>To: jtolbert@tricon.net
>From: bristol@coastnet.com (JIM WALTERS)
>Subject: Starter test(long)
>Cc: british-cars@autox.team.net
>Bcc:
>X-Attachments:
>
>John: Sorry that I didn't have time to reply to your request for help
sooner, I probably could have saved you a lot of time and trouble, let alone
money. In regards to your "click" symptom: In the case of alleged battery
problems, always try the easiest test to diagnose the problem first. 1: No
click when key turned, turn on headlights; no lights, wiggle battery
terminals; still no lights or click: likely dead battery. 2: Click heard
when key turned, turn on lights; if lights on bright turn key again: audible
click and lights go out, problem is likely loose or coroded battery
terminals. (Slight possibility that it could be a loose connection on the
solenoid, this is where the main power feed for the wiring harness connects
to battery power, however rarely happens compared to battery terminal
connection problems.) 3: Click heard when key turned, turn on lights; if
lights on bright turn key again: audible click and no change in lights,
problem is solenoid or starter. To isolate problem to one or the other, the
test is slightly different for the two types of Lucas starters, pre-engaged
or inertia drive; yet applies to all cars. The inertia type of starter as
used in the Spitfire, Mini, Sprites, Midgets and pre-68 MGB's is identified
by the remote mounted solenoid, that is, the solenoid is mounted on the
firewall or inner fender of the car and is attached to the starter by a
length of cable. To test this type of starter perform the steps in #3 with a
12 volt test lamp attached to the cable terminal on the starter itself, if
the solenoid clicks but the test lamp fails to light, the solenoid is
faulty, if the test lamp lights up when the solenoid clicks but the starter
doesn't function then the starter is faulty and will have to be removed for
repair. When removing this type of starter be very carefull not to let the
post turn when undoing the nut which fastens the cable to the starter, if it
is allowed to turn even a small amount it can break off the connection to
the field coils inside VERY easily, meaning that you will not be able to
repair it and will have to purchase a rebuilt unit. A lot of the field coils
in these starters are aluminum and only repairable by specialized electrical
rebuilders, even the older style that are made of copper require a lot more
heat than the average soldering gun to re-attach them. Back to testing
pre-engaged starters found on post 67 MGB's, TR6's, TR7's and Jaguars. These
solenoids are mounted right on the starter itself and are a cylindical shape
with two large terminals on the outboard end. Same procedure as in step #3
but this time the test lamp must be attached to the terminal on the solenoid
from which a single copper strap or 5/16 inch diameter cable runs into the
inside of the starter, this terminal is the one closer to the body of the
starter right beside the one with all the wires attached. Same results as
inertia starter, same conclusions.(Except that the cable attachment is not
as fragile). This whole test procedure shouldn't take even a novice more
than a couple of minutes, except for difficulty in reaching some of the
pre-engaged terminals. BTW, there is one other scenario that is a
possibility from your decription of trouble. A separate ground strap from
the engine to the vehicle frame to complete the circuit to the starter is
required even though it will sometimes ground through other components. (ie:
Melted heater control valve or accelerator cables on MGB's!). Make sure
yours is intact, on the Spitfire it should be a braided uninsulated cable
attached to the front bottom corner of the engine and the frame nearby or
one attached to one of the bellhousing bolts and the body nearby. Quick
test: use battery jumper cables to connect a part of the engine such as a
head nut and bolt to the earth terminal of the battery. This test is also
usefull with a working starter, if the starter turns the engine over faster
with the jumper connected then you need a better ground strap on it. I know
I haven't mentioned anything about LOW batteries and how to determine
between bad starter/bad battery but this is too long already so I'll wait
until someone has that specific problem. Hope this helps you out or saves
someone else on the list a lot of time in diagnosing
starter/solenoid/battery problems. Oh yeah,one other thing, you don't need
someone else to turn the key for you when testing the solenoid or starter,
just attach the alligator clip of the test light to the terminal to be
tested and ground the bulb end on the dash or steering column somewhere
while you turn the key yourself, works either way around. Jim.
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