172E Project

D

DB1

Filing Flight Plan
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Dave
Hi guys,
I'm new here, but have been lurking for a while. Looks like a great forum with lots of valuable info. Here's some background on me, then my questions. I'm an A&P with IA. Also a Commercial SEL, SES, MEL currently working for a part 135 operation in New England. Used to fly full time and wrench part time, but since pilots are a dime-a-dozen, and A&Ps harder to come by (good ones anyway) I now wrench full time and fly part time. :p Works for me, as I like wrenching about as much as I like flying.

Anyway, my partner and I bought a project 172E. Sat in a hangar for several years, but airframe's in good shape. TT airframe and engine is about 1300hrs. Got it for a great price, complete with a hangar, spare Cessna heavy duty nose gear, and core C-142-2 engine. We decided to overhaul the engine, since this is intended to be a fix it and flip it project. Disassembled it, sent out all the steel parts and case to be NDTed. All came back yellow tagged. The one problem is the cylinders. I'd like to either overhaul the ones we have, or buy new, but we'll be looking at around $6,000 either way. This is an O-300-D, BTW.

We just don't have the money for that, so we're thinking of doing the cylinders ourselves by honing, lapping the valves, new rings, dimensional checks, inspection and calling it good. My partner says that will constitute an overhaul of the cylinders, but from looking at the SB from Continental they require a whole lot of parts to be replaced, such as guides, exhaust valves, etc. So, my question is: what will be the correct way to sign off the log entry? List the work performed and call it a repair, or is my partner correct, and that SB is not required to be C/W to call the cylinders overhauled? If the lower end meets the requirements of overhaul, but the top end doesn't my guess is that the engine can only be called "repair."

Sorry for the long post. Thanks in advance, and feel free to give me grief!
 
DB1 said:
Hi guys,
I'm new here, but have been lurking for a while. Looks like a great forum with lots of valuable info. Here's some background on me, then my questions. I'm an A&P with IA. Also a Commercial SEL, SES, MEL currently working for a part 135 operation in New England. Used to fly full time and wrench part time, but since pilots are a dime-a-dozen, and A&Ps harder to come by (good ones anyway) I now wrench full time and fly part time. :p Works for me, as I like wrenching about as much as I like flying.

Anyway, my partner and I bought a project 172E. Sat in a hangar for several years, but airframe's in good shape. TT airframe and engine is about 1300hrs. Got it for a great price, complete with a hangar, spare Cessna heavy duty nose gear, and core C-142-2 engine. We decided to overhaul the engine, since this is intended to be a fix it and flip it project. Disassembled it, sent out all the steel parts and case to be NDTed. All came back yellow tagged. The one problem is the cylinders. I'd like to either overhaul the ones we have, or buy new, but we'll be looking at around $6,000 either way. This is an O-300-D, BTW.

We just don't have the money for that, so we're thinking of doing the cylinders ourselves by honing, lapping the valves, new rings, dimensional checks, inspection and calling it good. My partner says that will constitute an overhaul of the cylinders, but from looking at the SB from Continental they require a whole lot of parts to be replaced, such as guides, exhaust valves, etc. So, my question is: what will be the correct way to sign off the log entry? List the work performed and call it a repair, or is my partner correct, and that SB is not required to be C/W to call the cylinders overhauled? If the lower end meets the requirements of overhaul, but the top end doesn't my guess is that the engine can only be called "repair."

Sorry for the long post. Thanks in advance, and feel free to give me grief!
Click to expand...

The only thing that really matters is, can you comply with FAR 43.2? Service bulletins are not compulsory in Part 91, only the requirements of FAR 43.2.
 
Would you want your name on the overhaul that has continual cylinder problems? Do you know how many hours are on the cylinders? We have proven that the OEM factory cylinder will crack from the exhaust valve to the spark plug hole at about 3000 hour TT.

I quit doing cylinders a long time ago. New ones are the best money you can spend.

In the resent past the Chinese bought TCM, Superior, And ECI. We are yet to see which of the three will be producing the cylinders for TCM.
or if they will continue to build under all three names from one factory.

Who did your machine work?
 
As far as complying with 43.2, yes this engine will comply.

The whole engine, including cylinders has approx. 1300hrs TTSN. I have the complete logs, and verified that these are the original cylinders.

I knew the commies bought TCM and ECI, and recently found out that ECI no longer makes cylinders (at least not for the O-300s.) Superior is still making them but you have to order new cylinders in advance as they can't keep up with demand. New options are TCM for about $1000 each or back order Superiors for about $900 each.

We sent the case to Crankshaft services in OK, cam to aircraft specialties, and the rest to Aerotec Engines in Nova Scotia, CA.
 
DB1 said:
As far as complying with 43.2, yes this engine will comply.

The whole engine, including cylinders has approx. 1300hrs TTSN. I have the complete logs, and verified that these are the original cylinders.

I knew the commies bought TCM and ECI, and recently found out that ECI no longer makes cylinders (at least not for the O-300s.) Superior is still making them but you have to order new cylinders in advance as they can't keep up with demand. New options are TCM for about $1000 each or back order Superiors for about $900 each.

We sent the case to Crankshaft services in OK, cam to aircraft specialties, and the rest to Aerotec Engines in Nova Scotia, CA.
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I knew that ECI would make a big difference if they quit. Pretty sad, Those were great cylinders.
I see that Aircraft specialities have a top overhaul kit for $6400+ I wonder what cylinders they provide in that kit? or if the wait list applies?
Overhauling your cylinders, I'd replace the guides and valves plus a hone 5 over with new pistons/ring sets.
 
Whether you can get away with honing the cylinders depends on how out of round and worn they are, doesn't it??
 
About 45 years (!) ago we overhauled a '67 172H with 1060 hrs SNew on the O-300D engine. The jugs had obviously been made and sized as pure cylinders by Continental with a slight choke at the tops of the bore that was gotten by shrinking the head on when it was new. We ended up grinding every one .015 over as I recall, putting in new OS pistons and valve guides. It ran over 1600 hrs additional without trouble before I lost track of it.

The front flange on the crank was cracked & we ended up buying a new one in 1971 for $1060!

Very old data but relevant to your situation.
 
coloradobluesky said:
Whether you can get away with honing the cylinders depends on how out of round and worn they are, doesn't it??
Click to expand...
I've yet to see a 0-200/0-300 cylinder with 1300 hours that will be with in standard dimensions or at service limits. You are allowed to have .038" between the piston skirt and the cylinder wall, at 1300 hours you'll be beyond that.
 
It requires some very spendy equipment to bore an aircraft cylinder, that equipment isn't usually found in the average A&P's truck :)
 
Tom-D said:
I've yet to see a 0-200/0-300 cylinder with 1300 hours that will be with in standard dimensions or at service limits. You are allowed to have .038" between the piston skirt and the cylinder wall, at 1300 hours you'll be beyond that.
Click to expand...

That's why we're thinking of using the cylinders off the C-145 we have. They only have 300 some odd hours TT. As for the equipment to do the cylinders, my partner used to be DOM of a Cessna Service center in the area and has built up some good connections over the years. He has access to the equipment we will use.
So, would the general consensus be that we can call the cylinders overhauled if all parts are with tolerances, even if we don't replace valves and guides unless needed? The SB# is SB97-6B for those interested.
Thank you to everyone for the valuable info, I really appreciate it.
 
DB1 said:
That's why we're thinking of using the cylinders off the C-145 we have. They only have 300 some odd hours TT. As for the equipment to do the cylinders, my partner used to be DOM of a Cessna Service center in the area and has built up some good connections over the years. He has access to the equipment we will use.
So, would the general consensus be that we can call the cylinders overhauled if all parts are with tolerances, even if we don't replace valves and guides unless needed? The SB# is SB97-6B for those interested.
Thank you to everyone for the valuable info, I really appreciate it.
Click to expand...
IAW FAR 43.2 you don't have to replace any thing to call it overhauled.
 
Tom-D said:
IAW FAR 43.2 you don't have to replace any thing to call it overhauled.
Click to expand...
so....what would Tom do?....besides buy everything new? :D

I'm thinking if one were to measure those cylinders (they're not life limited)....and if they met the conditions of the OH manual....they'd be fine.
 
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So here's a question. If I overhaul the engine, including cylinders IAW 43.2, what would be the "methods, techniques, and practices acceptable to the Administrator" that I would use? If it's the engines MM, would that also have to include SB97-6B "Mandatory Replacement Parts", since that SB is FAA Approved? Not trying to argue, just want to make sure I'm not lining myself up for trouble with the FAA in the future.
 
DB1 said:
So here's a question. If I overhaul the engine, including cylinders IAW 43.2, what would be the "methods, techniques, and practices acceptable to the Administrator" that I would use? If it's the engines MM, would that also have to include SB97-6B "Mandatory Replacement Parts", since that SB is FAA Approved? Not trying to argue, just want to make sure I'm not lining myself up for trouble with the FAA in the future.
Click to expand...
Boring cylinders is an excepted practice as per the 0-300 MM fitting new parts as required is IAW the 43.2
I don't see your problem. send the cylinders out to a shop that has the acceptable methods as required, return to you for assembly with new parts as required.
 
Checkout_my_Six said:
so....what would Tom do?....besides buy everything new? :D

I'm thinking if one were to measure those cylinders (they're not life limited)....and if they met the conditions of the OH manual....they'd be fine.
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Every one know I prefer to put as many new parts in a rebuild as possible. To me its common sense the closer to new the engine is the longer it will last.
It is perfectly legal to overhaul cylinders, I did it for many years, but when better cylinders were available why would you do it? but now we may be back to doing it simply because of ECI going out of business and the long wait for Superior's deliver.
but with cost of 1000 per cylinder from TCM plus the other machining costs plus the shipping and new lower and parts the Tom Anderson up grade to the IO-360- may be a better option.
 
DB1 said:
So here's a question. If I overhaul the engine, including cylinders IAW 43.2, what would be the "methods, techniques, and practices acceptable to the Administrator" that I would use? If it's the engines MM, would that also have to include SB97-6B "Mandatory Replacement Parts", since that SB is FAA Approved? Not trying to argue, just want to make sure I'm not lining myself up for trouble with the FAA in the future.
Click to expand...
I'm thinking the engine Over Haul manual is what needs to be followed.....to serviceable tolerances....for it to be considered an OH.
 
Checkout_my_Six said:
I'm thinking the engine Over Haul manual is what needs to be followed.....to serviceable tolerances....for it to be considered an OH.
Click to expand...
That's not what FAR 43.2 says.

43.2 Records of overhaul and rebuilding.

(a) No person may describe in any required maintenance entry or form an aircraft, airframe, aircraft engine, propeller, appliance, or component part as being overhauled unless—
(1) Using methods, techniques, and practices acceptable to the Administrator, it has been disassembled, cleaned, inspected, repaired as necessary, and reassembled; and
(2) It has been tested in accordance with approved standards and technical data, or in accordance with current standards and technical data acceptable to the Administrator, which have been developed and documented by the holder of the type certificate, supplemental type certificate, or a material, part, process, or appliance approval under part 21 of this chapter.
(b) No person may describe in any required maintenance entry or form an aircraft, airframe, aircraft engine, propeller, appliance, or component part as being rebuilt unless it has been disassembled, cleaned, inspected, repaired as necessary, reassembled, and tested to the same tolerances and limits as a new item, using either new parts or used parts that either conform to new part tolerances and limits or to approved oversized or undersized dimensions.
 
Can he call his engine rebuilt?
 
Serviceable parts meet para (a) requirements.
Tom-D said:
That's not what FAR 43.2 says.

43.2 Records of overhaul and rebuilding.

(a) No person may describe in any required maintenance entry or form an aircraft, airframe, aircraft engine, propeller, appliance, or component part as being overhauled unless—
(1) Using methods, techniques, and practices acceptable to the Administrator, it has been disassembled, cleaned, inspected, repaired as necessary, and reassembled; and
(2) It has been tested in accordance with approved standards and technical data, or in accordance with current standards and technical data acceptable to the Administrator, which have been developed and documented by the holder of the type certificate, supplemental type certificate, or a material, part, process, or appliance approval under part 21 of this chapter.
(b) No person may describe in any required maintenance entry or form an aircraft, airframe, aircraft engine, propeller, appliance, or component part as being rebuilt unless it has been disassembled, cleaned, inspected, repaired as necessary, reassembled, and tested to the same tolerances and limits as a new item, using either new parts or used parts that either conform to new part tolerances and limits or to approved oversized or undersized dimensions.
Click to expand...
 
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