M20C Baffling

[robert7467]

Has anyone modified their baffling to remove the aluminum on top of the engine like the newer planes?

[orionflt]

Actually I repaired mine and made it tighter to improve cooling. even though it is a pain to remove the dog house helps direct the cooling air through the engine.

 

Brian

[Jerry 5TJ]

Also not what you asked ... I was able to buy some of those sheet metal "doghouse" parts and fabricate a few more. That plus a new cowl lip seal and some leak patches and it works well.
Yes it is a pain to remove.

[BigTex]

Actually I repaired mine and made it tighter to improve cooling. even though it is a pain to remove the dog house helps direct the cooling air through the engine.

 

Brian

 

Brian, Were you able to measure the cooling improvement?

[cliffy]

Being as how it will affect the cooling of the engine it will be considered a major alteration. It will at the very least require some kind of approved data to do the change or a full fly off to show compatible cooling efficiency with a field approval. There may be some kind of STC available for the swap if you dig. If you can find someone who has done it a received a field approval you can copy it exactly and apply for your own FA BUT it will depend on who and what FAA office you work with.

My dog house cools fine after a little clean up work.

Why do you want to change it out?

[orionflt]

Brian, Were you able to measure the cooling improvement?

yes and no, before i redid my cowling the stock gauge indicated around 375 in cruise, probably close to 500 in climb. now i have an engine monitor so my numbers are more exact. with the baffle fixed and the gaps sealed i see 400 in the climb and 300 in cruise. with some of the extreme cold this winter my CHT's have been below 250 and that is after i removed sealant from the gap on the back of #3 cylinder.

Brian

[jetdriven]

Being as how it will affect the cooling of the engine it will be considered a major alteration. It will at the very least require some kind of approved data to do the change or a full fly off to show compatible cooling efficiency with a field approval. There may be some kind of STC available for the swap if you dig. If you can find someone who has done it a received a field approval you can copy it exactly and apply for your own FA BUT it will depend on who and what FAA office you work with.

My dog house cools fine after a little clean up work.

Why do you want to change it out?

 

I think if the pressure cowling style baffling is in the parts catalog then you could swap to that, no? 

 

I have installed quite a few 1978+ parts on my plane based on that. 1978 baggage door, updated overlapping nose gear doors, LH bump cowl flap, swing gate style cabin heater valve, dual brakes, cleveland master cylinders,  in fact, the -A3B6 engine we got was in the parts catalog.

[HRM]

If memory serves, Airforms sells a kit that removes the doghouse.

 

Frankly, like the others, I don't see the issue. Once you pull the two upper panels everything is accessible--it may be different on my E than what you have on a C.

[ryoder]

Sometimes my M20C baffles me...

[cliffy]

jetdriven- interesting thought

As to parts manual listing I've never really changed anything just because it was in the parts manual as most parts have a specific aircraft serial number range for applicability. If the s/n applicability doesn't match the actual a/c s/n I would think the Feds would take issue. Have you ever had a Feds wave his magic wand and directly approve any of your parts manual changes? Not saying it can't be done (I have to check some more) just asking.

High CHT-

I've never seen 400 CHT on my C let alone 500. My doghouse works fine. 500 in my book is WAY too high. When was the CHT gauge last calibrated? That might make a big difference as would all the connections to the CHT temp lead. The temp probe and lead would also be checked on a calibration bench check, not just the gauge

[Oscar Avalle]

If memory serves, Airforms sells a kit that removes the doghouse.

 

Frankly, like the others, I don't see the issue. Once you pull the two upper panels everything is accessible--it may be different on my E than what you have on a C.

I just called Airforms and they don't have a STC for our mooney...

[Jim Peace]

I may want to redo the baffling around my engine with new.  Any updates on who has a kit for this.  

What is driving this is a higher temp on #3 like we mostly get...

Does anyone have an engine monitor that sees somewhat equal temps on all 4?

Anyone know of an expert on this in the central florida area?

Jim

[Gee Bee Aeroproducts]

Complete to replace felt

Silicone seal

backup strips

silicone foam

silicone cement