CO level in cabin

[Jinkers]

The exhaust pipe extension worked. Now just have to figure out how to do it permenantly and leagally.

[Steve Pierce]

I sent a tail pipe to Dawley and told them I wanted it X" longer and they built me one.

[Tadpole]

The exhaust pipe extension worked. Now just have to figure out how to do it permenantly and leagally.

That's great to hear! I still need to get up to Greely for a visit one of these days.

[Stephen]

I sent a tail pipe to Dawley and told them I wanted it X" longer and they built me one.

It seems to me that an A&P could have a 3 ro 4 inch extension welded on as a minor modification and entered as a log book entry.

[Jinkers]

I sent a tail pipe to Dawley and told them I wanted it X" longer and they built me one.

It seems to me that an A&P could have a 3 ro 4 inch extension welded on as a minor modification and entered as a log book entry.

That's probably the answer. I talked with my A&P and he is going to look into whether or not it will just take a log book entry or a field approval. He did suggest that first we cut an inch at a time off of the extension and see how long it rally needs to be. He thinks that the extension that I put on is probably longer then it needs to be.

[smcnutt]

Just curious how far does the extension/tailpipe extend past the cowl? As usual, pictures would be great.

[Jinkers]

Just curious how far does the extension/tailpipe extend past the cowl? As usual, pictures would be great.

Here is a picture that shows how far the original exhaust extended past the Cowl. I added a 6" turndown exhaust extension from an auto parts store. I'll take a picture of it with the extension next time I'm out at the hanger.

[Jinkers]

Did some testing today. The extension I started with was 6" and there was no rise in CO levels. I cut it down to 5" then 4" and still no rise in CO levels. At 3" the CO levels started to rise from an ambient reading of 8 up to the mid-teens. So, 4" it is. My A&E is just going to replace the original 16" exhaust pipe with a 20" pipe and get a field approval.

Here are pictures of the original exhaust and a picture with 4" extension:


Thanks all for the help

[Clipper Driver]

When I purchased my Clipper about two years ago, it had what appeared to be a short automotive exhaust pipe pressed in place over the end of the tailpipe to increase the length. Recently, it started to corrode very badly. I was able to pull it off by hand, and it virtually crumbled as I did so. The only thing holding it together was the plating. The tailpipe has a few small holes near the end, but appears serviceable otherwise. The tailpipe with and without extension look very similar to the previous post by Scott.

Before flying again, I called the previous owner and asked him if he thought it would be okay to fly without the extension. He said he had flown the plane several years before installing the extension, and had no problems during that time. He said he had a CO detector – I think one of the cheap ones where a dot turns colors – and had no indication of exhaust getting in the cockpit. I then flew the plane for several hours, carefully watching the CO detector (mine is also one of the cheap ones). There was no indication of a problem or any change from flying with an extension. I will borrow my friend’s portable electronic CO detector and fly with that to be sure.

Even if everything is fine, an extension still seems like a good idea. The exhaust doesn’t pass very far below the sheet metal covering the landing gear. I have another extension identical to the one I removed, but I am reluctant to install it due to weight and short life. So, I’m thinking I would like to get a new tailpipe, but several inches longer than standard, and I would like a bale at the top to prevent any internal muffler parts from restricting the tailpipe opening if they should break loose.

Questions:

Is the automotive extension an acceptable way to go? (The extension I have is 8.5-inches long. The upper part that slips over the existing tailpipe is 2.5-inches long, 2.125- inch OD with a 0.06-inch wall. The necked down part is 2-inch OD with a 0.05-inch wall and a 45 degree bevel at the end.)

Is there anyplace I can get a tailpipe that is several inches longer than standard, and with a bale at the top? (The aircraft parts place I go to says they work with an aircraft exhaust system that will weld up whatever I want, so that’s an option too. But, I would probably have to remove my tailpipe, make a drawing, and wait for it to be made. No telling what the turn-around time would be.)

Thanks in advance for any help or advice!

[Steve Pierce]

Seen the automotive chrome tips used on several airplanes with the same rusting problems you have experienced. As I posted above I sent an old tailpipe to Dawley and had them make it longer. Works perfectly at getting the exhaust out away from the belly though someone commented that it is slowing me down.