Doghouse baffle for '66 E - owner fab options?

[knute]

My '66 E model has the infamous "doghouse" engine baffling, and after

nearly 47 years (first flight was 11/65, for those doing the math) the

original baffling is not as happy as it once was. I had a good chat

at Oshkosh last week with the foreman from Airforms up in Alaska, and

they have a new doghouse that is currently working its way through the

PMA approval process. In the interim, with some direction from me as

the owner, they suggested that it would be acceptable to do this as an

owner fabricated part. Somebody out there with another E-model is

currently having this very baffle made at Airform, and I will be

receiving pictures by the end of the week to start negotiating with my

MSC to see how willing they might be to install and sign off.

I'd be very interested in finding out about others who have

experienced the process of working with "owner fabricated" parts. I

would love to end up with something that seals better than what I

have, has fewer "patches" and extra screws, and has a nice

powdercoated finish!

(And if you happen to be the other E owner having the baffles made,

please contact me!)

[MooneyMitch]

Knute.  PM me if you would please.

[danb35]

I did my instrument panel upgrade as an owner-produced part, and was far more involved in the design than the regulations require (I actually did the CAD drawing).  Legally, you can give a part to someone else (can be the high school shop teacher next door--doesn't have to hold any FAA certificates or anything), say "make me one just like this", and the resulting part qualifies as an owner-produced part.  The installing mechanic needs to satisfy himself that the part conforms to the type design.  In the case of a baffle part, that would likely mean being made of the same material (alloy and thickness) and fitting the same as the original.  Really, though, you need to discuss this with your A&P.

[sellis]

Quote: danb35

I did my instrument panel upgrade as an owner-produced part, and was far more involved in the design than the regulations require (I actually did the CAD drawing).  Legally, you can give a part to someone else (can be the high school shop teacher next door--doesn't have to hold any FAA certificates or anything), say "make me one just like this", and the resulting part qualifies as an owner-produced part.  The installing mechanic needs to satisfy himself that the part conforms to the type design.  In the case of a baffle part, that would likely mean being made of the same material (alloy and thickness) and fitting the same as the original.  Really, though, you need to discuss this with your A&P.

[knute]

Stacey-

Glad to see you here!  Does Mooney still manufacture or have stock of the doghouse parts for a '66 E?  I had been led to believe the answer is no, but I'd be happy to spend on factory parts if the price isn't stratospheric!

 

[DaV8or]

Quote: sellis

 Be careful just having a part made to look like the original. How do you know the type design? There are more parts then most know that require heat treat, cad plating, chrome plate etc. Instrument panel is not in question here. I'm just saying there a lot of processes done to prevent cracks or other things that Mooney Engineers have determined a needed process be done.

[tomn]

Did you buy the baffles from Airform and if so how did they work out? I have a 66 E that is getting an engine O/H right now and I need to replace the original baffles as well.

On a different note - a cracked oil cooler line is the reason the engine is being overhauled. I have been flying it for about 4 years with an 800 hr motor at the time of the failure. The line developed a leak in flight and pumped all the oil overboard. I was able to get it to an airport but not before destroying the crank and no. 3 rod. I've searched back through the logs and found that the oil lines were 14 years old and had not been replaced when the motor was done 800 hrs ago. Most A&P's I've talked with since suggest replacing about every 8 years but never more than 10. If you are not sure of the age of your hoses - find out - its important to know for yourself.

Tom

[Alan Fox]

My B had the infamous dog house , Just remove the cover , and save 1 piece of the assy , like one of the vents that cool the mags....I made it in two hours and it worked great , Im guessing the top cover failed as that is the weak point....

[1964-M20E]

Airforms does a good job. I repalced mine with airforms. i did develope cracks on some parts and he replaced them. Watch for stress when you install the new baffles.

[tomn]

I think I will give Airforms a try. I'll post how it works out.

[knute]

That's good advice on the oil cooler lines- thanks.

I didn't end up purchasing the Airforms baffles this year, but I continue to want them- ran out of lead time before annual and then budget on this go around. An expensively thorough annual this year included oversized nose gear bushings, new nose gear shock disks, "new" muffler (Dawley), new oil cooler, new alternator, two new magnetos, cylinder work due to a valve problem on #3 (root cause- poor workmanship from a prior engine shop), gascolator overhaul, etc. The plane is now purring, but I'm sure my speed increase is partly due to the weight reduction of my wallet. :-) We sealed up the existing factory baffles and put them back to work, but I'm pretty sure the Airforms baffles will eventually find a home on my engine.

Those of you who get them before I do, please post PIREPs!

Did you buy the baffles from Airform and if so how did they work out? I have a 66 E that is getting an engine O/H right now and I need to replace the original baffles as well.

On a different note - a cracked oil cooler line is the reason the engine is being overhauled. I have been flying it for about 4 years with an 800 hr motor at the time of the failure. The line developed a leak in flight and pumped all the oil overboard. I was able to get it to an airport but not before destroying the crank and no. 3 rod. I've searched back through the logs and found that the oil lines were 14 years old and had not been replaced when the motor was done 800 hrs ago. Most A&P's I've talked with since suggest replacing about every 8 years but never more than 10. If you are not sure of the age of your hoses - find out - its important to know for yourself.

Tom

[Sabremech]

Manufacturing or making owner produced parts can be done to original specifications. The easiest way is to have a drawing, but most likely won't happen as Mooney is still in the business of making parts. As long as an original can be found, it can be sent out for metal analysis and then reproduced. Mooney engineers designed it, but it can be reverse engineered to an original specification and produced as an FAA/PMA or owner produced part.