T E S T IN G T H E S TA R T E R Checking the Connections Are there Bad/Loose connections on any of these Components? B efo re a n y te sts o n th e sta rtin g syste m , m a ke su re th a t th e b a tte ry connections and ca b le s a re in g o o d co n d itio n . T h e y sh o u ld b e cle a n a n d tig h t, w ith no sp a ce betw ee n th e b a tte ry p o st a n d te rm in a l.
Correct
Incorrect
Correct
Make sure inside nuts are tight.
Incorrect
T E S T IN G T H E S TA R T E R Quick Hits - Try These Simple Tests H igh pitched w hine during cranking (before engine fire s) but engine cranks and fires okay.
D istance too great betw een starter pinion and flyw heel.
H igh pitched w hine is occasionally noticed after e ngine fires. Engine cranks and fires okay. T his interm ittent prob lem is often caused by "starter hang in" o r "solenoid weak."
D istance too small betw een starter pinion and flyw heel. F lyw heel runout contributes to the interm ittent nature.
Loud "whoop" after the engine fires but w hile the starter is still engaged. S ounds like a siren if the engine is revved w hile starter is engaged.
M ost probable cause is a defective clutch. A new clutch w ill often correct this problem .
"Rumble ", "growl" or (in severe cases) a "knock" as the starter is coasting dow n to a stop after starting the engine.
M ost probable cause is a bent or unbalanced starter arm ature. A new starter w ill correct this problem .
"Grinding", terrible grinding/grating noise as starter m otor cranks engine.
S tarter drive pinion gear not m eshing w ith flyw heel ring gear. S tarter m ust be rem oved for further inspection of flyw heel and pinion gear.
NOTE: S o m e sta rte r m o to rs re q u ire sh im m in g . A sp e cific d im e n sio n "gap" b e tw e e n th e sta rte r d rive p in io n g e a r a n d th e flyw h e e l rin g g e a r is n e ce ssa ry.
T E S T IN G T H E S TA R T E R Separating the Starter from the Ignition System T h e sta rte r ca n b e e a sily te ste d b y d isa b lin g th e ig n itio n syste m . • If th e sta rte r tu rn s o ve r fin e w ith th e ig n itio n d isa b le d , th e p ro b le m is in th e ig n itio n syste m . C h e ck fo r a d va n ce d ig n itio n tim in g o r sp a rk p lu g w ire s a re n o t in th e p ro p e r o rd e r. Is there a problem with the battery cables or connections? • If th e sta rte r still d o e s n o t tu rn o ve r, ru n a g o o d q u a lity se t o f ju m p e r ca b le s d ire ctly to th e sta rte r. T h e ca b le s sh o u ld b e 4 o r 6 g a u g e , n o lon g e r th a n 1 2 fe e t in le n g th . C o n n e ct th e Red lead to th e BAT terminal o n th e so le n o id . C o n n e ct th e Black lead to th e chassis of the starter. WARNING !!! B e fo re d o in g th is te st, M a ke su re th a t th e ve h icle is in PARK or NEUTRAL w ith th e parking brake ON.
T E S T IN G T H E S TA R T E R Checking the Starter Wires Available Voltage (While cranking)
Cranking Voltage (While cranking)
C he ck th e a va ila b le a n d cra n kin g vo lta g e o f th e sta rte r a s sh o w n a b o ve. T he d iffe re n ce b e tw e e n th e tw o vo lta g e s e q u a ls th e Vo lta g e d ro p . T h e vo ltage d ro p sh o u ld b e le ss th a n o n e vo lt. If th e vo lta g e d ro p is m o re th a n o n e vo lt, sta rt ch e ckin g fo r e xce ssive vo ltage d rop in th e w ire s a n d co n n e ctio n s b e tw e e n th e b a tte ry a n d th e sta rte r. T h e p rob le m co u ld b e in e ith e r o f th e tw o ca b le s.
T E S T IN G T H E S TA R T E R Checking the Current Draw (Amps) • C o n n e ct th e load tester positive (+) lead to th e positive (+) battery lead. • C o n n e ct th e load tester negative (-) lead to th e negative (-) battery lead. • P la ce amp inductive probe a ro u n d e ith e r b a tte ry ca b le . W ith th e e n g in e is a t n o rm a l o p e ra tin g te m p e ra tu re . D isa b le th e ig n ition, cran k th e e n g in e o ve r a n d n o te th e cu rre n t d ra w (d o n o t e xce e d 1 5 se co n d s). C o m p a re th e re su lts to th e g ra p h b e lo w : Approximately 100 to 200 Amps...
Approximately 125 to 250 Amps...
Approximately 150 to 300 Amps...
ADJUSTABLE LOAD TESTER V O LTS
CURRENT DRAW IS AFFECTED BY: AM PS
• • • • •
G auge of the starter w ires A m ount of drag on the engine Type of starter, gear reduction, etc. Tem perature of the m otor oil S ize of the engine
T E S T IN G T H E S TA R T E R Analysis of Voltage and Current Readings Excessive Current Draw:
A m ps Low
V olts H igh
Low
H igh
Mechanical Possibilities: • W ro n g w e ig h t o f o il • H ig h C o m p re ssio n • C a rb o n B u ild u p • C a b le s sh o rte d to g ro u n d • B u rn t o r b in d in g sta rte r • B in d in g E n g in e
Battery Problems: L o w b a tte rie s w ill ca u se th e sta rte r to d ra w e xtra p o w er, sp in slo w e r a n d p o ssib le d e struction o r o ve rh e a ting of the sta rte r.
Any of these problems can cause high current, leading to further damage of the starting system.
A m ps Low
V olts H igh
Low
Low Current Draw: H igh
T his condition is generally caused by poor connections or frayed cables. U sing a cable that is too thin w ill also cause a decrease in current. C heck to see if all the connections are tight and free of corrosion. If a cable is frayed, replace it w ith a new one of the correct gauge.
