Cowl blocking tip

I have installed my IO-360M1B on my RV-7A and am working the cowling. Now that I had set the top cowling's height in relation to the prop spinner, I needed to devise a way to block that cowl half so that it stayed at the perfect height. After measuring the gap between the small stainless steel fuel lines running from the engine's top-mounted fuel injection spider, I used 3/4" wood boards that sat on top of the tubes above the cylinders and under the fuel lines. I screwed a block of 2"-by-4" wood onto the forward ends of the boards and butted the boards back against the engine case aft end.



I am using a sheet of 1/4" thick oak veneer (from the Home Depot Aviation Supply Warehouse) acting as a spacer between the prop spinner backplate and cowling forward edge. I had already marked reference lines on the prop spinner backplate to show where the forward center cowl flange edges should align when the cowling is at the proper height. The "proper height" included allowance for future engine sag. I then started the process of:
- removing the cowling
- sand down the two 2x4 blocks a little at a time
- reinstall the blocks atop the engine
- reinstall the cowling and check the alignment and height
- repeat...
- repeat again...
- ...until the cowling sat at the proper height with the forward flange edges aligned with the prop spinner backplate.



I checked again, this time with the 1/4" oak veneer spacer removed from behind the prop spinner backplate. PERFECT alignment, height, and spacing.

Keep Calm and Build On

An easier way is to use two clecos through a short piece of aluminum angle and cleco it to the middle of the top cowl and let it rest on the backplate. Fill the holes later.

Best,