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Oil in cylinders

chrisi456

Member
Is it ever normal to have oil sitting in a cylinder discovered with a bore scope? I have excessive oil usage and borescoped my Titan IO 370 and discovered oil sitting in the bottom of two cylinders.

Thanks
 
Is it ever normal to have oil sitting in a cylinder discovered with a bore scope? I have excessive oil usage and borescoped my Titan IO 370 and discovered oil sitting in the bottom of two cylinders.

Thanks

No, that is not normal. It points to an issue with the ring/wall interface and is typical with high oil consumption due to ring/wall issues. Is this a new engine / overhaul. Pooled oil/high consumption is typical with glazed cylinders. (they show as a brown or tan, translucent coloring of the cyl walls instead of shiny steel). Can you see a defined cross hatch pattern on the walls? If you have enough cylinder wear and the cross hatch disappears, you will have pooled oil. Various other cyl and ring issues can cause this.

Excess valve guide wear can cause oil burning, but it would seem unlikely to dump enough oil to see pooling in a lycoming (due to low oil flow to rockers). Exhaust valve stems just above the head would be full of black crud (oxidized oil) in this case. This area is visible through exh port.

Larry
 
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Is it ever normal to have oil sitting in a cylinder discovered with a bore scope? I have excessive oil usage and borescoped my Titan IO 370 and discovered oil sitting in the bottom of two cylinders.

Thanks

How much oil was in the cylinder? How much time between when it ran and when you scoped it?

How many hours per quart?

Some sort of quantification is needed to know if it is normal.
 
I would post a picture but have been unable to in the past. Titan 370 with 230 hours on the engine. 5 hours per court of oil led me to borescope, it never changed from day 1. I saw oil pooling in two cylinders. That led me to have the engine honed and new rings put on. 20 plus hours into the new break in, the oil consumption went from 1 quart per 2 hours to improving to about 1 quart in 4 hours, now getting worse, 1 quart per 1.5 hours. They are Ni cad cylinders. I followed the new break in procedures. I used Phillips 20W-50 based on Titan's recommendation for the first break in and pure mineral oil on the second break in based on the engine mechanics recommendation. My engine temps are much improved on the second break in and it seems to be running well. I e-mailed Lycoming and they said Ni cad cylinders can take up to 50 hours to break in, I'm just getting discouraged since they appeared to improve and are now getting worse after 20 plus hours.
 
I would post a picture but have been unable to in the past. Titan 370 with 230 hours on the engine. 5 hours per court of oil led me to borescope, it never changed from day 1. I saw oil pooling in two cylinders. That led me to have the engine honed and new rings put on. 20 plus hours into the new break in, the oil consumption went from 1 quart per 2 hours to improving to about 1 quart in 4 hours, now getting worse, 1 quart per 1.5 hours. They are Ni cad cylinders. I followed the new break in procedures. I used Phillips 20W-50 based on Titan's recommendation for the first break in and pure mineral oil on the second break in based on the engine mechanics recommendation. My engine temps are much improved on the second break in and it seems to be running well. I e-mailed Lycoming and they said Ni cad cylinders can take up to 50 hours to break in, I'm just getting discouraged since they appeared to improve and are now getting worse after 20 plus hours.


there is problem going on in that engine. i have never had a set of cyls use that much oil during break in even back in the day when we were all running chrome cys.

how was the engine operated during the first five hours on both break-ins? is sounds like either a glazed cyl problem, wrong type rings, or bad cyls. half to 3/4 a quart an hour is way to much for a 20hr engine. im breaking in a 320 right now that has run 7hrs and is still less than 1/2 qt down.

bob burns
RV-4 N82RB
 
I ran the engine the way my Mech said to do it, hard, not hot. Full power on takeoff, stay low altitude for most power, change MP every 15 min or so. First flights were between 70 and 82% power. I have 25 hours on the reworked engine now and cruise from 65% and up. CHT?s have been better this time, not excessive, adj mixture to get EGT?s in the 1200?s. CHT?s initially in the 380 range now, 350ish.

I?m considering putting steel cylinders on now.
 
Chris, I'm not an engine guy so no comments on internal engine parts and what could be wrong, but I will make a comment on the amount of oil. I have heard that the majority of people running Lycoming don't top off their oil to more than 6 quarts because it just runs out. Try staying at 6 quarts so you have a good consistent number to measure without worrying about any of it running out.
I'm lucky in that my engine uses very little oil but if I put in 7 quarts, it will seem that she drank an entire quart in 1 hour of flight until it gets down to 6 quarts where she is comfortable at . . . She just doesn't like her belly to be too bloated :D
 
I'm lucky in that my engine uses very little oil but if I put in 7 quarts, it will seem that she drank an entire quart in 1 hour of flight until it gets down to 6 quarts where she is comfortable at . . . She just doesn't like her belly to be too bloated :D

+1 same here O320/160/FP
 
time to get on board with all engine musts, wobble test, cut open oil filters, bore scope, oil analysis, comp test, reading spark plugs, ect anything else i missed. ;)
anniversary-logo.jpg
 
I would post a picture but have been unable to in the past. Titan 370 with 230 hours on the engine. 5 hours per court of oil led me to borescope, it never changed from day 1. I saw oil pooling in two cylinders. That led me to have the engine honed and new rings put on. 20 plus hours into the new break in, the oil consumption went from 1 quart per 2 hours to improving to about 1 quart in 4 hours, now getting worse, 1 quart per 1.5 hours. They are Ni cad cylinders. I followed the new break in procedures. I used Phillips 20W-50 based on Titan's recommendation for the first break in and pure mineral oil on the second break in based on the engine mechanics recommendation. My engine temps are much improved on the second break in and it seems to be running well. I e-mailed Lycoming and they said Ni cad cylinders can take up to 50 hours to break in, I'm just getting discouraged since they appeared to improve and are now getting worse after 20 plus hours.

Who honed the cylinders? The ECI guidelines state that special stones are used for nickel cylinders, if I remember correctly. You can't used the std stones for steel cylinders? Might want to ask the shop how it was done and call Continental. Also pull a plug and look at the cylinder walls with a flashlight. If they have any light, tan/brown color to them, they are glazed and the source of your problem. If nice and shiny steel, they are not.

Larry
 
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