[TowerTalk] Thrust bearing re-grease

[Doug Renwick]

Very interesting mainly because the current 'wisdom' re the TB-3 and
TB-4 thrust bearings is to not grease or oil them ... run them dry.  So
now we have a conundrum. I have run mine dry from the beginning as
advised.  But I am beginning to lean towards lubrication.  But
sparingly.  A light application of a light oil or light grease
(snowmobile) might be the answer.

Doug


-----Original Message-----
 
Subject: Re: [TowerTalk] Thrust bearing re-grease


TT's 
 
Having limited enc with the Yaesu thrust bearing. My thoughts are aimed
at the Rohn TB-3 TB-4 style thrust bearings.
 These Bearing have been on the Armature scene for many a moon and as
Steve has said Have no provision for a grease fitting and maybe under
normal applications  you will get many a year service from them.  Well I
am a belt and suspenders type... I learned how to remove the internal
allen set screw by die grinding the punched  the secured them in place.
The first bearing was removed from a full size 40 meter beam, The beam
was left in the N/E position 95 % of the time. Upon examining the unit
it was obvious while rotating the base and top in opposite it felt LUMPY
! like a old  COLD bias ply tire . This bearing was to be used hopefully
on my new 40 meter tower project. I disassembled the unit .. Lot's fun
shacking the balls out the little hole where the set screw was :)  you
then can separate the two.. WOW the 20 plus years of rocking had in fact
made small shallow incidents from the steel balls. A quick smooth out
with a round noise digrinder grinder smoother it out.. I then got new
balls and used an acid brush to give the race alight coat of blue
snowmobile grease. 
I have done this procedure on  other  installations where the TB3 was
used... 
 
In the first two weeks of this Oct I rehabbed the 40 meter tower.. New
Paint New feed lines , rebuilt rotor and new Beam ( y'all might
remember my adventures with the CC 240MX )  I also disassembled the TB-3
that was installed in 1990 18 years ago and it was Shinny and turned
smooth as glass, there was even a slight residue of the blue grease
missed with dust 
 
Sorry for being long winded but I live by the  KISS  theory and ounce of
prevention is worth two tons of CURE
 
 
 my .02
 
 
 Wayne W3EA