Exhaust repair

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jesse

Touchdown! Greaser!
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Jesse
Recently it seemed like carbon monoxide was becoming an issue in the Flybaby. This evening I had time to tackle it, I started by hooking the shop vac up to the exhaust pipe and blowing air into it. It became very obvious that there was a leak.

I believe the cracks to be mostly contained to this area on both sides of the muffler. But hell, there could be more, I haven't had time to inspect is too closely yet:
BSXs2.jpg


The heat shroud is also corroded in a less than ideal way:
ab8cp.jpg


Any suggestions as to the best people to repair/overhaul/whatever this? Any clue what it'll cost? I believe it to be a J3 exhaust
 
So with that Wag Aero one I can ship them the muffler, heat shrouds, and headers and they'll fix all of it for that price?
 
Jesse:

I used Dawley, and they repaired both of my exhaust stacks and one muffler quickly, for less $$ than they quoted over the phone. Stuff looked like new.

Guy I know sent them a muffler from a 150 to be "repaired - he told me that the muffler he sent them was so corroded, he could literally stick a pencil through the side (and did!). What came back looked like new.

I was completely satisfied. http://www.dawleyaviation.com/
 
SCCutler said:
Jesse:

I used Dawley, and they repaired both of my exhaust stacks and one muffler quickly, for less $$ than they quoted over the phone. Stuff looked like new.

Guy I know sent them a muffler from a 150 to be "repaired - he told me that the muffler he sent them was so corroded, he could literally stick a pencil through the side (and did!). What came back looked like new.

I was completely satisfied. http://www.dawleyaviation.com/
Click to expand...

They are good company too.
 
jesse said:
Recently it seemed like carbon monoxide was becoming an issue in the Flybaby. This evening I had time to tackle it, I started by hooking the shop vac up to the exhaust pipe and blowing air into it. It became very obvious that there was a leak.

I believe the cracks to be mostly contained to this area on both sides of the muffler. But hell, there could be more, I haven't had time to inspect is too closely yet:

Any suggestions as to the best people to repair/overhaul/whatever this? Any clue what it'll cost? I believe it to be a J3 exhaust
Click to expand...
Damn, it must be catching...I ended up with leaks in my Fly Baby's heat exchanger, too. A&P suggested I do a leak test, but just removing the shroud indicated something was wrong:
annual_1.jpg

The muffler has a bulkhead across the middle dividing the carb and cabin heat portions; the weld on the tailpipe fitting cracked and had been gassing up the carb heat side. So that side is all sooted up, and the cabin heat side was still pristine.

You can see how the weld cracked here:
annual_3.jpg


Been two months, and I'm just on the verge of getting it flying again. I dropped off the parts at my favorite welder, and he seemed to disappear. Turns out he had several stints in the hospital. Got the parts back and installed, and am just waiting for the A&P signoff on the Condition inspection.

One problem I had: The flanges on my headers were warped, and I bought brand-new ones from Aircraft Spruce and held the welder replace the old ones. The problem is, the new flanges are a bit wider than the old ones...I had to use a grinder to get them carved down enough to fit.

Also, when you get the muffler back, re-do the leak test prior to installation. Mine had developed some fine cracks during the welding process, and I had to have them fixed, too.

Jesse, Harry Fenton recommended a welder for exhaust repairs... I'll PM his contact info.

Ron Wanttaja
 
So Jesse, glad you caught this. How did you determine there was a problem? CO monitor? Exhaust smell in the cockpit?
 
Ahh, the joys of experimental. I do hope you can get it patched up quick Jessie.
 
Gald you caught it, Jesse :)
Dawley is my "Package and send it" choice, but Ron is right, test it when you get the stuff back....
 
I've been using Knisley since the 80's with nary a problem. The stuff they make is almost too pretty to waste on an airplane exhaust system.
 
The parts you get from Knisley, Dawley and AWI are new parts with paperwork that states 'repair'.
 
Obviously of no help to you, but while on the subject of "Exhaust," I have a muffler for a Lycoming 0320-E2d engine. It had passed Annual inspection but was removed when I had the Powerflow Tuned Exhaust installed. Attached to it is the Carb-heat Box. It's available if anyone needs a replacement for the above engine.
(Pictures, if requested)

HR
 
weilke said:
The parts you get from Knisley, Dawley and AWI are new parts with paperwork that states 'repair'.
Click to expand...

An A&P with whom I am acquainted speculates that these shops take a shred of the old exhaust component, attach it to the new part (thus "repairing" the old one), then grind off or otherwise remove the rusty old shred, and ship out the thus-"repaired" part.

Maybe something do with the difference between a Repair Station and a PMA manufacturer? Common-sense, in any event.
 
steingar said:
Ahh, the joys of experimental. I do hope you can get it patched up quick Jessie.
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Out of curiousity, how does it being "Experimental" factor into it?

From the pictures, it looks like Jesse has an exhaust system very similar to mine, and mine is the same one used on a number of production-type aircraft. Jesse isn't the builder, nor was the previous owner, so the airplane has undergone annual condition inspections to the same level of detail as production aircraft since at least 2007, by a licensed A&P. So Jesse is no better or worse off than if he owned a Champ or a Super Cub.

Ron Wanttaja
 
fwiw - here's another vote for Dawley.
 
SCCutler said:
An A&P with whom I am acquainted speculates that these shops take a shred of the old exhaust component, attach it to the new part (thus "repairing" the old one), then grind off or otherwise remove the rusty old shred, and ship out the thus-"repaired" part.
Click to expand...

Something like that.

Maybe something do with the difference between a Repair Station and a PMA manufacturer? Common-sense, in any event.
Click to expand...

The way it was explained to me:
- to call a part 'new', you need a PMA or STC (they have pmas for some exhaust components)
- to call a part 'overhauled', there has to be an 'overhaul manual' from the exhausts manufacturer available. No such manual exists.
- to call it 'repaired', you can replace pretty much every molecule of the part as long as what you return conforms to the specs and drawings of what you were provided with.
 
wanttaja said:
Out of curiousity, how does it being "Experimental" factor into it?

From the pictures, it looks like Jesse has an exhaust system very similar to mine, and mine is the same one used on a number of production-type aircraft. Jesse isn't the builder, nor was the previous owner, so the airplane has undergone annual condition inspections to the same level of detail as production aircraft since at least 2007, by a licensed A&P. So Jesse is no better or worse off than if he owned a Champ or a Super Cub.

Ron Wanttaja
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I took it to mean he can do at least some of the repair work himself.
 
wanttaja said:
Out of curiousity, how does it being "Experimental" factor into it?
Click to expand...

If mine breaks I don't have to go through all this to get a new one. I've never before had to go to any length at all to get parts.

There is the advantage that one can effect repair oneself, provided one is good at welding and metal working. I suppose such repairs have to go through some sort of approved process for certificated parts that involves the input of gobs of money, which the experimental folks can adroitly avoid.

All that said, my aircraft has never been in the shop for months because someone was sick.
 
wanttaja said:
Out of curiousity, how does it being "Experimental" factor into it?
Ron Wanttaja
Click to expand...

easy.... you don't have any return to service requirements.

wire two tomato cans on there you are good to go.
 
Fact... EXP aircraft do not need data tags on parts, thus any shop can make the whole thing from scratch, no turn in required.

your local muffler shop can build one for you, If your local A&P does not like it, ask why, what FAR can he use to say it is unairworthy.

your letter of limitations ? nope that will tell you nothing about replacement parts.

If the aircraft meets its letter of limitations, he must sign the conditional inspection as completed, he does not need to place a statement as to the airworthiness.

"I have inspected this aircraft IAW its letter of limitations and find that it meets those requirements"

That is all the return to service needs to say.
 
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steingar said:
There is the advantage that one can effect repair oneself, provided one is good at welding and metal working. I suppose such repairs have to go through some sort of approved process for certificated parts that involves the input of gobs of money, which the experimental folks can adroitly avoid.

All that said, my aircraft has never been in the shop for months because someone was sick.
Click to expand...

I suspect few owners of homebuilts...especially those who buy their planes, like Jesse and I... do welding repairs themselves. So for the most part, we're stuck with the same shops the certified folks use.

As for waiting for the parts because someone was sick, the shop was formerly an FAA-approved repair station. The guy got tired of the red tape. So my experience probably isn't out of the question for the certified folks, either.

Total calendar time from drop-off to picking up the parts, even with the illness, was about six weeks. The shop is 10-minutes drive from where I work, so there wasn't any wait (or cost...) of shipping. It was nice to both be able to look at the parts and discuss options.

Ron Wanttaja
 
steingar said:
If mine breaks I don't have to go through all this to get a new one. I've never before had to go to any length at all to get parts.

There is the advantage that one can effect repair oneself, provided one is good at welding and metal working. I suppose such repairs have to go through some sort of approved process for certificated parts that involves the input of gobs of money, which the experimental folks can adroitly avoid.

All that said, my aircraft has never been in the shop for months because someone was sick.
Click to expand...

You'd be going through the same exact thing as I am -- except you'd have less options and you wouldn't be able to do it yourself.

The exhaust is the same thing as a J3 Cub so it's not an extremely rare part. I can either have it rebuilt, or I can buy a new cub exhaust, or I can take it down to any muffler shop and have them rebuild it.

My engine more or less is the same as it would be certified and is maintained to certified standards more or less...so I'll be having an aircraft exhaust shop rebuild it just as they would if it were on a certified Cub.

I suspected an exhaust leak, I tested and verified there was a leak, I then yanked the exhaust off and will send it for repair. Once I get it back I put it back on. Much easier then it would be if I owned your certified airplane.

Like any machine I've ever owned if it breaks I fix it. If I don't feel I can fix it then I get help from those that know more.

The way the Flybaby sits right now:
66361_3794393539784_1589030453_n.jpg
 
wanttaja said:
I suspect few owners of homebuilts...especially those who buy their planes, like Jesse and I... do welding repairs themselves. So for the most part, we're stuck with the same shops the certified folks use.
Ron Wanttaja
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Not really, you can use the local muffler shop.
 
jesse said:
The exhaust is the same thing as a J3 Cub so it's not an extremely rare part. I can either have it rebuilt, or I can buy a new cub exhaust, or I can take it down to any muffler shop and have them rebuild it.
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And that is what I would do, the aircraft repair shop is held to a standard, your local muffler shop can make it better. :)
 
AdamZ said:
So Jesse, glad you caught this. How did you determine there was a problem? CO monitor? Exhaust smell in the cockpit?
Click to expand...

There is a household electronic CO monitor mounted on the sidewall of the airplane inside the cockpit.

I've thought it kind of strange how "tired" I feel after three hour legs in that airplane. But I confirmed the CO detector was working so I didn't think much of it.

Well on the last few flights I've noticed that when I pull the power off in a long descent coming into an airport the CO monitor starts going off. I started to think it might have something to do with the airflow in descents coming in some of the gaps between the windshield and canopy.

Well the other day it finally dawned on me that it's probably going off the entire time and I just can't hear it when I have the power on. It turns out that is what was happening..the damn thing has been going off non-stop in cruise at least on the last two flights.

So I quit flying it until I had time to look into where the CO was coming from. Last night I had a free few hours so I hooked my shop vac up to the exhaust pipe in BLOW mode and sealed it with some duct tape. Hit the button..and boom I could feel leaks coming out all over the place. I then decided I needed to rip the entire exhaust off to inspect/repair as necessary..
 
Tom-D said:
Fact... EXP aircraft do not need data tags on parts, thus any shop can make the whole thing from scratch, no turn in required.

your local muffler shop can build one for you, If your local A&P does not like it, ask why, what FAR can he use to say it is unairworthy.

your letter of limitations ? nope that will tell you nothing about replacement parts.

If the aircraft meets its letter of limitations, he must sign the conditional inspection as completed, he does not need to place a statement as to the airworthiness.

"I have inspected this aircraft IAW its letter of limitations and find that it meets those requirements"

That is all the return to service needs to say.
Click to expand...

My Operating Limitations require a yearly conditional inspection to the scope and breadth of Appendix D of 14CFR Part 43. The Appendix requires that the A&P inspect the exhaust stacks for "cracks, defects, and improper attachment." Seems to me that the A&P has grounds for refusing to sign off the conditional inspection if he believes the parts used aren't of sufficient quality.

Otherwise, I could have just told him to ignore the cracked muffler and sign off the damn airplane. :)

Ron Wanttaja
 
jesse said:
The exhaust is the same thing as a J3 Cub so it's not an extremely rare part. I can either have it rebuilt, or I can buy a new cub exhaust, or I can take it down to any muffler shop and have them rebuild it.
Click to expand...
Jesse, I can't tell if you've got an A65 or not; if so, a Cub exhaust is fine. They'll work on C85s as well, BUT the pipes have to be extended a bit because of the accessory case. So if you've got a C85 and decide to go all-new, keep that in mind.

This is the second repair of my exhaust system (the last one was ~10 years ago, different issues) and if it has problems again, I'm going to spring for a new one.

Ron Wanttaja
 
wanttaja said:
My Operating Limitations require a yearly conditional inspection to the scope and breadth of Appendix D of 14CFR Part 43. The Appendix requires that the A&P inspect the exhaust stacks for "cracks, defects, and improper attachment." Seems to me that the A&P has grounds for refusing to sign off the conditional inspection if he believes the parts used aren't of sufficient quality.

Otherwise, I could have just told him to ignore the cracked muffler and sign off the damn airplane. :)

Ron Wanttaja
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The A&P can not set standards on EXP parts, he has no airworthiness standards to comply with.
Remember these are home built, how does he know they were not built that way?

All he can say is I'm not going to put my name on that. legally that is all he can do.

All he is doing on conditional inspection is saying this aircraft is still in compliance with the letter of limitations as equipped. there is no requirement for it to be airworthy, because there is no standard of airworthiness for A/HB
 
wanttaja said:
My Operating Limitations require a yearly conditional inspection to the scope and breadth of Appendix D of 14CFR Part 43. The Appendix requires that the A&P inspect the exhaust stacks for "cracks, defects, and improper attachment." Seems to me that the A&P has grounds for refusing to sign off the conditional inspection if he believes the parts used aren't of sufficient quality.

Otherwise, I could have just told him to ignore the cracked muffler and sign off the damn airplane. :)

Ron Wanttaja
Click to expand...

He can not refuse to sign off any work he completed, he must enter the inspection and say if it was completed or not, and if it was not why it was stopped.

FAR 43.5 makes no exception for A/HB the entries must be made, in a compliance with FAR 43.

and to add insult to the mess, he has no preformance rules other than what the letter of limitations requires. because FAR 43.15 does not apply, simply because of the exception in FAR 91.410. read it, your conditional inspection is not one called out in FAR 91.
 
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Tom-D said:
The A&P can not set standards on EXP parts, he has no airworthiness standards to comply with.
Remember these are home built, how does he know they were not built that way?

All he can say is I'm not going to put my name on that. legally that is all he can do.
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You may get A&P services for free, but I don't. To me it's a Bad Thing if the mechanic won't sign off on the conditional inspection. It costs me money and doesn't result in an airplane I can fly. Because of this, I am greatly motivated to present the guy with an airplane that he feels comfortable in signing off. If that means spending $300 on welding instead of cobbling together tomato cans and duct tape, so be it.

Got a new A&P this time around, and he's being really cautious. Can't really argue, since his request I do a leak check on my exhaust revealed the bad welds.

We're having a good-natured argument right now, over a fairly trivial matter. I can easily make the change he wants, but think the way I have it is actually better in the long run. But it *is* his call, and if he ultimately wants it his way, I can do it in two minutes.

Tom-D said:
All he is doing on conditional inspection is saying this aircraft is still in compliance with the letter of limitations as equipped. there is no requirement for it to be airworthy, because there is no standard of airworthiness for A/HB
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Yep, fully agree with you, there. But it's good peace of mind when the "pro" buys off, especially when he's being strict like my new guy.

Ron Wanttaja
 
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I just shipped the entire exhaust system to Dawley Aviation http://www.dawleyaviation.com/ as per the above recommendations. I took "before" pictures. When I get it back I'll post "before" and "after" pics.
 
Dawley called me today -- said nothing is really worth repairing and they'd rather just build a new one. It's going to run me about $1400 --- ouch. Probably $1500 after shipping both ways.
 
jesse said:
Dawley called me today -- said nothing is really worth repairing and they'd rather just build a new one. It's going to run me about $1400 --- ouch. Probably $1500 after shipping both ways.
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Your local muffler shop is looking better ?????

you can design a new exhaust system and have them weld it together.
 
Wow that must have been pretty bad. Jess would it be less expensive to buy a J-3 exhaust from an aircraft salvage yard? I have not clue what a good used one would cost.
 
Tom-D said:
Your local muffler shop is looking better ?????

you can design a new exhaust system and have them weld it together.
Click to expand...


Agreed 100%......

Jesse's plane is an experimental....
 
wanttaja said:
You may get A&P services for free, but I don't. To me it's a Bad Thing if the mechanic won't sign off on the conditional inspection. It costs me money and doesn't result in an airplane I can fly. Because of this, I am greatly motivated to present the guy with an airplane that he feels comfortable in signing off. If that means spending $300 on welding instead of cobbling together tomato cans and duct tape, so be it.
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My point was you have no airworthiness requirements, that said safe is always good. but you can design and run any thing you like on a home built EXP aircraft.

wanttaja said:
Got a new A&P this time around, and he's being really cautious. Can't really argue, since his request I do a leak check on my exhaust revealed the bad welds.
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exhaust leaks are never good and a pressure check is the way to find leaks, and that is a required inspection IAW 43-D. so he is well with in safe and prudent to do the check.

wanttaja said:
we are having a good-natured argument right now, over a fairly trivial matter. I can easily make the change he wants, but think the way I have it is actually better in the long run. But it *is* his call, and if he ultimately wants it his way, I can do it in two minutes.
Ron Wanttaja
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And you can change it back after he signs off and there is nothing he legally do about it, except tell you to go away next year.
 
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