[Gmecm] Putting the computer in the engine compartment?

[David Allen]

> Hi there!
>
> The problem isn't heat -- it's water.  Water will want to travel along
> every seam, opening, and will migrate along the wiring harness.  Sealing
> the ECM from water is the chore.

  Yes, I learned that the hard way.  My first attempt at a boat ECM box had
the wires going under a notch in the lid.  It filled with water and wrecked
the ECM.  Then I built this setup.
  It was easy to install the Deutsch connectors.  Just clip the ECM harness
one wire at a time and insert each wire in the respective connector one at a
time. The holes in the connectors are labelled on each side.  Once again, if
anyony wants info I have part numbers and info on obtaining these connectors
from AGCO/ Caterpillar dealers.  I don't sell connectors and I don't have
prices; but I do have part numbers with pictures for 12, 23, and 40-pin
watertight bulkhead connectors, terminals, wire seals, and locks.
  On my boat, one of the harnesses is battery and ground, ignition switched
power, fuel pumps, ALDL, and other things that are not on top of the engine.
  The other connector is the temp sensor,  MAP sensor, HEI ignition timing,
and all throttle-body components.
  There were enough unused pins in the 2 connectors that I was able to
design it so if the 2 are switched, the battery power feed will not be
connected to anything if the battery/ ground harness is accidentally
connected to the TBI harness plug.
  Another good box option is a military metal ammo box.  Those things are
thin-gauge steel, completely watertight and easy to open.  You could have
the ECM and relays in one of those and install watertight connectors through
the box.  It would look better underhood than a Carlon plastic box and
probably be more durable. I used a plastic box on the boat to avoid exterior
rusting. You know- since it is guranteed to be sitting in water from time to
time!
David




>
> David's box is a good example of what to do -- notice the wiring is
> through weatherproof connectors. That is the key -- it's easy to get the
> ECM in a waterproof box, but sealing the wiring's another issue.
> Installing weatherproof connectors in the box, and running wiring from
> the connectors to the ECM is the right answer.
>
> Jay Vessels
> 1982 Chevrolet S-10 Sport, 2.8V6 TBI
> 1984 Chevrolet S-10 Blazer Sport, 2.8V6 (TBI pending)