I have a client that just purchased subject aircraft. We reside in Pensacola, Florida. While flying we noticed hot air coming from the vents when they were open. Even closed there is warm-hot air entering the cabin. We removed the cowling and found the vents to the cabin blocked off and the heater hose disconnected. This doesn't make any sense to me. Do you have an idea of what may be the issue??

Lamar

The big muffler back of the engine transmits a lot of heat into the firewall and through. The only real solution is the dual exhaust STC from APP.

Reconnect the vents to the scoops in the lower cowling for some airflow. Check the muffler and heater shield for leaks. Look for leaks in the firewall. As Kristen says, the muffler does transfer a lot of heat to the firewall and interior.

Makes sense - Thanks for the input!

Check the rubber steering rod boots too. Especially the left one gets a lot of heat from the single exhaust stack. It eventually becomes brittle and breaks.
An approved fix for that is to install the new boot on inside the cabin side of firewall.

Best, Don

I've had success using a l heat and sound shield product on the engine side of the firewall. Got it from Airtex. Liked it so much I soundproofed the cockpit with it during a re upholstery effort.

I had hot air entering the sidewall vents on climb out. Almost turned around and landed once thinking something was wrong. I installed a small strip of baffle seal on the fwd edge of the fire wall to seal the fire wall to cowl area fwd of the sidewall vent doors. Seams to have done the trick for that issue but it's still pretty warm in the cockpit flying low on warm days. I have wondered too if routing the air from the muffler shroud over board some how would make a difference. All that heat is dumped right at the fire wall.
Matt
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