crosshatch patterns looks ok, so doesn't look like they're glazed. There's also light scoring, nothing to worry about according to the picture.
Some oil residue on the bottom of the cylinder, yes and no. If let to cool down and not ruin that borescope, that looks ok to me.
Now looking at that outside vid of your taxi in (and also the onboard cam) it looks more like the engine is not running regularly, but cuts-out shortly, which explains the puffs of black and blue smoke.
First I would do is confirm with the data off your Dynon (EGT, FF drop, FP fluctuations), and then to properly adjust the mixture settings, and whilst at it clean the fuel filters.
Downloaded Dynon files yesterday. I'm thinking of using Savvy unless there is another software recommended to be better. This will be my first time using data to diagnose. I'll be learning more about and how to use/read this info this week.
I'm just learning here.
1. Why did you replace the cylinders? Was it just because of the smoke color? Was there a problem with making power/compressions?
2. Why a mixed weight oil for break in? I recall using straight mineral oil per the book.
3. Are the cameras the problem? Do you have too much data that otherwise would be fine if you did not know?
1. Cylinders glazed at 173 hrs. Still don't know why. Blue smoke is indication that oil is passing the rings. It was that and higher than normal oil usage. Power and compression were still good. A/P AI and engine builder confirmed scope of cylinders for glazing. The only way to solve that is to remove, deglaze (hone) the barrel and re-ring. That is what I did.
2. First time around I did use straight mineral oil. Still glazed. This time around I'm trying XC because suggested by many that it is also good choice for break-in oil.
3. I wouldn't think the cameras have any bearing on the engine issue. I did notice my oil usage was higher than normal but that, coincidentally, was at the day that my hangar neighbor mentioned it to me as I taxied past. I didn't know color it until it was brought to my attention. Then I filmed it.
Sounds and looks like a sticky valve at the stumble when he says, "blue".
Rich condition would be black.
This is my my experience from other planes.
How do all the plugs look?
I cleaned, gaped and tested all plugs 10 hours when the cylinders where reinstalled. I removed and inspected after this taxi in. I pulled the plugs again and yes a couple where wet so I thinking I'm still rich. I cleaned, checked gap again and retested all plugs. I did find one bad plug. That may/may not be the issue of the hesitation seen in the video. Pic of plugs after removal attached at the bottom.
Good walls and bad guide/s? Wobble check?
We checked when we cleaned and reinstalled all the valves. Nothing evident that there was an issue. Not to say it hasn't become one. I do have the wobble test on my to do check off list.
Nobody else said it, but I will. Beautiful landing with absolutely NO shimmy on the roll out. Impressive.
Thanks. It is one of my better ones. It was a good day to record video!
Sorry, misread as 1/4 qt for each of two 1 hr flights. 2 qts consumed during 10 hr break in is pretty normal.
No problem. I thought that might be the case.
Looks like just trace areas of glazing at top on one pic. Some pics are hard to tell what I am seeing, so can't say. Pooled oil is not too bad. I wouldn't worry about it until 20 hours. Keep the power above 65% for another 10 hours. Good chance the walls may wear in a bit more and oil consumption will drop during that time.
That's my plan as of right now. Keep flying high power for another 10-15 and watch.
I don't see enough oil in the cylinders to be creating blue smoke from that source, especially only at idle; it would be constant and likely not visible. I speculate that it is either a rocker box drainage issue or it is black/grey and from an excessively rich idle mixture. When the engine is cold, it wants a richer mixture, so not bad. Once hot, it wants a leaner mixture, so starts creating smoke.
On the assumption it is blue, Mostly think the rocker box is filling up with more oil than normal (moderate blockage) and as soon as you pull back to idle (strong vacuum) on roll out it is pulling that oil in passed the valve guides and burns. Used to see this all the time in the old days with cars when the valve seals wore out, though a different issue as heads were not horizontal.
Very possible a piece of trash got jammed in the 45* AN fitting on the cyl head while in the shop. Flows some, so no issue at higher MAPs.
I had read about this from your previous posts here on VAF. Because of that, I cleaned the cylinder ports, return drains, hoses and made sure the return passage at the case was also clear. I'll check again to be sure it has not blocked up since then. As a side note, I have also followed your MP method to set up the mixture. That went well before I had these cylinders R&R. I'll go through that process again.[/QUOTE]
