RV-12 Exhaust Decision

[Flyguy16]

I have had the unfortunate circumstance of noticing extra engine noise toward the end of my last flight. Upon post-flight inspection, I found the exhaust loose. When I took off the cowl, I found 3 of the 8 exhaust springs had failed and were gone, leaving my muffler and down pipes severely damaged from excessive vibration. The replacement exhaust (ex-00044) is currently $3150 on vans and that's a significant hit to the budget. I found replacement ball joints and parts on leading edge airfoils, and am considering having a local welder (who I trust with stainless) cut out the old and weld in the new. Parts are $400, not sure about labor costs yet, but likely at least $500 with all the careful alignment required. (Not to mention I don't know when he can get to it)

1. Has anyone done the weld game with this exhaust? If so, any tips/tricks?
2. I've read some about the ex-00044 "upgrade". For those that have it... worth $3k?

Looking forward to any wise counsel as I'm new to the game. Thanks!

 

[bobg56]

after you get it fixed and installed I recommend you run safety wire through the springs as a back up incase of spring breakage. .040 wire would be better than .032 plus adding the red RTV to reduce the effects of vibration. I do a carb sync each year and have had no issues with broken springs, I have 550 hours on my 2010 model.

 

[DHeal]

I still have all of my original (10+ years / 1,400+ hours) exhaust parts / springs on my 2014 RV-12 ULS -- clean living I suppose? However, if I ever have any significant decision to make regarding replacement of this existing system I would likely replace it with Van's upgraded exhaust system that moves the muffler aft and further away from the oil cooler. The improved oil cooling effect of this muffler relocation would likely be a useful operational benefit.

 

[Flyguy16]

Thanks for the tips on the safety wire and rtv. I've had a couple guys at my home field say that to me over the last couple days too.

 

[Flyguy16]

I still have all of my original (10+ years / 1,400+ hours) exhaust parts / springs on my 2014 RV-12 ULS -- clean living I suppose? However, if I ever have any significant decision to make regarding replacement of this existing system I would likely replace it with Van's upgraded exhaust system that moves the muffler aft and further away from the oil cooler. The improved oil cooling effect of this muffler relocation would likely be a useful operational benefit.

Yea, I've noticed in the summer I've been pushing oil temps pretty hard. Seems like from my reading there's mixed reviews on the actual effectiveness of the geometry change. With all 4 muffler and down pipe connections ruined, perhaps I ought to just bite the bullet though.

 

[cactusman]

I have had the unfortunate circumstance of noticing extra engine noise toward the end of my last flight. Upon post-flight inspection, I found the exhaust loose. When I took off the cowl, I found 3 of the 8 exhaust springs had failed and were gone, leaving my muffler and down pipes severely damaged from excessive vibration. The replacement exhaust (ex-00044) is currently $3150 on vans and that's a significant hit to the budget. I found replacement ball joints and parts on leading edge airfoils, and am considering having a local welder (who I trust with stainless) cut out the old and weld in the new. Parts are $400, not sure about labor costs yet, but likely at least $500 with all the careful alignment required. (Not to mention I don't know when he can get to it)

1. Has anyone done the weld game with this exhaust? If so, any tips/tricks?
2. I've read some about the ex-00044 "upgrade". For those that have it... worth $3k?

Looking forward to any wise counsel as I'm new to the game. Thanks!

There is a pretty extensive Van's S/B about the 3 previous exhaust types and what ones to watch out for - 2 pipes had required replacements. This SB can help you identify which exhaust you actually have:

SB-00005 - Van's Aircraft Total Performance RV Kit Planes

Covers inspection and replacement of two exhaust pipes on Original model RV-12 aircraft. Does not apply to RV-12iS. Supersedes SB 19-03-22.

www.vansaircraft.com

Many of us earlier builders replaced our springs with the stainless steel version and when I do my annual, I remove and inspect and redo the nickel-free joints and then ensure I have fresh hi-temp RTV inside the springs as well as on the connections, as well as a loop of safety wire. There have been many reports of the carbon steel ones breaking.

GPL Stainless Steel Exhaust Spring For 912 Series | Aircraft Spruce

GPL Stainless Steel Exhaust Spring For 912 Series Won't Rust. Lasts for years.

www.aircraftspruce.com