One thing I didn't mention: besides the micro welding problem, if the cylinder walls get to hot early on the oil will form a hard glaze on the cylinder walls and the break-in process will stop. The only way to start over is to pull the cylinders and hone the bores again.
When you let it cool make sure it gets to the point where you can lay your hand in the barrels without any discomfort.
Break-in Oil: Mineral vs Phillips 20/50W XC
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Re: Break-in Oil: Mineral vs Phillips 20/50W XC
1. From Aviation Consumer....I don't recall the writers name........only the growing dis-satisfaction to hostility. I want to say.....right around late 1990's to early 2000's but I no longer recall exactly.
2. I'm happy that John added in some of the specifics on break in. It's not an "art", but it can be screwed up.
2A. Thankfully we've mostly moved away from Chrome cylinders. A nice idea that didn't work out.........
3. You have Superior cylinders. I have no idea if they make them the same as they did in the late 90's into the 2000's. If so, plan on a long (longer) break in. Don't be in a rush to pull the mineral oil until you're satisfied with A. Decreased oil temps and B. stabilized oil consumption.
4. One of many things(but not all) I agree with Mike Busch on is the use of borescopes in cylinders. If you have experience and know what to look for they will show if your cylinders are broken in, But........you need to look at many cylinders for comparison first. JPI(electronic engine monitoring) can do about the same thing. Within several hours cylinder head temps and oil temps should noticably decrease.
5. When I ran the shop(no longer do..........trying?? to be semi retired now) one of the phrases I dispised was........"well......we've always done it that way". Nothing like stopping inovation, critical thinking or original thought! However........ in this case, until something comes along that's better, or all ( or enough of) the industry determines it's 'ok' to use AD oil from zero hour forward, I'll continue down the proven road/track. There is simply too much time and expense to R&R cylinders, coupled with you (the mx shop) can induce problems by pulling cylinders.
2. I'm happy that John added in some of the specifics on break in. It's not an "art", but it can be screwed up.
2A. Thankfully we've mostly moved away from Chrome cylinders. A nice idea that didn't work out.........
3. You have Superior cylinders. I have no idea if they make them the same as they did in the late 90's into the 2000's. If so, plan on a long (longer) break in. Don't be in a rush to pull the mineral oil until you're satisfied with A. Decreased oil temps and B. stabilized oil consumption.
4. One of many things(but not all) I agree with Mike Busch on is the use of borescopes in cylinders. If you have experience and know what to look for they will show if your cylinders are broken in, But........you need to look at many cylinders for comparison first. JPI(electronic engine monitoring) can do about the same thing. Within several hours cylinder head temps and oil temps should noticably decrease.
5. When I ran the shop(no longer do..........trying?? to be semi retired now) one of the phrases I dispised was........"well......we've always done it that way". Nothing like stopping inovation, critical thinking or original thought! However........ in this case, until something comes along that's better, or all ( or enough of) the industry determines it's 'ok' to use AD oil from zero hour forward, I'll continue down the proven road/track. There is simply too much time and expense to R&R cylinders, coupled with you (the mx shop) can induce problems by pulling cylinders.
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edidin
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Re: Break-in Oil: Mineral vs Phillips 20/50W XC
Having broken in a number of Continental engines in the past few years, from C-85 to IO550, always have good success always starting with mineral oil, changing it out around 10 hours for more mineral oil, and then going to X/C around 20 hours.
75% first hour, 65/75% hours 2-5, then keep the power up. IMHO takes about 50 hours before an engine is fully broken in, and ideally those hours accumulate quickly in terms of calendar time. Seems to set them up well for longevity.
YMMV.
75% first hour, 65/75% hours 2-5, then keep the power up. IMHO takes about 50 hours before an engine is fully broken in, and ideally those hours accumulate quickly in terms of calendar time. Seems to set them up well for longevity.
YMMV.
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Re: Break-in Oil: Mineral vs Phillips 20/50W XC
I will also add that based on a recommendation from a couple IA friends and their engine shop in CO, I had my local shop hone the brand new Millenium cylinders. The CO shop experience was that there were some issues with Millleniums factory hone not being deep enough and glazing. The local shop said he had mostly seen that on the larger cylinders but of course was happy to hone my C85 cylinders. They also loaded the pistons for me which was convenient. I figured it was cheap insurance.
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