Gary---Replacing the throwout bearing with another used one is sort of a
crap shoot. It's true that some of the older OEM bearings were good, and
lasted from one clutch replacement to the next. How well the one bolted
up to your spare engine is I can't say from here. One of the simpler
tests is to hand-spin it and listen. A better test is to put a load of a
couple hundred pounds on it and run it for several minutes, and use a
stethoscope.
A new clutch linings are generally .062 thick, when measured from
surface down to the rivets. If your bellhousing is out, I'd replace the
disc if the lining is less than .040 on either side.
The amount of force necessary to depress the clutch (enough to disengage
the disc) is about 250 lb. It varies with the clutch brand. I rarely
change the cover because of spring fatigue. If the grooves caused by the
throwout bearing are not too deep, this surface can be restored (if you
want to go to the trouble), with a 3" sanding disc chucked up in a drill
press.
The resistance for the clutch to engage should disappear when you
reassemble it. On units that start to "stick" its usually because the
assembly grease on the front cover has disappeared. Or the cover and
carrier has worn enough to allow the carrier to cock on the cover. Some
of the new carriers are of bronze, and resist this sticking. (Use the
grease, anyway!)
Dick
From:
ghamilton99@comcast.net
Hello:
I have my interior out on my TR250 & am thinking abut pulling the tranny
to replace my squelling throw out bearing. The clutch seems to operate
normally, no slipping, etc, but I do have a slight resistance on the
return of the pedal about half way up the travel.
I am going to check the clutch fork & other hardware as recommended, but
here is my question.
With all the misery I have been hearing with replacement clutch set ups
do I just replace the TO bearing with a good OE used one I got with a
drive train setup? The backup unit I have was fully assembled on on the
flywheel of a supposedly rebuilt engine. I haven't looked at it in a
while, so I don't remember the brand.
Is there a way to test the spring pressure on the cover & measure the
thickness of the plate & compare to new? When I get the tranny out I am
wondering if I can do a visual & some sort of mechanical inspection of
my backup unit & just replace it as a unit.
I will obviously do the pilot bushing while I have it apart.
--
Gary J. Hamilton
p.s. last time I did a TR clutch was on my 1st TR250 back in '77; didn't
seem to be all the issues of today as parts were all OEM back then.
Thanks for any input.
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