Resurrecting a Dead Glow Plug Igniter-2013/04

This battery is crimped together.
This mount  ts around the
battery’s groove.
Glow plug igniters
can range from easy
to repair to not
repairable. The diffi culty in
removing the battery can
be as simple as opening the
igniter and slipping out the
old battery, or as complicated
as going through several steps
only to realize that the only
option is to replace it.
A selection of glow plug
igniters is pictured in the
opening photo. They are
pictured left to right, from
easiest to repair to irreparable.
The fi rst one has a
machined aluminum case,
and to repair it you simply
unscrew the case halves and
drop out the old battery,
insert the new battery,
and screw the case halves
back together. The repair is
complete and the battery is
ready to be charged. When I
opened this one, I discovered
that its battery had been
previously replaced.
The second igniter is also
repairable. I recharged the
igniter and used it to start my
new O.S. FS91 engine. The
next day, it would not heat
the glow plug. I recharged it
and it was again dead after
setting overnight. This time I
noticed that the charger and
the igniter were hot when the
charging was complete.
It was time to replace the
battery, but how? Look at
the one you have and try
to fi gure out how it comes
apart. I disassembled the
igniter slowly, remembering
how it fi t together.
The third igniter can also
be repaired, but the center
wire from the glow plug
connector must be soldered
to the fl at top of the battery
using stainless steel fl ux.
Neutralize the fl ux with
baking soda and water after
soldering.
Use a large soldering iron
and keep the time that heat
is applied to the battery brief
(5 to 6 seconds). This igniter
has a set screw in the side of
the mount that retains the
outer sleeve of the connector.
I had one come loose and the
igniter fell apart in my hand
at a contest!
The fourth igniter is
irreparable; the glow plug
connector’s sleeve is glued
to the negative end of the
battery with conductive
epoxy.
Following are the steps to
replace a battery, which can
Resurrecting
a Dead Glow
Plug Igniter
A step-by-step guide
to replacing the battery
by Clancy Arnold
be used for igniters similar to
the second one.
1. Remove the heavy, clear
shrink sleeve from the battery
and mount.
2. Scrape the label off the
battery and try to see how it
was assembled. If the answer
is an interference press fi t
backed up by the shrink
sleeve, skip this step.
3. Hold the battery in
a vice with the glow-plug
When the author opened this igniter he noticed that
its battery had been previously replaced.
This igniter is tricky to reassemble a er repairs have been made.
Repairing this igniter requires a soldering iron.
A set screw retains the outer sleeve.
The battery in this igniter is glued to the
sleeve, making it irreparable.
connector pointed down. Tap down
on the edge of the mount using a
screwdriver and a small hammer. Work
around the mount until it comes off of
the battery. Do not lose the insulator.
4. Examine and measure the battery.
What size is it? What is different or
unique about it? The battery I removed
and measured is a Sub-C size with a fl at
top.
eBay is an excellent source for batterystyle
information. Do a search for the
different sizes and then scroll down
and look at the technical specifi cations
provided by the sellers.
5. Order a new battery and some
clear shrink sleeve material large
enough to loosely fi t over the mount.
I purchased two NiMH fl at-top 3300
mAh Sub-C batteries for $5.34 and
100 cm of 30 mm clear shrink sleeve
material for $3.68 through eBay from
Recyclepowers, which offered free
shipping.
I ordered two batteries in case I
damaged the fi rst one. The shortest
length of shrink sleeve available that
would work is 100 cm (1 meter). You
will need about 21/2 inches per igniter.
6. Prepare the new battery by
carefully cutting the covering back to
the edge of the groove that is farthest
from the positive terminal, where the
battery is crimped together. Cut the
label, not the metal! Save the insulator
disk to reuse if it comes loose. I used
both insulator disks when I reassembled
the igniter.
7. Eliminate any burrs on the mount
that occurred when removing the
original battery.
8. Ensure that you have all the parts
in the proper locations. Press the battery
into the mount by hand as much as
you can. It will slide in easier if cocked
slightly, similar to mounting a car tire on
a rim.
Mine has a .005-inch interference fi t
and there is a ridge around the inside of
the mount that ends up in the groove
around the battery. I considered heating
the mount and cooling the battery
before assembling the parts, but I got it
assembled without using that technique.
9. Press the battery into the mount
using minimum pressure. I used large
slip-joint pliers to reach across the 2
inches. After it starts moving, work
around the mount to seat the battery.
10. Check the voltage at the glow plug
connector. It should be roughly 1.2 volts.
Record the voltage, wait approximately
24 hours, then measure it again.
11. If the voltage readings are nearly
the same, then it should be safe to
charge the new battery. After the battery
is charged, try it on a glow plug.
In my unit, I nearly doubled the
BATTERY DIMENSIONS
IDENTIFIER LENGTH DIAMETER
AAA 4.4 cm 1.0 cm
AA 5.0 cm 1.4 cm
Sub-C 4.3 cm 2.2 cm
C 5.0 cm 2.62 cm
D 5.0 cm 3.1 cm
Photos by the author
Check the voltage when
repairs are complete.
Pliers are used to insert the
battery into the mount.
The battery replacement  xed
this glow plug igniter.
This shows a disassembled igniter.
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power-storage capacity from 1900 mAh
to 3300 mAh with only a 7-gram weight
increase. This will increase the recharge
time from 10 hours to 17 hours. A
different charger to provide the extra
power could be used to charge the new
battery quicker. The difference
between 1900 mAh and 3300
mAh capacity is the ability to
heat a typical glow plug that
draws 3 amps for 66 minutes,
compared to 38 minutes.
12. If you have another
igniter or other fi eld equipment,
consider labeling them with your name
and address and covering the label with
the clear shrink sleeve material. This is
a good use for all of those “free” address
labels that keep arriving in the mail.
Although some may choose to
purchase a new glow plug igniter, others
may opt to fi x a dead one. Either way,
proper charging and maintenance of
your glow plug igniter will ensure that it
is ready when you are.
—Clancy Arnold
[email protected]
SOURCES:
Recyclepowers on eBay
www.ebay.com/sch/recyclepowers/m.html