Would like to overhaul or replace my Carburetor air box assembly

[M20 Ogler]

The box has some cracking that maybe can be welded. I think I should definitely replace my valve assembly and plate bearing that rivet onto the sides of the box. I’ve not gotten a response from lasar. I sent an email to Mooney earlier today. 
 

what have others here done when dealing with this part? 

[Skates97]

I was able to find a used one, it was expensive, but less than what the shop wanted to overhaul/rebuild it.

[Hank]

My IA repaired mine when one of the hinges broke off. It's now ugly but serviceable instead of being stuck in the power-robbing wide open position.

[apriav]

Aircraft spruce and McFarlanes have bushings and shafts for repairs.

Might be for Cessna or other, but bushings and shafts are bushings and shafts.

A weld or rivets, some repairs and your good.

 

[M20 Ogler]

I think this part from Lasar might work if I’m reading the page correctly. I’m confused why it has a 20 where it says “compatible M20c SN 20-0001 and up” my serial is a 4 digit number.

also the carb heat mechanism looks much different 

Edited July 23, 2021 by M20 Ogler

[M20 Ogler]

Ordered the rebuild kit through Lasar. It’s not cheap. Aircraft Parts Store has two carb air boxes “as removed” I asked for pictures. My current box has a hairline crack. Maybe a good welder can help. 

[spectre6573]

  On 7/23/2021 at 4:33 AM, M20 Ogler said:

I think this part from Lasar might work if I’m reading the page correctly. I’m confused why it has a 20 where it says “compatible M20c SN 20-0001 and up” my serial is a 4 digit number.

also the carb heat mechanism looks much different 

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That one is for the later mooneys 1970’s. The carb heat it not the same and won’t work with your airplane. 

[M20 Ogler]

Thanks. The guys at Lasar said it could work but would be a huge PITA. 
 

I think I can make my original one work if the welder can fix the 2 cracks and Then we’ll use the rebuild kit 600063-900 

[carusoam]

You are right on target Ogler!

That crack needs some stopping…

That wear needs some fixing…

Proper OH parts can really help…

Some more modern installs also had a piece of scat to better exhaust the warm air getting dumped from the heat muff… when not sent to the carb…

PP thoughts only, not a mechanic…

Best regards,

-a-

[DXB]

  On 7/24/2021 at 8:02 PM, spectre6573 said:

That one is for the later mooneys 1970’s. The carb heat it not the same and won’t work with your airplane. 

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Yes - '68 and later to be more precise - that was the year they did away with the troublesome butterfly valve for the carb heat bypass operated by the same cable as the main flapper valve.  I have the 2nd serial number for '68 and that butterfly valve-containing port is merely welded shut rather than missing as in this one (probably because they had stock of older-style airboxes to deplete at the factory).

[N201MKTurbo]

I noticed that Spruce sells new C150 air boxes for $150. I could easily design an adapter to adapt the Cessna box to the inlet duct. Maybe I should pursue an STC just for the fun of it.

[mike20papa]

I appreciate your frustration with the stock airbox.  They are not easily welded as the old aluminum is typically loaded with intergranular corrosion.  It will challenge even the best TIG welder.  Even when repaired, the linkage for the carb heat is lacking.  I cut out the entire upper half of mine and welded in new materials.  This also allows for a recess in the upper portion of the airbox to receive the shutter door and get it clear of the carb airflow under typical op.s.   Not sure what the additional MP is, but at least I know it's optimal.

I have some "left overs" from my rebuild, If you need some help.  

First, get rid of those old "intake ingestible" (junk) needle bearings on the carb heat shaft.  Go MacFarlane elastomeric. 

 

 

Edited July 25, 2021 by mike20papa