9 Sept 2009
Problem: Tensioner pulley became noise. I got
a quote from Toyota Agents and they quoted me R1,400 for a new one.
They said I had to buy the whole unit and cannot get the pulley
Solution: Removed the bearing and replaced the
bearing only which cost me R38.67
This is how to do it:
NOTE: You must use a good quality bearing like SKF, NSK or Timken and it must be a sealed bearing.
Because the pulley does not have a circlip which hold the pulley
the agents do not want to replace the bearing only, they say you
have to replace the whole unit. In the picture above you can see
that the indentations marks hold the bearing in place.
First you have to remove the pulley. Note that there are two bolts.
The one which is in a vertical position is the tensioner bolt and
you have to loosen this one LAST. Do not try to loosen this before
you have loosened the main bolt fist.
At the front of the pulley is a horizontal bold (A in photo below)
which holds the pulley. Loosen this bolt (A) first, just a little
bit. Then adjust the other bolt (B) in order to remove tension from
the pulley. Once the fan belt is not tight anymore you can remove
the front (horizontal) bolt completely and remove the pulley. Both
these bolts take a 14mm spanner. You must turn both bolts anti clockwise
Once remove have a look at the the spacer at the back before you
remove it. If you put it back in the wrong way around the pulley
will not turn.
Now take a small chisel, old screw driver or punch to lightly hit
the indentations back so that you can remove the washer which is
on top of the bearing. I used an old screw driver and old injector
tip. These old injector tips are very hard and sharp and is the
ideal "punch" to use for delicate jobs like this.
Once you removed the indentations you can turn the
pulley around and hit the bearing from the back to remove it. Do
not bother taking the washer out first because it will come out
when you remove the bearing. It is of course better to rather use
a press if you have one.
Once you removed the old bearing you can now put in
the new bearing. The bearing size is NSK 6301.
It has a OD of 37mm, ID 12mm and is 12mm thick with rubber seals.
Putting the bearing back in needs some skill. You
must nether hit the bearing's inside with a hammer. You can only
lightly tap the outside ring if you know how to. You must do this
carefully. You can also put the old bearing on top of the new one
and rather hit the old bearing. See the next two pics.
Hitting it directly on outer edge
Old bearing on top
Once the bearing started to go in you can put it in
the vice to press it in if you have a vice or the best way of course
is to use a press
and press it back in. Note that while pressing it you also put pressure on the old bearing and not the new one in order to prevent damage to the new bearing.
Press with vice
Once completed you have to put back the washer and
then take a centre punch and make new indentations marks. These
indentations do not carry a lot of load. All it have to do is prevent
the bearing from moving outwards.
Replace the front washer and rear spacer.
Now put the pulley back in. Tighten bolt A by hand
only. Then put the fan belt in place and set the tension of the
fan belt with bolt B. Turn it clockwise for more tension and anti-clockwise
to loosen. Once the tension is correct then only tighten Bolt A.
I am not sure what the correct tension for the fan
belt is but the general rule I use is to twist the fan belt When
it reach the point where I cannot twist it more than 90 degrees
then it is OK.
TIP: While you are busy with this you might as well
check your fan belt If it has cracks in rather replace it. You will
note that it is behind the fan. To remove the fan belt just move
it over the fan blades one at a time.
Idea: There was a suggestion that one cut a groove
in the pulley for a circlip. This will make the tensioner pulley
serviceable. Thus you can easily replace the bearing next time.
Because the casing of the pulley is only about 2mm thick I did not
feel at ease to cut a 1mm deep grove in the pulley. So I decided
to rather investigate the matter further before doing it.
If nothing goes wrong this whole operation should
not take you longer than 40 minutes.
Bearing No NSK 6301