N9405V Posted January 24, 2015 Report Posted January 24, 2015 I went to check on my 1970 M20E today after about 3 inches of rain yesterday and saw a few drips of water coming off of the bottom. So I crawled under, pulled a couple of inspection panels off and this is what I found. Any ideas where the water would penetrate? There are two side vents that are my leading culprits. A new cover is definitely getting ordered ASAP, but I'd like to stop the leaking first. I soaked up as much water as I could. Any suggestions appreciated!
N9405V Posted January 24, 2015 Author Report Posted January 24, 2015 These are the vents I'm talking about. They are not under my cover. The baggage compartment floor is dry and no musty or wet smell in the cabin.
N601RX Posted January 24, 2015 Report Posted January 24, 2015 Antenna, overhead air vent drain stopped up, windows 1
John Pleisse Posted January 24, 2015 Report Posted January 24, 2015 Might be a good time to check sealant on side windows and windscreen. Check side panel insulation for any moisture. You are in compliance with AD 208 A and B, right? 2
Alan Fox Posted January 24, 2015 Report Posted January 24, 2015 Tough one , Because the tail leans toward the back , it might be coming in the front or the door and migrating back along the floor , also its near the baggage door..
Mark89114 Posted January 24, 2015 Report Posted January 24, 2015 As my roofer says, water runs down hill......
Mooneymite Posted January 24, 2015 Report Posted January 24, 2015 I'd start by checking for a hangar. :-) 1
N9405V Posted January 24, 2015 Author Report Posted January 24, 2015 I'd start by checking for a hangar. :-) I wish................
Marauder Posted January 24, 2015 Report Posted January 24, 2015 I would look for a leak in the drain lines coming from the roof.
N9405V Posted January 24, 2015 Author Report Posted January 24, 2015 I would look for a leak in the drain lines coming from the roof. Is there a diagram showing where these are?
N9405V Posted January 24, 2015 Author Report Posted January 24, 2015 Might be a good time to check sealant on side windows and windscreen. Check side panel insulation for any moisture. You are in compliance with AD 208 A and B, right? Yes
N601RX Posted January 24, 2015 Report Posted January 24, 2015 Is there a diagram showing where these are? On the F model it is an aluminum tube that comes down the pilot side wall of the luggage area and sticks out the bottom of the belly. There is a short length of plastic hose up in the overhead that connects it to the drain on the air scoop.
N9405V Posted January 24, 2015 Author Report Posted January 24, 2015 On the F model it is an aluminum tube that comes down the pilot side wall of the luggage area and sticks out the bottom of the belly. There is a short length of plastic hose up in the overhead that connects it to the drain on the air scoop. Thanks! I'll look for it tomorrow.
Piloto Posted January 24, 2015 Report Posted January 24, 2015 Inside the cabin lift the floor carpet on the center of the back back seat. Check for moisture on the carpet and corrosion on the spar splice. Looks that your two access panels in front of the windshield are leaking. The windshield channels the rain into these panels like Niagara Falls and force water into them. The water propagates through the carpet toward the back. Seal the panels and screws with caulking compound. Also check the door seal for no air leaks. Rung a rag around the door perimeter while in flight for changes in the noise level. Door leaks can cause corrosion on the tubular members. Remove the right side bottom panel below the door to check for structural corrosion. José
Marauder Posted January 24, 2015 Report Posted January 24, 2015 On the F model it is an aluminum tube that comes down the pilot side wall of the luggage area and sticks out the bottom of the belly. There is a short length of plastic hose up in the overhead that connects it to the drain on the air scoop. That is it.
carusoam Posted January 24, 2015 Report Posted January 24, 2015 My C would pass water around the old red rotating beacon. It had no sealant when installed... Best regards, -a-
N9405V Posted January 26, 2015 Author Report Posted January 26, 2015 Ok, drain from overhead vent is intact and there is no wet carpet.... Any other suggestions?
N201MKTurbo Posted January 26, 2015 Report Posted January 26, 2015 If it rains hard the water will run down the sides of the plane and around to the belly. The belly panels are not waterproof water can run right in. The design philosophy is to allow the water to drain out so it doesn't pool in the belly panels. That's why there are drain holes drilled at certain places. If you find that water is pooling in your belly consider additional drain holes.
hoot777 Posted December 11, 2025 Report Posted December 11, 2025 Just pulled my G with one piece belly in for its annual. It had sat outside in a good rain. I was amazed at amount of water in my belly. Will be putting some drain holes in center of the belly. Inside the cabin is like a desert. Any thoughts?
PT20J Posted December 11, 2025 Report Posted December 11, 2025 I’d pull the inside side panels and check the windows for leaks. If they leak, water runs down between the skins and the trim panels into the belly. That’s how the tubular structures rust because the water doesn’t show inside. Pilot’s window is the first thing to check. 1
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