Definitely looking red here...
Preflight - above and beyond
- Thread starter TMetzinger
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Depends which engine. On an 1820 it's a little over 2 oz comes out. In order to get 2 oz into the combustion chamber though, you need to flood about 3 quarts into the rocker box, because that's how the oil gets in there. It has to flood the rocker box and go up through the valve guide, and then the valve has to be open to let it in the combustion chamber.
Preflight over & above-
This is hard to describe, but...just what's different from the last time I flew the plane....or anything that looks different for this type of plane
I just came back from flying & I noticed...
The trim on the C-150 wing strut was cracked
The hinge rod on the trim tab was fixed (pushed in)
The knob fell off the cigarette lighter (screwed it back on)
Dents? wrinkles? Something at an odd angle?
As people fly & gain experience, they notice things even though they aren't listed in the pre-flight check list.
This is hard to describe, but...just what's different from the last time I flew the plane....or anything that looks different for this type of plane
I just came back from flying & I noticed...
The trim on the C-150 wing strut was cracked
The hinge rod on the trim tab was fixed (pushed in)
The knob fell off the cigarette lighter (screwed it back on)
Dents? wrinkles? Something at an odd angle?
As people fly & gain experience, they notice things even though they aren't listed in the pre-flight check list.
TMetzinger
Final Approach
OK, I did.
What I think it means is that while we don't EXPECT hydraulic lock, we pull the prop through to ensure the scavenge pump did the job, and therefore we PREVENT hydraulic lock.
Is that correct? I want to be sure I'm understanding this.
Nah, they don't really need oil until they warm up. Main thing oil does in an engine is remove heat.
Correct, but we aren't preventing hydraulic lock, we are preventing in flight catastrophic failure of the engine. We use the hydraulic lock as an indicator symptom, kinda like bumps with measles. We see the bumps, so we know we have a problem, but the bump isn't what's going to kill you, it's brain fever that's going to kill you, both are caused by the measles virus.
Richard
Final Approach
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Ack...city life
Radials & Medical Advice mixed with a bit of front porch squabble ...POA is awesome!
TMetzinger
Final Approach
Ah... So we're CHECKING for hydraulic lock, as a SYMPTOM of a failed scavenger pump, to PREVENT inflight destruction of the engine.
Thanks - wish it hadn't taken so many posts to get to this point, though it was mildly entertaining.
fgcason
En-Route
But it's so much better than the routine shallow answers you normally get nowadays. You actually learn something useful rather than studying for the test answer that is seldom overly useful in the real world.
I love it when Tom starts the make you think before getting the full answer routine.
Tom-D
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Tom-D
You got it.. IF we have a failure of the oil pump, we may have a oil in the lower cylinders. That oil will damage the engine upon start.
The OWT says it is the oil drain down that causes this to happen, IF this was true, we would have a hydraulic lock every time we shut down the engine.
Tom-D
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Tom-D
Managing the conversation,,,,, is what instructors do.
and OBTW,,, Henney pulls the radial he flys thru 12 blades because he has a geared engine, and it takes 12 blades to rotate the crank shaft 2 revolutions.
Next question, How do the operators of the Mars, C118, and the super connie make sure the engine has no hydraulic lock.
On my preflights, I finish by stepping out about 25' or so, and walking around looking "big-picture" one more time... just in case I missed a forest while I was looking at the trees (so to speak). Have never caught an airframe issue this way, but managed to find a quart of oil I left on the wing, in front of the door.
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And Tom, I rather enjoy your Socratic teaching... learning through reasoned thought. Different ways for different folks, but I think it's good fun, and the message sinks in better, too.
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And Tom, I rather enjoy your Socratic teaching... learning through reasoned thought. Different ways for different folks, but I think it's good fun, and the message sinks in better, too.
Tom-D
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Tom-D
Nope we never touched the engine other than to check oil on preflight.
Tom-D
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Tom-D
Just crank it 12 blades with the mags off, and hope the srarter clutch didn't fail.
IF it did, and the engine had a hydraulioc lock, we would have a chips light before we got the run up completed.
WE removed the starter every phase and checked the lock out feature. a real PITA
IF it did, and the engine had a hydraulioc lock, we would have a chips light before we got the run up completed.
WE removed the starter every phase and checked the lock out feature. a real PITA
flyingcheesehead
Taxi to Parking
Breather tube.
Never seen it in an aircraft POH, but we had one freeze over a couple winters ago, blow an oil seal, and luckily there were still two quarts left when the pilot landed at the nearest airport.
Tom, thanks for the info. Very educational.
Never seen it in an aircraft POH, but we had one freeze over a couple winters ago, blow an oil seal, and luckily there were still two quarts left when the pilot landed at the nearest airport.
Tom, thanks for the info. Very educational.