1998 S-10-E Electric Truck EV1 System 110 Inverter/Drive train I found the following modification in the buffer wiring harness for the radiator cooling fan which indicates a failed fan buffer assembly. The assembly's PNs = (on wire = 711) - (on buffer = 27003265 717_) - ( on wire = 712) Unfortunately this is a typical failure and the part is no longer available from GM. Therefore the only option is to de-epoxy the assembly, dianose its failure and repair the original part. The following are a few pictures of this projects progress. More pictures to follow as progress is made. 2009.01 |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
| |
 |
This shows the unit
as found after
purchasing the
vehicle in 2007.
as found after
purchasing the
vehicle in 2007.
Note the lower right
corner of the uni. It
shows and unusual
indentation which is
later found to be the
area of an over temp
failure event.
corner of the uni. It
shows and unusual
indentation which is
later found to be the
area of an over temp
failure event.
Our initial attempt
was to chip away at
the epoxy base but
we quickly learned
that this would not
yield exceptable
results. We later
came across a
progess to slowly
soften the epoxy and
successfully cleared
the board for repair.
This process took
nearly a week of
soaking, removing
material, and
repeaded efforts.
Painful but
eventually worth the
results seen below.
was to chip away at
the epoxy base but
we quickly learned
that this would not
yield exceptable
results. We later
came across a
progess to slowly
soften the epoxy and
successfully cleared
the board for repair.
This process took
nearly a week of
soaking, removing
material, and
repeaded efforts.
Painful but
eventually worth the
results seen below.
Top view. Here is the
basic board at the
final stage of expoxy
removal.
It should be noted
that in this picture
the board is missing
a number of parts
that were removed
for replacement.
basic board at the
final stage of expoxy
removal.
It should be noted
that in this picture
the board is missing
a number of parts
that were removed
for replacement.
Bottom view.
Well, then an
unexpected option
came up. Someone
listed a NOS buffer
on ebay for 0.99
cents. We normally
never give up a
project, but other
projects were calling
and we just had push
the easy button.
We did make some
more modifications,
however, to the new
NOS buffer when it
arrived. As noted in
the pictures to the
right, we added a
good sized aluminum
heat sink &
ceramique to the
original set-up in
hopes of saving it
from the previous
part's fate.
The following are
some different shots
of the new set-up.
unexpected option
came up. Someone
listed a NOS buffer
on ebay for 0.99
cents. We normally
never give up a
project, but other
projects were calling
and we just had push
the easy button.
We did make some
more modifications,
however, to the new
NOS buffer when it
arrived. As noted in
the pictures to the
right, we added a
good sized aluminum
heat sink &
ceramique to the
original set-up in
hopes of saving it
from the previous
part's fate.
The following are
some different shots
of the new set-up.
Resistor scales and
values are hand
written in on this
document.
values are hand
written in on this
document.