10R-8097 ECU repair. Dual ECUs With water Intrusion issues

Wow let me tell you! For a computer that will be exposed to mud and water and the elements, they sure don't seal these computers well at all from the elements. the flat plate design with no real ability to breathe from thermal expansion. No wonder the seal failed and water got into both ecus. CAT paints the aluminum black even on the seal area and that also causes a failure point. Painted surfaces are not made to mate together especially when paint doesn't bond very well to alum surfaces to well for the extremes these are put through. The water intrusion came directly between the paint and aluminum. The thermal expansion over time made the paint release from the aluminum and it made an oxide layer and eventually got into it. The screws on the bottom lower half of the ECU were rusted into the aluminum and were difficult to remove. I was thinking of low temp aluminum brazing but it probably wouldnt bond properly. All the drivers in the left side of the ecu had to be replaced and set into thermal adhesive. The board had several SMD capacitors that needed replaced. I didnt have any wire diagrams or info on these unfortunately so I had to test things across the board and have the customer get the two ECUs and test them out on the tractor. It should get him back in service. 

To be continued possibly..