transmission I mean that would be a nightmare to pull this whole
bike back apart just for a stupid little washer all right guys I’m gonna go order
that little washer and there’s actually a few other things I need to order up as
well and as soon as that stuff comes in the next video will be on putting this
thing back together and getting the whole bottom end in one piece so that
will include the clutch shifting components violins theater and some
other parts and pieces as well so stay tuned for that video so you guys enjoy
this one go smash that like button it really helps me to continue to do these
videos well I’ll see you all in the next one

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