![\"Burned](\"https:\/\/foxbatpilot.files.wordpress.com\/2014\/06\/burned-coolant-hose.jpg\")
<\/a>Burned coolant hose<\/p><\/div>\n
About 15 minutes into my planned 20 minute flight, I thought I could smell coolant – that peculiar metallic hot water and anti-freeze smell. The cylinder head and coolant temperatures were steady, as was the oil temperature. But the smell wasn’t going away, even if\u00a0it wasn’t getting any worse. Luckily my destination was soon\u00a0within gliding distance, so I throttled back, made a radio call and landed without completing the usual circuit.<\/p>\n
It turned out the\u00a0engineer had moved one of the coolant radiator hoses during maintenance. When the cowlings were replaced, the hose had made a slight contact with the nearby exhaust, enough to burn a tiny hole, through which coolant was dripping onto the exhaust. I should have picked up this proximity during my pre-flight but didn’t. In fact with the top cowling off, the hose was a millimetre or two clear of the exhaust underneath it. But replacing the cowling, to which the coolant radiator was fixed, was\u00a0enough to move the hose\u00a0slightly and enable\u00a0contact with the exhaust. The manufacturer\u00a0subsequently issued a service bulletin requiring a specific clearance between coolant hose and exhaust. They have now re-designed the installation to avoid the problem.<\/p>\n
Next – exhaust. Many years ago, I was flying another Rotax-powered aircraft, fitted with flexible exhaust tubes connecting\u00a0the manifolds to the muffler. In flight, I thought I could smell exhaust fumes. Being an unfamiliar aircraft, I wasn’t sure if this was a trait of the aircraft or a real problem<\/p>\n
<\/a>Burned oil filter<\/p><\/div>\n
However,\u00a0I opened the air vents in the doors and decided to make an unplanned\u00a0landing a few minutes later at the nearest airstrip. Sure enough, one of the exhaust tubes had slightly fractured. Most\u00a0worrying – the hole pointed the escaping exhaust gases directly at the oil filter canister and it was only a matter of time before it would have burned through. If oil had escaped onto the exhaust in these circumstances, I really don’t want to think about the possible outcomes.<\/p>\n
So get to know your aircraft’s typical smells and whether it’s the unusual smell of exhaust, fuel, coolant, oil or brake linings – listen to your nose and take immediate action!<\/p>\n
Anyone else had a similar experience?<\/p>\n","protected":false},"excerpt":{"rendered":"
I was just taking off the other day when I caught an\u00a0unmistakable whiff of fuel. In the event, the smell disappeared quickly and turned out to be the dregs in\u00a0my fuel tester cup, which I hadn’t properly\u00a0emptied. I keep the … Continue reading