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Hot spot above Rudder pedals

gharding

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I have a fairly new RV14 (1 yr old - 90 hrs TT) that I purchased a few months ago. First long trip since the purchase and first night flight at altitude where I noticed a hot spot, actually feels like hot air blowing into the cabin above the pilots left rudder pedal. Not being the builder of the aircraft and new to RV’s, I am curious if there are common issues of hot air into the cabin and recommended fixes. I just completed the flight late last night and have not had to a chance to investigate. This along with a fair amount of heat from the area in the cabin along and above the exhaust needs to to be addressed or investigated as well. Any thoughts?
 
The cabin heat flap isn't closing all of the way, those things pump out a lot of heat even with a tiny opening.
 
Though the cabin heat knob is fully closed, I do need to check and make sure the door is in fact fully closed. That may very well be my problem. Has anyone added a heat shield to the area above the exhaust to reduce the heat in the cabin above that area? Thanks for your response.
 
He also has an inverted oil system mounted hot side of the firewall right above the left pedal ... do those things radiate enough heat to where you would feel it through the firewall?
 
Maybe a no touch thermometer next flight to see if it's the firewall itself in that area vs the heat valve. Interesting possibility.
 
The heat was not radiant but more hot air flow, so I think the possibility of it being a partially opened heat valve is most likely the issue. As soon as I get back to the airplane, that will be the first thing I look for. Chris, your suggestion to use an infrared thermometer to further investigate, sounds like a good plan.
 
In general, an infrared thermometer won't work properly when measuring stainless. You can however get an accurate reading if you apply some masking tape to the measurement spot. The tape will be the same temperature as the underlying metal.
 
My guess is that it is from the cabin heat. For installation, the little flap door needs to be shimmed to properly close without any force. To make sure it is positively closed, adjust the cable in such way that it puts a bit of force on the flap door in the close position.

You can always disconnect the scat tubing from the cabin heat box and go for a test flight to see if you still feel the heat in the same way.
 
I am also noticing a far amount of radiate heat from the area above the exhaust. Has anyone applied a heat shield in this area? If so, please share any recommendations. Thanks
 
I have added a layer of Fiberfrax inside the tunnel, bottom side mostly to shield the fuel line and fuel pump , which covers the top of the exhaust and added a layer of heat shield barrier on the sides of the tunnel (outside) and that has helped very much. Fiberfax is the most effective way but it would be hard to attached it to the stainless steal of the tunnel from outside.


https://www.amazon.com/gp/product/B00029KC2K/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1
 
I applied my Fiberfax to the outside of the tunnel and covered it with s.s. foil just like I did on the firewall. I made S.S channels/angles and riveted it in place with S.S rivets. Very pleased with the appearance and it's staying in place well. If I could post photos I would.
 
I applied my Fiberfax to the outside of the tunnel and covered it with s.s. foil just like I did on the firewall. I made S.S channels/angles and riveted it in place with S.S rivets. Very pleased with the appearance and it's staying in place well. If I could post photos I would.

I did the same thing then I applied the high temp 3M caulking to the corners to seal it up. Works great.
 

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My guess is that it is from the cabin heat. For installation, the little flap door needs to be shimmed to properly close without any force. To make sure it is positively closed, adjust the cable in such way that it puts a bit of force on the flap door in the close position.

You can always disconnect the scat tubing from the cabin heat box and go for a test flight to see if you still feel the heat in the same way.


This is very much needed at least on mine. I put a shim between the hinge and firewall and it closes completely with no pressure required.
 
Temperature FWF pilot side

My second battery is located pilot side low and I have a thermocouple that reads the temp. In flight runs 50 to 60 F over ambient and after landing when taxiing runs 70 - 80 F over ambient. It’s a warm location for sure.
 
Firewall cockpit side insulation

I don't want to make a possible problem a probable problem but has anyone looked at this. Dan has done a lot of work on firewall issues and safety but could not find anything that covers this material. The area right above my left rudder pedal gets very hot on the 14. I've placed temp stickers on the FWF side (These seems to work very well) and see max temps in the 160 to 170 F range. Please direct me if possible.

https://www.designengineering.com/stainless-steel-acoustical-floor-tunnel-shield-22-x-19/

Thanks
 
I don't want to make a possible problem a probable problem but has anyone looked at this. Dan has done a lot of work on firewall issues and safety but could not find anything that covers this material. The area right above my left rudder pedal gets very hot on the 14. I've placed temp stickers on the FWF side (These seems to work very well) and see max temps in the 160 to 170 F range. Please direct me if possible.

https://www.designengineering.com/stainless-steel-acoustical-floor-tunnel-shield-22-x-19/

Thanks

As a general rule, you can safely use almost anything on the engine side if the only goal is comfort. However, remember stick-on products are useless for fire protection. They simple fall off when temperature gets high enough.

Seems to be some confusion in the marketing department above. The webpage calls it a stainless steel product, but the linked data sheet says it's aluminum. I don't see that as a problem for a stick-on comfort product. However, "micro-perforated" would be pretty dumb. Look for something you can keep clean, not oil soaked.

Got a few beta kits out there, full insulation packages, firewall and tunnel, with formed SS transitions, etc. Good for new builds, but probably don't want to retrofit.
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Don't want engine side FWF

Sorry, should have added I'm looking for something cold side FWF. I normally spend 2 to 3 hours cleaning the engine side FWF every oil change. (OCD in me) So nothing can go on the hot side. Would like to find something to use on the cold side. Thanks
 
Allow the structure to heat, then try to insulate yourself from the structure? Other risks aside, it's simply not very effective.

Insulating the structure is far better, both for comfort and fire protection.

This is typical summertime cruise configuration, shoes off for max legroom:
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Agreed and thanks

It appears they might have mixed up their product data sheets with the aluminum products they sell. Yes another reason is I am fairly tall and like to stretch out and normally don’t wear shoes to fly. Thanks for the input.
 
Spongy cabin heat control

I had the same issue (on my right side). I finally detected the hot air flow after letting my buddy fly and I took my shoes off and felt the blast of hot air! So I completely dismantled the dual exhaust muff heating system and taped the flapper closed. Solved that problem!

But it created another problem (and it wasn’t the need for heat). The exhaust muffs and the SCAT tubing airflow acts as a heat reducer on that side of the engine. It made my alternator too hot and it ate itself. I also found out the builder forgot to put a tube in for air directed onto the alternator.

I rebuilt half the heat system (going to the left side only) and put back in place all the exhaust muffs. And added an air vent to the alternator. All seems well.
 
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