Coolant System, and EAA Tech Counselor Visit

TLDR

• Installed coolant radiator
• Installed coolant lines
• Received EAA Tech Counselor visit

Details

The main goal today was to install the coolant lines. It ended up being a super long day. By the end I almost lost the energy to drive home.

Anyways, in order to get the coolant hoses installed correctly, I had to finish the camloc installation and the coolant radiator installation so I know the exact location of the radiator to route the hoses.

I also met my EAA tech counselor Jason to inspect my work in the engine compartment.

Coolant Radiator

The coolant radiator are mounted on the lower cowling with two latch locks. It’s not very difficult to install; I just needed to fit the unit precisely before drilling holes for the latch locks. This took me a little thinking to draw a dot on where to drill. The place to drill is pretty close to the side of the cowling so it’s difficult to use a pen. I made a custom tool: took tweezers and bent the tips 90 degrees to face each other. Then I used the tool to clamp on the latch lock’s rivet hole. Then the holes were transferred to the other side of the fiberglass, which was a lot easier to drill.

Coolant Overflow Line

The coolant overflow line was the easiest among all coolant lines to tackle, so I started from it.

It’s a small-diameter line connecting between the coolant reservoir and the overflow cap. The problem is, the nipple under the overflow cap is so close to other parts of the engine, I had no access to use a tool to crimp the ear clamp provided by Sling.

I did send an email to Sling for advice, and they said they actually switched to use locking wire in the factory.

I decided to use something with more consistent clamping power - a constant tension clamp. Fortunately, the tools for a constant tension clamp are much smaller than the ear clamp tool, and with some wiggling I was able to put in the clamp and tighten the hose.

Main Coolant Hose

Routing the main coolant hose was a major pain. I had very little clearance in the back of the engine to do anything, but the majority of the joints were in the back. I had to connect the hose to the coolant ports, make a T-split to get the coolant into the cabin heater, and route it back out to the other side of the coolant radiator. And I also had to manage the hose length by cutting a small chunk at a time.

Heat Sleeve

Part of the hose near the exhaust must be protected by heat sleeve.

I followed what most other people did and bought some 1.5” diameter heat sleeve from Summit Racing. It wraps around the hose and gets secured by velcro. The installation was pretty painless.

EAA Tech Counseling

Jason came by my hangar around 7PM to look over the engine work.

We walked around the engine and I showed him my steps on installing it, wiring (and debugging the fusebox issues). I asked him about wire organization and firewall protection. Jason shared a few tips for my future build. Specifically:

• It’s better to use Tefzel zip ties. (I placed order and will switch them out soon)
• Firewall holes need to be sealed by metal. Just taping over with fire shields is probably not enough.
• Anti-chafing: he pointed out a few places that I needed to work on.