PS Magazine - TB 43-PS-514
PS, The Preventative Maintenance Monthly
ISSUE 514
SEPTEMBER 1995
M113A FOV .
.±
9ewar oSAd sE±ing$
W
hen a driver reports a
tHrown outeR fan belt on His
M113A2 caRrieR, some mechan-
ics automaTIcaL±y wrITe it off To
a sTretcHed beLT.
²Hey Remove tHe old be³ts,
iNsTaLL a new seT´ adjusT tHe belT
TensIon to THe proper operatIng
range and seNd The drIveR Hapµ
piLy on H¶s way·
²hen They scraTcH THeir heads
in pUzz³emenT wHeN THe driveR
retUrns a day or Two LateR wiTh
tHe same problem¸
²haT's exacTly whaT will hap¹
pen IF Thereºs a bad oUter bear-
Ing IN the fan drIve id³er pu³³ey»
²He pUlley Has Two bearings ¼
one oN The iNsIde and oNe on
the ouTside. ²hough boTH bear-
Ings´ ½S½ 3¾10¿00À436À7329´
are the same´ The outeR beaRiNg
teNds to faÁ³ more ofTen THan
THe iNner oneÂ
WHeN ThaT HÃppens´ THe fÃN
drive idleR pUlley TilTs sligHtLy
and THrows oÄ TÅe ouTer beLTÆ
ÇTÈs tough To catcH becaUse
The Bad bearIng doesN't squea³É
The inner beaRiNg keeps THe Idler
pul³ey turniNg aNd THe TILT is
so s³igHT THaT iT's Near³y Impos-
sIble To see»
Save yoURseLf some fRUsTra-
Tion Ê noT to meNtion tHe cost of
a New set of Ën belTsÌ by KNowµ
Ing exactLy whaT To looÍ Îor tHe
firsT TIme a belT pops loose:
PS 514
²³
Ïook aT tHe faN id³er pulley arm adJUsTing
rodÐ MaKe suRe tHe TensIon is witH¶n opeRaTIng
raNgeÐ Ñf ItÒs noT´ make iT RigHt» OtheRwIse´ go
To sTep 2¸
2´
Eyeball tHe
RemainiNg two ÎÃN
beLtsÓ Ñf theyºve
sHIFted Toward THe
ouTside oF tHe IdleR pUL³ey´
tHe problem is a bad bearIng Go aHead and
replace boTh bearIngs at The same TIme¸
Back to TopBack to Top
