Chrysopelea
Active Member
Just bought my RV12 a few months ago. Been taking lessons, with everything being fine. Roughly 160 hours total time on plane and engine (2013 model SLSA)
My annual came due, and I assisted the mechanic in the engine aspects of the annual (changing plugs, inspection of everything, cowling removal and reinstall.
Immediately after my annual, I noticed on pre-flight inspection that my coolant level was a little low. I marked it, and after my lesson, it was lower than my mark, and I found drippings on the ground after shutdown and wetness on the underside of my cowling.
A friend helped me pull the cowling, and we Thought we found the leak. Sitting in the plane, it would be the left front cylinder, the metal tube that comes out of the bottom of the head, the clamp for the rubber hose was placed way up at the bend on the metal tube, maybe an inch away from the bulge in the metal tube.
The mechanic found the leak, said it was not uncommon, and let me use his tool to place the clamp properly, just behind the bulge, and I also installed a regular hose clamp behind that clamp just for insurance.
Well, after the next lesson, everything seemed fine, but after getting out of the plane, I found a small puddle, and again found the underside of the cowling wet in the same area, so I'm guessing it's the same piece of tubing or clamps.
My guess is it only leaks after shutoff, when the heat soak causes higher pressures and pushes the coolant out. It's not overtaking the radiator cap spring, and the expansion tank is not blowing over, just dropping in level slightly (like a few tablespoons, maybe 1/4 cup).
I plan to replace the hose and clamps before flying again.
Murphy's law I tells ya. Everything was fine until I had the annual done.
I'm going to pull the cowling later today and maybe run the engine, warm it up, and shut it off to see if I can't see the leak in action.
My annual came due, and I assisted the mechanic in the engine aspects of the annual (changing plugs, inspection of everything, cowling removal and reinstall.
Immediately after my annual, I noticed on pre-flight inspection that my coolant level was a little low. I marked it, and after my lesson, it was lower than my mark, and I found drippings on the ground after shutdown and wetness on the underside of my cowling.
A friend helped me pull the cowling, and we Thought we found the leak. Sitting in the plane, it would be the left front cylinder, the metal tube that comes out of the bottom of the head, the clamp for the rubber hose was placed way up at the bend on the metal tube, maybe an inch away from the bulge in the metal tube.
The mechanic found the leak, said it was not uncommon, and let me use his tool to place the clamp properly, just behind the bulge, and I also installed a regular hose clamp behind that clamp just for insurance.
Well, after the next lesson, everything seemed fine, but after getting out of the plane, I found a small puddle, and again found the underside of the cowling wet in the same area, so I'm guessing it's the same piece of tubing or clamps.
My guess is it only leaks after shutoff, when the heat soak causes higher pressures and pushes the coolant out. It's not overtaking the radiator cap spring, and the expansion tank is not blowing over, just dropping in level slightly (like a few tablespoons, maybe 1/4 cup).
I plan to replace the hose and clamps before flying again.
Murphy's law I tells ya. Everything was fine until I had the annual done.
I'm going to pull the cowling later today and maybe run the engine, warm it up, and shut it off to see if I can't see the leak in action.