okay taking a look at continued mean bearings
the first thing where they do is identified the type of bearing that's
being used in this engine
and the next thing we're going to do is take a look at it physically how we do
the measurement process and if i noticed it falls within manufacture special
occasions for permissible
and float for and play in the current staff
technically the crane step then
thrust
cause the crankshaft to move back on the hill kal cut years on the crankshaft in
the cam here itself or any accusing gears in the frontier train of the
engine
so we need to do is make sure that we have that particular running clearance
in there
so that we're not
uh... going to cause any staffing scoring corporations
in the end for the crank shaft
it's also important that if we have excessive crank shaft and play
what happens is the every time the clutches pushed or engaged in the
vehicle
that the craig moves ahead
and then walks back under natural movement of the few local cut here's a
mature trees
so that cause thats awsome movement of the test and and the reciprocating
assembly in the solar which causes premature wear
and usually will cause an out of rome condition
so taking a look at engine mean bearings
and i'll call talk about this is a moral that'd detail in just a moment we have
of split shell bearing
that here has thrust flared surfaces on it
these flinches on either side of the craig itself
help control
the and floated the crank shaft
four and a path in the movement as it's moving in the engine while it's
operating
sulfur take a look at these two particular bearings
they're completely different than the one that does not have the side on
normally this is the style of bearing that we've seen
coming out of of connecting rods and also standard means without being
married is but not being thrust
if we take a look at the caterpillar barry
for these various happen to be a usaid
so we could see a couple of different
character differences here one we have whale holes in this one
only one in this one
this is a plane type hearing they're both plane tight friction bearings
but this one actually has an extra area for an increased amount of volume of
lubrication
in the event that the engine oil pump
pressure regulating valve
or pressure relief valve cannot compensate for eight changing engine rpm
or even cavitation from the bottom end from the pickup
of the engine oil pump
so this allows an extra volume oil here so that if we do have an extra load on
it we have sufficient volume of oil a lot of manufacturers have gone to this
style as opposed to a plane style that does not have that extra group
the manufacture this particular very few caterpillar what they've done here as
they have allowed this pairing
to run in different configurations so one in the saddle
and one of the cap
and it's taken the guesswork out up the correct position because we have
multiple holes
which can be used for multiple engine designs
so this prevents the manufacturer from having to actually
create a brand new bearing for various styles of engines
so one other thing that we take a look at on these bearings is attained in in
preview of previous videos
they've indicated that it taneous believe for the purpose of installation
of the bay area it does not all that there
what holds it there is the crush
and what its crest in the position that the cap forked on either the mean cap
for the connecting rod cap
that a wholesome radio pressure all the way around
on both
bearings
to keep it in its respective position his previous videos to show you the
proper procedure for checking
the running clearance which we called the you'll see which is vertical will
clear
we have to have the right about apoyo their to help lifton support that
rotating component
if we have the right amount there it provides lots of longevity to wear from
the middle of the spektr up to the maximum stack
often take a look at
the next thing on the bearing is identifying
it bearing through apart number the
so to bring the dean of bristol life here
i'm just gonna use and shock
and go over top of the numbers and then wipe off the access now we can closely
look at the bearing identifying numbers to determine what bearing we need to put
back into the entrance it so if we take a look at this split childbearing now
with thrust flanges on it so this is our main thrust bearing
and i've used it shock to bring the numbers to light so i can see the actual
manufacturer
part number here
he tells me the position of this pairing which is the op-art therein shall
and it also tells me it's a one twelve as t_v_ and ask t_v_'s stands for on
this very standard
which indicates that it's a standard that mentioned therein
to get the running clearance established by the manufacturing process of the
crank shaft
the bore as well as the bearings
when it's all prince positioned and installed in the engine
okay taking a look at the next day ring that i have your freedom education
they say we don't see the s cd labeling on here
we have a smaller number which indicates he aftermarket or a different
configuration of the application of this particular berry
it's also telling us here and i've used it to bearings for the destruction
purpose that one was an upper
and this was a lower so it takes the gas work
outcome installation procedures of the very
we can always look at it now then if i had some lower
reno's look at it and identify if it's an opera
the important factor rate here is this value
and you can see it it's kinda hard to see but if you sit shock to bring it to
light that we have point zero one zero which is ten th out
so we see the indication of ten thousand tells us that we have a ten foul
undersized barry
so that means that craig journal is smaller than
all we have
and all its plane that
as we continue through the video
continuing on take a look at a different style of a ring again
is we have a split shell bearing the upper and lower two different
applications like a gave previous instruction on but we also have
something here at this minute manufacturer has used to control the and
float
on the other bearings we have a thrust flange on the bay area
and it's part of the split shell
this one is just the split shelved and that we are actually use brash a m
that's lights down into the block
sits in the position
and between two of them
controls the and float so we would have one on one side one on the other
and the manufacturers prescribed based on the size of the mention of the
sheehan's
how much and play it's going to control
kate if you look at
the crank shaft and understanding
uh... the particle of clearance and how the effective of the undersized
crankshaft infects the
bearing that needs to be installed
we'll take a look at it now
sold we have our crankshaft here
and we have are bearing
borer
and we have are bearing which is indicated in blue
so the running clearance
would be right in here
and that's running clearances known as their birth flower are clear
which is going to establish how much it will we can actually get into that area
to help lifted support that component
the daring
began
in this particular case would be indicated as an advanced t_v_ bearing or
standard damascus
berry has a certain amount of burt with their health support the loan
uh... in the running clearance it we need
for this printout
when crankshaft his machine down
we're actually going to go under size
and we go under size we're going
lol the original or yen dimension
of the train
so now if we mission that were actually going to see more worried than
we're creating an
undersized journal
were technicians misunderstand is if the crane becomes warren
we need to put up
bigger buried in there
so critical look at this next item
so if we can go over the last day and all we and specification on the korean
size
so we've actually gone to what's called a u_s_ support undersized mentioned
that means that that crank journal is smaller than
but we have
and with smaller then we need to have a very good that's larger
to help
bring back the running clears
as in the prior diagram we have a running clearance in here indicated in
black
and that's the clearance it we have between the buried
in the journal surface install
that gives us our the falsely again
you can see dimensional leave on this diagram
we have more birth year
the birth takes up material
to bring the bearing phase closer to establish the beatles c
so now what we're doing is we're using in undersized dimension bearing
to support
the larger clearance when the barings install
the problem is is right here
the thickness of this barrier
right in here
is now greater than
hui and
which means we have more material there
now the problem happens during writing operation
is we have more questions
now for that bearing to be squeezed out
and when we do impact loading in the conditions such as arrived bearing
application within undersized bearing
we could potentially squeeze that barry that it's actually known as a condition
where we get buried squeeze where crushes the bearing down from the impact
loading
and eventually creates way too much vertical oil clipped
when that happens
that we don't have their prepara tion clearance
and our internal oil pressure drops
because the boy now becomes bigger
decreasing
the size of the capitol
increasing corporate media creasing the amount of
pressure in volume available to the bear