RV-6A Air Intake Falling Apart... Part(s) ?

[Eagleflip]

During the Conditional Inspection, we found an issue. Our RV-6A (2000+ hours!) has developed a problem in the air intake system. It's powered by an O-320 D1A.

My I&A tells me that this part (air intake and "bowl") has simply worn out and fallen apart from vibration, and needs to be replaced. I'm not the builder...and since my maintenance knowledge is akin to a monkey looking at a watch, I'm coming to you for help. What part(s) should I order to get this fixed? BTW, the cowling remains fine.

 

[Jjackh10]

It's called a Filtered Air Box or "FAB". There's a kit FAB-320-1. Or you can buy individual pieces

 

[lr172]

I suspect that the alignment to the cowl opening was less than optimal. I would build a new FAB, add the reinforcements discussed here and take care to get good alingment with cowl opening. Follow the instructions and ditch the worm gear clamp.

 

[fixnflyguy]

If your IA is not familiar with the VANs stuff, make sure he learns all about the FAB and makes sure it is set-up correctly. As others mentioned, you only need the top plate most likely, and if you were to order a whole new FAB "kit", there is a lot more work. That is a common failure to the FAB and snorkel joint being too tight and the transfer of movement from the engine.

 

[Eagleflip]

Thanks for the expertise! Part ordered...input appreciated and relayed to our mechanic.

 

[DanH]

This is typically standard Vans baffle seal, fiberglass reinforced rubber sheet. It get stiff with age, compounding the stress issues. Works better with unreinforced silicone sheet.

 

[lr172]

This is typically standard Vans baffle seal, fiberglass reinforced rubber sheet. It get stiff with age, compounding the stress issues. Works better with unreinforced silicone sheet.

View attachment 101549

Vans got the memo. Built a fab for a guy a couple years ago and noticed vans now supplies silicone in the kit.

 

[Norman CYYJ]

Vans got the memo. Built a fab for a guy a couple years ago and noticed vans now supplies silicone in the kit.

I don't expect the alignment to be out if this air box system has been in use for 2000 plus hours. Replace the broken parts and replace the gasket material.

 

[JonJay]

This didn’t happen over night. This would have shown signs of cracking long before it fell to pieces. As mentioned, the FAB is an area of high vibration and prone to cracking.
Whomever is doing your CI should inspect this area closely at each CI.

While you’re there, double check the seal retention. Double check your mounting plate for cracks as well. Few make it to 2000 hrs unless they were modified.

These are all small tribal knowledge things that many GA mechanics simply have no exposure to. However, inspecting for cracks should be common knowledge.

 

[lr172]

I don't expect the alignment to be out if this air box system has been in use for 2000 plus hours. Replace the broken parts and replace the gasket material.

You could be right. However, my airbox has over 1600 hours on it and other than being dirty looks just like the day i put it on the engine. So these can last a long time.