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Lycoming's Turn

Hmmm??? Normally one would expect to be able to use a cylinder for longer than one overhaul period. Yet there is no mention that Lycoming would issue a trade in credit when these cylinders need to be removed. Shame on Lycoming.
 
Reading the dates it is about the same as those wrist pin bushings. So on top of your lousy wrist pin bushings, you have POS cylinders. Nice job Lycoming, you should be proud for producing multiply defective engines.
 
I think it’s ironic how guys criticized the SAP and ECI cylider ADs that turned them into one run wonders claimed that proved Lycoming was the best. Even the hot-rod cylinder shops said that. I’ve experienced the one-run problem with ECI and SAP cylinders. Welcome to the club. ;)

But heck, I suffered through a Continental crankshaft issue 20 years ago, missed the Lycoming one that happened after, and now I get to pull my Superior engine for a crankshaft issue. No one’s immune to manufacturing defects. I think the only thing that’s really changed through the years is liability concerns, and that’s probably fueled by internet communication. Everyone knows about every little failure these days.
 
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Maybe someday they will come out with a honest limit for the CHT's. Abnormally high says nothing! But a long history of exhaust valve issues, wobble test SB, and wet head cylinders kind of points to the 500 degree CHT limit being a large pile of crap.
DENNY
 
The AD issue date was October 11, 2018. I'm surprised it took so long to show up in our forum.
 
Maybe someday they will come out with a honest limit for the CHT's. Abnormally high says nothing! But a long history of exhaust valve issues, wobble test SB, and wet head cylinders kind of points to the 500 degree CHT limit being a large pile of crap.
DENNY
I use 400 degrees CHT as my personal limit. If it goes over this on a hot day I richen the mixture by an appropriate amount.
 
I try to keep mine in the 330-340 range. #2 will go up on a hard climb, I usually pull back above 380. Taking the time to get baffling, carb, and ramps right pays off.
DENNY
 
Our Huskies always ran cylinders much hotter than I would have liked. While we're talking engines... I just bought an L-19 that runs like a fine Swiss watch. O-470-11. What I discovered is that it is very, very difficult to pull the prop through. Really, really stiff. Like you could do pull ups on it. Anyone run into this? Last time I did, I passed on a purchase of a Pacer, but this one got past me. Don't ask me how. It just did. Bearing? 1,100 SMOH, 100 hrs on cylinders. Uses no oil, Oil pressure great, nothing obvious in the oil filter. Help please!
 
7:1 compression shouldn't cause much trouble with pulling it through but all my experience the 470s used 88" props so lots if leverage. How does the starter spin it? Maybe a starter clutch problem?
 
I thought about the starter. Haven’t had a Chance to pull the plugs. We’re going to start with a stethoscope
 
Mine were always stiff when hot, and loose when cold. Ran one -11 to tbo and 8 -15's to tbo with no related problems. I would suggest if your screen remains (mostly) metal - free, to keep running. That said, I never had one so stiff that anywhere near pull-ups were possible so if you really mean that.. could be a problem. I'd also take a peek to see if your cylinder walls are scored. Of the two cylinders changed in all those runs, one was due to scuffing and the other was due to (unrelated to your issue) premature exhaust valve guide wear. (by the way the first sign of this is a bunch of carbon in your screen). I do remember being concerned with the engines being hard to turn when hot but never saw a definable problem. I did the teardown and assy. for overhaul on all of the -15 engines and the bearings always looked good after 1500+ hrs. The factory 520 (knocked in the head to be a Pponk) engines (3 so far) also are stiff to turn when hot. Not sure if this helps but that's been my experience.
 
I thought about the starter. Haven’t had a Chance to pull the plugs. We’re going to start with a stethoscope

start with the oil screen/filter inspection..... then pull plugs....

oil transfer collar tight? to tight can cause crank to heat & crack.... too loose and prop won't behave....
 
start with the oil screen/filter inspection..... then pull plugs....

oil transfer collar tight? to tight can cause crank to heat & crack.... too loose and prop won't behave....

The -11 is fixed pitched with no transfer collar. -15's were constant speed with collar and fitting for rear-mounted governor.
 
Thinking about all of the above. I reckon if I'm lucky it's a piston too big for its britches etc. A cylinder replacement would be easy. The plane is in the UK so I'll try to go there and start all this myself next week. Thanks for the responses. Had a mechanic check the screen said it looked normal enough. I once had an L-19 spin a bearing and the pilot made a perfect 3 point forced landing - 50 feet up. I'm getting old and wanna be older. Thanks folks.
 
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