Leading Edge Exhaust Updates

[Darrel Starr]

I had not connected with Dane Wagner at Leading Edge Exhaust since 2005 but a crack in my LEE muffler (caused by the Overboard/Tail Pipe vibrating against the firewall) led to me call him. Dane has made a number of improvements in the system.
Jay Stanford in Georgia PMd me after I published a picture of the cracked muffler to offer up one he had in stock. So I bought it knowing it was an early LEE muffler manufactured in Dec. 2001 but with just 40 hrs on it.
It needed the updates that I already knew about dating back to 2003 – 2005:

1. Close down the slits in the muffler stub pipes where the riser pipes enter. Weld the slits so they are no more than ½ inch long.

1. Check the stub pipes for correct sizing so the riser pipes fit snugly but insert to the full extent. I had Aerospace Welding expand the tubes – they did it while I waited, about 20 minutes.
2. To eliminate weld cracking, cut the welds on one of the “U” channel spacers and weld on tabs to trap the “U” channel in place.

These changes were well known years ago but if you haven’t updated your older LEE system it would be wise to do so.
The newer changes that I was not aware of include:

1. The availability of a doubler from LEE to bridge across the weld that cracked in my muffler. There last installation update “Rev H” dated 2006 warns of Overboard Pipes vibrating against cowling causing 4 cracked mufflers at that point in time.

By the time Bob Eckstein, IA and expert Welder , and I knew about the LEE doubler, we had designed and welded our own diamond shaped doubler.
LEE Doubler

Eckstein/Starr Doubler

1. An improved T-Bolt clamp for the muffler-to-riser pipes is available. Dane has recently gone to a slightly smaller version of this Dixon brand clamp and didn’t have the new ones in yet so I used Super Trapp 094-1750 Clamps from Summit Racing, about $12 each.

1. Another improvement that I have not made (yet anyway) is a separate cuff on the #3 riser pipe to provide carburetor heat called the Carburetor Heat Fitting (CAHF), separating it from the rear seat outlet. That would eliminate the rear seat heater placard that forbids use of both the rear seat heat and carb heat at the same time

1. There are some Overboard Pipe changes also, a change to the angle I think. In order to blow the exhaust further from my bungee covers, I had Aerospace Welding make up a 17 inch long Overboard Pipe with a straight cut end. I had a local ceramic coating outfit apply a chrome like coating, $35, which I hope will not discolor.

It is all back together and signed off. Plan to fly this weekend.

 

[Darrel Starr]

More photos
Here is the carburetor Heat Fitting - CAHF

And here is the 17 inch Overboard Pipe: