She's been a sitter, probably needs a Top Overhaul??

Normally you'd think there would be 8 cam lobes to operate a 4 cylinder opposed engine, except that two of the cam lobes on a 4 cyl Lycoming cam are used to operate two valves each on opposite sides of the engine. The cam turns CW when viewed from the rear. Usually it will be one of these lobes that will be the first to have scoring or corrosion problems. If you only want to check one cylinder, this suggests that you might remove the number 2 or number 3 cylinder to see the condition of a most heavily used cam and lifter set. The most likely scored cylinder will be on the left side of the engine and that would give you a chance to check for that also. Your mechanic may have a favorite one to check too.
 
Tom-D said:
Why not get an A&P mentor who will supervise what you do?
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Some folks just don't know what they don't know.

Owner assist is the way to go for sure.
 
The year of the cam is probably a better determiner if it will go south. There is a trend that Lycoming cams from the 1990s to some of the 2000s have bad metallurgy. Also if you are running it with sticky valves then that is a cam killer. So $1000 for new cylinders /$500 to rebuild. If they are on a mooney IO-360 High Horsepower they are $2000 new.
 
overdrive148 said:
She's a Sitter Queen!
Doesn't run on kerosene
Cylinders are all unclean
Guaranteed to blow your dime!
Anytime!
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now that was some poetic justice!
I think that I will find a sitter queen as a project plane at a major discount to fix up once I have my A&P.
 
I went through this exercise and came to the realization that with my super busy schedule at work and school coming up soon that I'd be better offer buying a nicer more expensive plane that already has what I need without spending time and money in a shop.
 
Dan Thomas said:
Short flights will do it, too.
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Whats short flight ? How long the flight has to be to keep engine happy ?
When I am not flying for my job I always do once a week half hour hops to keep me happy and I am sure I am keeping engine happy too since my peak oil temp occurs about 10 minutes after the take off to burn up all the moisture. When I level off at 3-4 K AGL it starts decreasing especially during winter times. So whats the purpose of fooling around for another half hour .
 
blueskyMD said:
Whats short flight ? How long the flight has to be to keep engine happy ?
When I am not flying for my job I always do once a week half hour hops to keep me happy and I am sure I am keeping engine happy too since my peak oil temp occurs about 10 minutes after the take off to burn up all the moisture. When I level off at 3-4 K AGL it starts decreasing especially during winter times. So whats the purpose of fooling around for another half hour .
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You may get the oil hot, but how long does it require to purge the water out of the crankcase?
 
I've always been told a least an hour at flying temp. Might as well fly it...:goofy:
 
Twin_Flyer said:
I was talking flying it not running it... Wow...:mad2:
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The point still stands, you're running the engine while you're flying it. Water is going as it gets run.

But, as Tom alluded to, there is a way to remove the water but not by running the engine to drive it out.
 
mondtster said:
The point still stands, you're running the engine while you're flying it. Water is going as it gets run.

But, as Tom alluded to, there is a way to remove the water but not by running the engine to drive it out.
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Actually an oil drain and flush will get it out as far as possible. specially after you run it and get the oil mixed with the oil.
Otherwise the water will sink below the oil and air drying won't get it out either.
When I preserve an engine for long term storage, I run the engine on prez oil, get it hot as possible with out harming it, drain the oil. place it in a dry container and seal it with desiccant.

On the aircraft, I do the same but no container, but place dryer plugs in the top spark plug holes then plug the exhaust and carb.
 
Tom-D said:
Actually an oil drain and flush will get it out as far as possible. specially after you run it and get the oil mixed with the oil.
Otherwise the water will sink below the oil and air drying won't get it out either.
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Yep, I've drained the oil in some engines and a stream of water will come out before the oil starts. Some engine types seem worse for this than others.

You probably figured out that my earlier response was thinking of solely trying to get the water out by running it, which will never happen. But draining the oil will get it out, or at least get as much out as you're probably going to get out.
 
mondtster said:
Yep, I've drained the oil in some engines and a stream of water will come out before the oil starts. Some engine types seem worse for this than others.

You probably figured out that my earlier response was thinking of solely trying to get the water out by running it, which will never happen. But draining the oil will get it out, or at least get as much out as you're probably going to get out.
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Diesel fuel accepts water very well flush the sump with it and you'll really be surprised what you get out, specially when you run the engine at idle for about a minute. the sludge that normally doesn't come out gets deluted and drains too.
 
Top overhaul? Budget $6k - $10k. But, the good news: I've personally seen airplanes that were stored outside in humid environments, with flat tires, and mildew growing all over them fly again with only a weekend's worth of scrubbing and inspections. (A 250hp Commanche nontheless). My personal airplane (172H) sat unused in Southern California for a period of 9 years once, and after a battery and fresh gas it flew away, never missing an annual again or needing any major engine work in almost 25 years. I'm getting ready to turn the keys on another next week that has sat in a moist canvas shelter for the last 3 years, and I don't expect any major hiccups.

Yes, the guy that gets bitten by major expenses spreads the word and grumbles about it a lot. But there are plenty of guys that do a careful inspection and fly away. But that's not interesting news...

YMMV!
 
Heck, look at it carefully, but nearly every airplane in the US fleet has been a "Sitter" at some point in it's life, for some reason. If the engine can be got running safely, and runs fine, just go fly it and check it out; chances are you won't need to do anything major, but in my experience (1940's planes I own) if you do, it probably won't be the engine proper; I'd look out for accessories like the mags or generator screwing up before anything happens with the other parts. If get it and you like the plane, fly it a bunch, that's the best thing you could do for it!
 
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