My engine fell out

idahoflier said:
Per Lycoming SB 480F the max oil consumption formula for direct drive engines is: 0.006 x BHP x 4 ÷ 7.4 = Qt./Hr.
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So for a 180hp mooney running an average of 70% power (126hp) it should not burn more than .4 qts/hr.

I feel like low time engines burn about a quart every 8-10 hrs and once it was needing a quart every 3-4hrs I would seriously consider about tearing it down to find out what is wrong. That's basically dumping a quart in every fuel stop... thats a lot of oil.
 
Capt. Geoffrey Thorpe said:
Would be interesting to see the innards and find out how much wear there is (or isn't).

But if you are just sending it out...

Hope it goes as well as possible.
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Crank shaft had to be turned down to .006 on the mains and .003 on the conn rods. Probably only get one more overhaul out of it.
 
Salty said:
Crankshaft had to be turned down to .006 on the mains and .003 on the conn rods. Probably only get one more overhaul out of it.
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Did you have an oil filter on that engine? .006 undersize is a lot of crankshaft wear. May be from the camshaft debris.
 
No oil filter before, but I’m putting one on as part of the overhaul.

Unfortunately, the oil sample I took before the disassembly went missing. But the prior two showed nothing alarming.
 
dell30rb said:
So for a 180hp mooney running an average of 70% power (126hp) it should not burn more than .4 qts/hr.

I feel like low time engines burn about a quart every 8-10 hrs and once it was needing a quart every 3-4hrs I would seriously consider about tearing it down to find out what is wrong. That's basically dumping a quart in every fuel stop... thats a lot of oil.
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I think by BHP they expect you to use the nameplate HP, 180 in this case? Then as someone earlier calculated it would be 0.58 qt/hr which is a lot of oil!
 
idahoflier said:
Per Lycoming SB 480F the max oil consumption formula for direct drive engines is: 0.006 x BHP x 4 ÷ 7.4 = Qt./Hr.
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Back in the olden days, when I did emission work, I would get a batch of EGR valves - put them on my cars. Some would meet my NOx targets, some would be way off. Take them back to the valve guy - he checks them and declares that they are all "within spec.". Great. They don't effing work, but as long as they are in spec, then all is good.
 
Capt. Geoffrey Thorpe said:
Back in the olden days, when I did emission work, I would get a batch of EGR valves - put them on my cars. Some would meet my NOx targets, some would be way off. Take them back to the valve guy - he checks them and declares that they are all "within spec.". Great. They don't effing work, but as long as they are in spec, then all is good.
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OK? I'm not sure what you're trying to say? Earlier someone had posted a comment that I thought was saying Lycoming considers 1qt/hr as acceptable. I was just passing on the formula Lycoming provided for max oil consumption, which if this is a 180HP engine is 0.58 qt/hr and substantially lower...
 
Assembly went very well this weekend. Got the case together.
 
idahoflier said:
I think by BHP they expect you to use the nameplate HP, 180 in this case? Then as someone earlier calculated it would be 0.58 qt/hr which is a lot of oil!
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Incorrect, it's for the horsepower that you're producing.

Obviously you're not producing the same amount of horsepower the entire time you're flying, so generally you take a look at your cruise horsepower since that's where you spend most of your time. Basically more horsepower = more heat = clearances get bigger which is why lb/hp-hr are the units used.
 
Capt. Geoffrey Thorpe said:
Back in the olden days, when I did emission work, I would get a batch of EGR valves - put them on my cars. Some would meet my NOx targets, some would be way off. Take them back to the valve guy - he checks them and declares that they are all "within spec.". Great. They don't effing work, but as long as they are in spec, then all is good.
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Bad specs are always an issue. We ran into that places where some engineers didn't worry about a tight spec because they knew production "always" met [x] spec. That would usually work for initial production, but things would go south a few years later when the supplier moved the plant to another country and the quality changed. Then suddenly nothing worked, and you had nothing to go after them on because the spec technically allowed it. Then the engineers who made the original design had left the company so you couldn't ask them, either.
 
I'm still glad I'm doing this myself, but it is an insane amount of work. The paperwork alone has taken me well over 40 hours. I stopped tracking time spent a long time ago. But I have such a good understanding of the process, this model engine, the issues with this model engine, and this specific engine that I think the experience is invaluable.

The full AD, SB, SI, and SL list I had to process was over 500 documents. I only printed the ones that were applicable to my engine, and that is about 1.5" of paper.

We've approached this sort of like a practical checkride. Basically, I'm doing all the research and ordering of parts, bring it to my IA, and walk him through what needs to be done, why these are the right parts, how the work the third party guys did covers the AD's, show that it's all properly documented, and then he grills me and reads all the documents until he's satisfied we've got it all right. Saves him time (as opposed to him doing all the work directly), and forces me to educate myself fully. Even so, it's taken a lot of his time as well. This is all before we put a single part together.

The third party guys (Like Divco and AEA for example) don't really make it easy. They are obviously used to working mostly with bigger shops. Although, none of them have had issue with answering my many stupid questions.
 
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Salty said:
I'm still glad I'm doing this myself, but it is an insane amount of work. The paperwork alone has taken me well over 40 hours. I stopped tracking time spent a long time ago. But I have such a good understanding of the process, this model engine, the issues with this model engine, and this specific engine that I think the experience is invaluable.

The full AD, SB, SI, and SL list I had to process was over 500 documents. I only printed the ones that were applicable to my engine, and that is about 1.5" of paper.

We've approached this sort of like a practical checkride. Basically, I'm doing all the research and ordering of parts, bring it to my IA, and walk him through what needs to be done, why these are the right parts, how the work the third party guys did covers the AD's, show that it's all properly documented, and then he grills me and reads all the documents until he's satisfied we've got it all right. Saves him time (as opposed to him doing all the work directly), and forces me to educate myself fully. Even so, it's taken a lot of his time as well. This is all before we put a single part together.

The third party guys (Like Divco and AEA for example) don't really make it easy. They are obviously used to working mostly with bigger shops. Although, none of them have had issue with answering my many stupid questions.
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Why not simply order an engine rebuild kit from a reputable supplier? All used parts would have came to you with 8130-3 paper work, all new parts would have all SBs complied with at manufacture.
Just insist that all new parts come from the OEM manufacture.
 
Tom-D said:
Why not simply order an engine rebuild kit from a reputable supplier? All used parts would have came to you with 8130-3 paper work, all new parts would have all SBs complied with at manufacture.
Just insist that all new parts come from the OEM manufacture.
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I started to answer this, but it’s not worth it.
 
Seriously. The OP takes his engine out of his plane and completely rebuild's it and the thought process here is to attack him for being stupid for doing it one way vs another. I guess by this reasoning he should have just purchased a new engine from the manufacturer. Or even a new plane.

To each their own, personally I have enjoyed looking at the work knowing that my skill level does not come close to approaching what he has done.
 
Tom-D said:
Why? just realize what you have gone thru was futile?
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That’s not the act that was futile. It’s the act of explaining it to you that it is futile.
 
Salty said:
That’s not the act that was futile. It’s the act of explaining it to you that it is futile.
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To me, probably, but there are others that would like to know why you'd go to all that trouble when it's already done for ya
 
Tom-D said:
To me, probably, but there are others that would like to know why you'd go to all that trouble when it's already done for ya
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Nope. They already read the thread and aren’t trying to be jack donkeys. Your contributions to the thread so far is to tell me I broke rings that I didn’t break and three months after creating the thread give me advice on how I should have done it. Useless and bad advice, but the fact that you waited until now to impart it shows you aren’t attempting to be helpful, just a jack donkey.
 
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jallen0 said:
Seriously. The OP takes his engine out of his plane and completely rebuild's it and the thought process here is to attack him for being stupid for doing it one way vs another. I guess by this reasoning he should have just purchased a new engine from the manufacturer. Or even a new plane.

To each their own, personally I have enjoyed looking at the work knowing that my skill level does not come close to approaching what he has done.
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Oh ! no doubt he has done a wonderful job of overhauling his engine.

Now tell me how any overhauler would know if a SB has been complied with when they are getting new parts?

Using re-worked parts it is easy, the 8130-3 tag will tell you.

but new ?
 
Salty said:
Nope. They already read the thread and aren’t trying to be jack donkeys. Your contributions to the thread so far is to tell me I broke rings that I didn’t break and three months after creating the thread give me advice on how I should have done it. Useless and bad advice, but the fact that you waited until now to impart it shows you aren’t attempting to be helpful, just a jack donkey.
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Read what you wrote in post49, and who I was answering in post 80.
 
Ted DuPuis said:
Incorrect, it's for the horsepower that you're producing.

Obviously you're not producing the same amount of horsepower the entire time you're flying, so generally you take a look at your cruise horsepower since that's where you spend most of your time. Basically more horsepower = more heat = clearances get bigger which is why lb/hp-hr are the units used.
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Looking at the Lycoming manual, I see that you're correct, but wouldn't more heat make clearances get smaller and reduce oil consumption?
 
idahoflier said:
Looking at the Lycoming manual, I see that you're correct, but wouldn't more heat make clearances get smaller and reduce oil consumption?
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The engine is designed so that clearances get looser all around as the engine gets hotter. If you think about it, you wouldn't want the engine to get too hot and then seize up - that would be bad. So you have it backwards. I believe this is how all air-cooled engines are designed, although obscure oddballs out there might have them designed differently.
 
Ted DuPuis said:
The engine is designed so that clearances get looser all around as the engine gets hotter. If you think about it, you wouldn't want the engine to get too hot and then seize up - that would be bad. So you have it backwards. I believe this is how all air-cooled engines are designed, although obscure oddballs out there might have them designed differently.
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Mike Busch said the cylinder clearances are reduced (he was showing a pix of piston rings and commenting on the apparent looseness). Of course the heads are being cooled, so this may specific to pistons/heads.
 
Ted DuPuis said:
The engine is designed so that clearances get looser all around as the engine gets hotter. If you think about it, you wouldn't want the engine to get too hot and then seize up - that would be bad. So you have it backwards. I believe this is how all air-cooled engines are designed, although obscure oddballs out there might have them designed differently.
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OK, I was about to reply with a befuddled response, but I think I understand this now. Is it that as the cylinder expands, the outside of the sleeve gets larger and the bore also get's larger? Was thinking that the bore would get smaller due to expansion, but I can see due to the geometry this is probably unlikely...
 
Got the cylinders on. Making good progress.
 
On automotive engines some aluminum pistons are so much looser when cold that you can hear the piston skirts tapping the cylinder walls when they change direction (piston slap) at warm up. Piston to wall clearances tighten up when hot. Case in point- Chevrolet 5.3L v8 circa early 2000s.

On the other hand, some clearances open up- case in point is an aluminum oil pump housing with steel gears (ala Buick) where oil pressure drops when hot (not entirely viscosity related pressure drop).
 
Also have the rockers built out now but don’t have pics of that yet either.
 
Salty said:
Also got the engine mount painted, but I haven't got pictures of it yet.
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2018-03-31-22-39-22-jpg.61547
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that sht is sexy
 
Salty said:
I'm still glad I'm doing this myself, but it is an insane amount of work. The paperwork alone has taken me well over 40 hours.
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Excuse my ignorance on this subject, as I've yet to own a plane, but what's all the paper work that you have to do?

P.S. I just saw this thread now, holy moly was that a lot to read through.
 
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Matthew K said:
Excuse my ignorance on this subject, as I've yet to own a plane, but what's all the paper work that you have to do?

P.S. I just saw this thread now, holy molly was that a lot to read through.
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It’s about verifying you’ve done Everything that’s mandated by the faa, and recommended by the manufacturer, and documenting that you’ve done it. I need to be able to show the faa, and a future buyer that it was done correctly. And, I want to have the peace of mind knowing It was done correctly. This is stuff you don’t get if you farm it out to someone else. They probably do all the important stuff, but you rely on them to tell you what you don’t know.
 
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idahoflier said:
OK, I was about to reply with a befuddled response, but I think I understand this now. Is it that as the cylinder expands, the outside of the sleeve gets larger and the bore also get's larger? Was thinking that the bore would get smaller due to expansion, but I can see due to the geometry this is probably unlikely...
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That is correct. The cylinder bore expands outwards. In fact, to keep clearances, cylinders have a little "choke" at the top (slightly smaller bore at the top than the bottom) to account for the extra heat and thermal expansion that happens up there.

455 Bravo Uniform said:
On automotive engines some aluminum pistons are so much looser when cold that you can hear the piston skirts tapping the cylinder walls when they change direction (piston slap) at warm up. Piston to wall clearances tighten up when hot. Case in point- Chevrolet 5.3L v8 circa early 2000s.

On the other hand, some clearances open up- case in point is an aluminum oil pump housing with steel gears (ala Buick) where oil pressure drops when hot (not entirely viscosity related pressure drop).
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You can't compare a water-cooled automotive engine to our air-cooled aircraft engines in that regard, though. In an automotive application the block is effectively a constant dimensionally and with water cooling the temperature changes are much smaller than with air cooling. So you have heat created in the combustion chamber which is pretty efficiently removed from the engine. Our aircraft engines are much different in how the heat is dealt with as well as the rigidity of the structure.
 
Yeah Ted, wasn’t meaning to compare directly, just making the point that some expansion closes clearances while other expansion may open clearances. I don’t know jack about airplane engines, but have about 35 years of automotive engine experience. Some transfers over just fine, a lot probably does not (that’s why I caveat a lot of my input with “ I ain’t an A&P).
 
455 Bravo Uniform said:
Yeah Ted, wasn’t meaning to compare directly, just making the point that some expansion closes clearances while other expansion may open clearances. I don’t know jack about airplane engines, but have about 35 years of automotive engine experience. Some transfers over just fine, a lot probably does not (that’s why I caveat a lot of my input with “ I ain’t an A&P).
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Lots of A&Ps don't know much about those sorts of details of aircraft engines, either. :)

You are correct much of it trasnfers over, but there are some significant difference.
 
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