Sunday, May 29, 2016

Preparing The Cooling Duct For The Oil Cooler

Now that the oil cooler is enclosed within the oil cooler box, the assembly needs to be mounted onto the cooling duct. The fiberglass cooling duct will eventually be bonded onto the lower cowling and in addition to being the mounting point for the oil cooler assembly, it will also create a tunnel to provide cooling air for the coolant radiator. However, prior to mounting the oil cooler assembly onto the fiberglass cooling duct, the fiberglass needs to be trimmed down to the scribe lines along the outer perimeter of the fiberglass duct and also the rectangular opening the oil cooler will mount onto. Of course, wouldn’t you know I would pick the first 90 degree day with high humidity to sit in the sun and grind, sand and file fiberglass all afternoon. I used the Dremel outfitted with a cutting wheel then sanding drums to get the fiberglass close to the trim scribe lines.
Sitting in the hot sun on a hot humid day using the Dremel outfitted with a sanding drum grinding away fiberglass to get close to the scribe lines in the area where the oil cooler will mount.

Once the Dremel work was completed, the cooling duct was hand sanded using a sanding block and tweaked in a couple of places with a file.
Hand sanding the edge of the fiberglass duct to the scribe lines.

After the sanding was completed, the opening in the duct was placed over the oil cooler and the overall fit was checked.
Overall fit is looking good at this point, just needs a couple of tweaks.

A couple of spots were tweaked a little and then the frame of the cooler box was clamped to the duct so the two nutplate holes on the top flange of the oil cooler box can be match drilled into the fiberglass duct.
The oil cooler assembly clamped to the duct after being centered in the opening and ready to be flipped over for drilling.
With the oil cooler assembly now clamped onto the fiberglass duct, it's in position to match drill the fiberglass duct using the two nutplate holes that can be seen on the top flange of the oil cooler box.

By this time it was getting late, so stopped short of drilling the holes so that will be the next task during the next work session.