Why change oil in airplanes?

Camguard is supposed to be added at 5% for normal ops. That's one pint per 10 quarts. Perfect for my Cessna. In my 320 I used a little over half a pint in 6 quarts.
 
TazzyTazzy said:
This sounds good for oil changes. What about when you topping up? Every 6 quarts, then add one of these?
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That would work as well, the easiest way is to dump about an ounce and a half of oil out of each of your top up quarts into an empty and re top with an ounce and a half of Cam Gaurd and use those between oil changes.
 
Unit74 said:
Err......not really. You need to change it because of the contamination not because the oil degrades. If we had 2micron filtering, it would last a very long time. If you could filter out all the contaminants, keeping it topped up would be all you need.
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If we had 2 micron filtering, the acids would still circulate through the engine.

Dan
 
stratobee said:
Another hidden cost in the piston vs turbine debate. If you're like me, better at doing my job than pretending to be a mechanic, then I go to the shop to have it done. With the Aerostar that's a 3hr deal minimum with decowling etc. It ends up being $350-500 each time with oil filters, oil and labour.

If you do that every 25hrs as they recommend for turbo engines, on a 1800hr TBO, you're looking at $36K in oil changes over the life span of the engine! If you do it every 50hrs, it's still a considerable $18K. That's the same cost as your average hot section inspection, I would venture. Turbines go 800hrs between oil changes.
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Do yourself a favor.....

Do a little research...and find out how often Pratt and Whitney recommends that you perform a compressor and compressor turbine wash for a PT6.;)

I will be waiting for the :eek::eek::eek::eek::yikes::yikes: response.
 
TEFLONSEAN said:
Do yourself a favor.....

Do a little research...and find out how often Pratt and Whitney recommends that you perform a compressor and compressor turbine wash for a PT6.;)

I will be waiting for the :eek::eek::eek::eek::yikes::yikes: response.
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Thank god I bought a Garrett. None recommended. :thumbsup:
 
we never changed oil in the T-56, in either the P-3 or the C-130. ran 3 micron filters and went until it was pulled from the wing. Never saw a bearing failure it was always low power, turnbine failure or a compressor FOD.
Never changed oil on the R/R Dart. sent in the oil sample to Chrysler leasing every Friday. and they would send us a new rental when they saw the need. The whole fleet of A6s never changed oil either, just kept topping it off, If it took more that 12oz after 40 hours they pulled the J52-P408.
 
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I was told by the former owner of my plane not to worry about changing the oil. His view was the engines burn 1-2 gph from a tank of 26 gal so why bother changing the oil. Just dump another 5 gallons after your $1000 hamburger run.

Since I've owned it I've now rebuilt both engines, and I'll buy a barrel of oil and change the oil every 25 hrs. The rebuilt engines only use .5-1gph so they run great.

Fi the engines are p&w r1830-92 installed in a low time dc-3


Sent from my iPad using Tapatalk HD
 
Nah, should be fine. I come from Commanders, I know where to look for cost effective maintenance. If you go to Naples Jet Center or Eagle Creek with your Commander, they'll be $1000+/hr planes. But when you go to the old guys in a hangar in NorCal, then it's a lot less. Guys who repair stuff rather than just replace with new. My hourly cost will probably increase about $100-200 compared to Aerostar. :crazy:
 
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stratobee said:
Nah, should be fine. I come from Commanders, I know where to look for cost effective maintenance. If you go to Naples Jet Center or Eagle Creek with your Commander, they'll be $1000+/hr planes. But when you go to the old guys in a hangar in NorCal, then it's a lot less. Guys who repair stuff rather than just replace with new. My hourly cost will probably increase about $100-200 compared to Aerostar. :crazy:
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I will bet your hourly cost on the turbine commander will be $1200hr or greater.
 
Henning said:
I will bet your hourly cost on the turbine commander will be $1200hr or greater.
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Not even the last Dash 10 models (the 695's) will cost that much if sensibly maintained. A 690B is maybe a $1000/hr plane with the Dash 10's. With the Dash 5's it's less.
 
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RotorAndWing said:
How do you figure it's less between the -5 and -10 other than fuel flow?
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Dash 5's are pretty easy to get by with good times these days (because everyone is or has done the 10 conversion). You can just hang a midtime engine for about $20-30/hr left on them instead of doing HSI. Dash 10's not so much as they're in demand.

And part 91 you don't need to O/H as long as you do all inspections and abide by cycles.

So you're spending $800hr on the Aerostar?
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No, about half (although it's impossible to put a number on it as I'm selling with new engines and can't reap the benefits of the TBO). The turbine should be $550-650/hr because I don't have any of the recurring items. And Dash 1's are also priced lower. But this is not my conjecture. Figures are based on operating costs from other Commander part 91 owners.
 
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stratobee said:
Dash 5's are pretty easy to get by with good times these days (because everyone is or has done the 10 conversion). You can just hang a midtime engine for about $20-30/hr left on them instead of doing HSI. Dash 10's not so much as they're in demand.

And part 91 you don't need to O/H as long as you do all inspections and abide by cycles.



No, about half (although it's impossible to put a number on it as I'm selling with new engines and can't reap the benefits of the TBO). The turbine should be $550-650/hr because I don't have any of the recurring items. And Dash 1's are also priced lower. But this is not my conjecture. Figures are based on operating costs from other Commander part 91 owners.
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I'd be interested to see you operate it at the same price as a 421.
 
stratobee said:
Dash 5's are pretty easy to get by with good times these days (because everyone is or has done the 10 conversion). You can just hang a midtime engine for about $20-30/hr left on them instead of doing HSI. Dash 10's not so much as they're in demand.

And part 91 you don't need to O/H as long as you do all inspections and abide by cycles.


No, about half (although it's impossible to put a number on it as I'm selling with new engines and can't reap the benefits of the TBO). The turbine should be $550-650/hr because I don't have any of the recurring items. And Dash 1's are also priced lower. But this is not my conjecture. Figures are based on operating costs from other Commander part 91 owners.
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Someone has sold you a bunch of bunk on owning and operating one of these. But never the less, good luck with it. I've seen one too many go down the same path you are heading only to wind up dumping the plane to get out from under it.
 
RotorAndWing said:
Someone has sold you a bunch of bunk on owning and operating one of these. But never the less, good luck with it. I've seen one too many go down the same path you are heading only to wind up dumping the plane to get out from under it.
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Kinda makes me flash back on the Merlins people got sold the same way. They never worked out either at the described budgets.
 
Henning said:
I'd be interested to see you operate it at the same price as a 421.
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Less than. 421s are generally considered $700/hr planes.

$650/hr for a 690? :rofl: not even close.
 
There's ownership and then there's ownership. It makes no sense to overhaul engines on older aircraft of these types, because that would cost 4x more than they're worth. You have to be prepared to be its last owner. That's where the calculations and examples always go wrong, because we're comparing them to aircraft that will have an afterlife and a resale value. You can make turbines as expensive or as cheap as you want to depending on your tolerance level for:

1. Running over TBO.
2. Oddball types.
3. Willingness to be its last owner.

If I fly my plane for the 1100hrs that are left on the engines and then just walk away from it, even with a $50K per side estimated HSI inspection halfway down the road, and with an 'expensive' $20K phase inspection each year (phase = annual) this plane will cost $300/hr as it stands today without fuel. That's $500/hr with fuel.

If I continue to fly it after TBO, then the price per hr goes down. If I on top of that decide to sell it for scrap or part it out at the end, then the price goes down even further.

There are ways to skin a cat.
 
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stratobee said:
There's ownership and then there's ownership. It makes no sense to overhaul engines on older aircraft of these types, because that would cost 4x more than they're worth. You have to be prepared to be its last owner. That's where the calculations and examples always go wrong, because we're comparing them to aircraft that will have an afterlife and a resale value. You can make turbines as expensive or as cheap as you want to depending on your tolerance level for:

1. Running over TBO.
2. Oddball types.
3. Willingness to be its last owner.

If I fly my plane for the 1100hrs that are left on the engines and then just walk away from it, even with a $50K per side estimated HSI inspection halfway down the road, and with an 'expensive' $20K phase inspection each year (phase = annual) this plane will cost $300/hr as it stands today without fuel. That's $500/hr with fuel.

If I continue to fly it after TBO, then the price per hr goes down. If I on top of that decide to sell it for scrap or part it out at the end, then the price goes down even further.

There are ways to skin a cat.
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Yep, understood, and in 30 years around airplanes and some of the slickest, most knowledgeable owners out there with life long industry connections, I have seen none of them that could operate a turbine twin anywhere close to the budget you are deluding yourself into believing because you want a turbine plane. That's fine all in all, just be prepared to spend twice what you are thinking you can get away with quoting numbers that present themselves as the most perfect possible circumstances.
 
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stratobee said:
There are ways to skin a cat.
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The cat is safe here, it's the naive owner that is at risk of being skinned. :rolleyes:

BTW, have you priced what a FCU would cost? Starter Generator? How about a pressurization controller? Windshield?

Does your airplane have a NiCad battery? Have you priced one of those lately?
 
Henning said:
Yep, understood, and in 30 years around airplanes and some of the slickest, most knowledgeable owners out there with life long industry connections, I have seen none of them that could operate a turbine twin anywhere close to the budget you are deluding yourself into believing because you want a turbine plane. That's fine all in all, just be prepared to spend twice what you are thinking you can get away with quoting numbers that present themselves as the most perfect possible circumstances.
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Go and check at the Beech Forum and see what some of the guys run the old King Air's for with runouts. Especially look for posts by Dave Siciliano. These are aircraft with calendar items I might add, which my plane doesn't have. He averages $40K per year on 150hrs on his C90B and that's when the gear overhauls are $30K a pop.

RotorAndWing said:
The cat is safe here, it's the naive owner that is at risk of being skinned. :rolleyes:

BTW, have you priced what a FCU would cost? Starter Generator? How about a pressurization controller? Windshield?

Does your airplane have a NiCad battery? Have you priced one of those lately?
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FCU's are expensive, for sure. Batteries are expensive ($2800/pop). Starter generators was just overhauled for $1500. Windscreen left side used I just got for $1100.. Really, it's not dipped in gold. Take away the turbines and the systems are just the same and cost as much as any piston twin from the same era...
 
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Every long time operator of twin turbins of that caliber I know budgets $1200 hr for operations and feels good about coming in at $1000. YMMV.
 
Henning said:
Every long time operator of twin turbins of that caliber I know budgets $1200 hr for operations and feels good about coming in at $1000. YMMV.
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Don't burst his bubble. He might as well go full jet next. There is a Westwind on TAP for $315k that is right up his alley!
 
Henning said:
Every long time operator of twin turbins of that caliber I know budgets $1200 hr for operations and feels good about coming in at $1000. YMMV.
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I think for a 690 that's a sensible and correct sum.
 
stratobee said:
I think for a 690 that's a sensible and correct sum.
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It's mostly attributable to a level of horsepower rather than model. The difference between models of a certain HP is pretty much luck of the draw and how you operate. The threshold of operations for entry into the turbine twin market is $1000hr, it starts there and goes up. You may get lucky and God will shine on you for doing good deeds and you will manage to come in at $800hr on years you've been really good, but to get those kind of numbers, you need to be sponsoring water wells in places like Haiti and Africa, because those numbers require exquisite karma, walking with Christ level karma.:lol:
 
I'm having trouble finding any Turbo Commanders with... Century engines?
 
Cpt_Kirk said:
I'm having trouble finding any Turbo Commanders with... Century engines?
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The "Century" engine is a TPE-331 that is either the -1 or -2. These are old engines that were primarily used in the '60's. Garrett made several improvements after these which are essentially the engines used today.

The old Century series are getting harder to find components for, hence why operators have moved away from them. Basically the same with a PT6-6 or -20, they are out there but not well supported.

The Twin Commanders in question are the old 680W, 680V and 680T, which are essentially 680FLP's that had the Garrett's hung on them. The line didn't see any improvements until the 690's came along with improved engines and considerably beefed up airframe.
 
So, a serious question: where do you even find one of these to buy? I only find one Turbo Commander on the market right now that isn't a 690 or newer, and it's a 681. Compare that to Lear 23s or Westwinds where I can find no shortage.
 
Ted DuPuis said:
So, a serious question: where do you even find one of these to buy? I only find one Turbo Commander on the market right now that isn't a 690 or newer, and it's a 681. Compare that to Lear 23s or Westwinds where I can find no shortage.
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Honestly I thought all of these (680 turbo props) were already scraped out.
 
RotorAndWing said:
Honestly I thought all of these (680 turbo props) were already scraped out.
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That was my thought, too. The only one I've seen got sold to the local A&P school. It flew in (barely) and then the A&P instructor hot started the hell out of both engines, resulting in massive fire out the tailpipes.
 
RotorAndWing said:
The "Century" engine is a TPE-331 that is either the -1 or -2. These are old engines that were primarily used in the '60's. Garrett made several improvements after these which are essentially the engines used today.

The old Century series are getting harder to find components for, hence why operators have moved away from them. Basically the same with a PT6-6 or -20, they are out there but not well supported.

The Twin Commanders in question are the old 680W, 680V and 680T, which are essentially 680FLP's that had the Garrett's hung on them. The line didn't see any improvements until the 690's came along with improved engines and considerably beefed up airframe.
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Thanks.
 
I allow myself to look at airplane porn once per week dreaming of Conquests, Cheyennes, Commanders, and King Airs etc. I really need you guys to quit bringing reality into these threads.
 
James_Dean said:
I allow myself to look at airplane porn once per week dreaming of Conquests, Cheyennes, Commanders, and King Airs etc. I really need you guys to quit bringing reality into these threads.
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Just wait until we go for a ride in a 690. ;)
 
Just spent the first part of this week with the CEO of the company I work with who has a Cheyenne IIIA. Just spent the better part of $1mm redoing the engines. Gulp.....
 
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