The International Cessna 170 Association

Thank you gentlemen for the thoughtful replies. I have been using the procedures that several of you have proffered and George, I am using straight mineral oil for break in. So far the cylinder temps are behaving well (have a egt/cht gage). But of course there is always the "next" issue. Prior to the overhaul my temps would border on redline. I have the original gage with just red and green. I also have the spin-on oil filter STC. With any significant climb (say 2000 feet) on a warm (say 85F) day it basically pegs the gage. I'm trying to fly in cooler temps with little climb but this does naturally have me concerned. I've read the threads that the older gages redlined at 225, but I'd like to hear from experienced folk here what they think and would do in like circumstances.

Well one thing i have done on a number of occasions before pulling the cylinders for overhaul of them etc,etc is pull the sump off and clean it . This is especially for an engine that have done a thousand hours in the last twenty years . Things you find in sumps is totally amazing also . The grey sludge and water you find is beyond belief. Plus it allows a check on the corrosion that's happening. I know of a process that where the area prone to corrosion is soda blasted clean and then cleaned with MEK and then painted with an poxy paint .[ipad will not let me put in the correct spelling ] . This stops the corrosion factor in the critical areas. Recently we pulled a sump off that was done 5 years ago and it was good as the day it was put in except the paint had yellowed a bit . Besides sludge we have found in sumps has been a very large split pin , smaller split pins ,washers , and a very old car key. The key had been originally chromed but the brass ??? Had started to break down . All these had been placed in a photo frame and hung on the office wall until it disappeared one day.

Well, allow me to back-pedal a bit on my previous posting...

I did not mean to imply it was OK to disregard any mfr's break-in recommendation. That comment was generically intended for OEM steel-cylinder and channel-chrome cylinders...not the newer processes which undoubtedly have special considerations by their mfr's. (And I posted that not having read Richard's pre-existing post that he used the X-country oil...it may have appeared I was disagreeing with him on that matter and I was not. My own rebuilds and engine work performed in my past have all been either new steel or channel-chrome....never an ECI or Ni-Ch cylinder, as those have not been my preference.)

I guess I should have specified that better.

Gents,

As it turns out I’m picking up my trusty steed this week after a post prop-strike incident in which I opted to pay the over and above for a full overhaul with Millennium cylinders. Amongst many options over the ensuing five months I did not choose to install a full engine monitor. I will have to rely on my oil pressure, oil temperature and EGT gauges to deduce how my break in is proceeding. I did install an EI fuel flow gauge.

My plan is to follow Hilltop’s advice for the first ten hours to include the use of OEM recommended break in oil.

Any other words of wisdom in the next few days are welcome. Thanks for the tips so far.

Jack,

No full engine monitor?

My words of wisdom. Savor the experience. You will be joining the ranks of tens of thousands of pilots who broke in their overhauled engine with no full engine monitor. And you can then tell the story to those young aviators just before leading into that other story about walking to school up hill both ways with no shoes.

Mid 2017 we overhauled our C-145 and used Superior cylinders. We used a secret formula of 4qt 40w and 4qt 50w Shell mineral oil. The secret is, is is what we had on hand.
We did nothing out of the ordinary other than running it harder than the normal hard running we usually do. This means we only pulled the throttle back to about 2600 except to land and we only did that to ensure we wouldn't exceed 2700. We did not exceed 3000 msl and most of our break-in was under 2000 msl.

Of course we monitored engine oil pressure and temps but saw nothing different than any other normal operation. About the only thing we did different besides 2600 rpm rather than 245-2500, is we checked our oil level religiously. And there is the rub. In 18 hrs of operation we lost a total of 1 qt of that special mix.

Normally oil consumption on break-in is high. Engines push out oil at a higher rate till broken in. Something in the rate of 2-3 quarts over 10-15 hrs. One just keeps replenishing it till the rate slows down to normal rates and then one proclaims the engine broken in.

So our engine only pushed out 1 qt and between 15-18 hrs my partner and I proclaimed the engine broken in.

As for the special sauce of half 40 and half 50w, I can only recommend it to those who find themselves in the pickle I was. I probably would have waited and bought more 50w but my partner Leroy, who has been breaking in engines for about 70 of his 80 years, was looking cross eye'd at me. What a pickle. I did at least insist we only use the same oil manufacturer, Shell, rather than a mix of Shell, Exxon/Model and BP he first pulled from the storage locker.

Thanks Bruce!

Weather looks good and we are off to Chatham to pick up 94D in the morning. I'll let you know how it went in about 10 hours or so. Now if I can only convince the better half that flying 10-20 hours on my bird is my JOB for the next week! ...

For the life of me I cannot figure out why page 2 and page 3 of this thread are identical. (Perhaps a moderator has inadvertently manipulated this thread? ...or there's a glitch in the software... whatever...)
Anyway.... Bruce, I'm curious about the reluctance to mix different brands of mineral/non-additive engine oil. Does Shell, Exxon-Model, and BP avoid adding the same non-additives to mineral oil..??? or do they not add different non-additives..?

Actually on very close examination you will find page 2 and page are not exactly the same. There are however many duplicate post on each and I think a few that only appear on one or the other page. For example the first post at the top of each page is different.

I have no idea how it could have gotten this way.

As to the oil, I have no idea if Shell, Exxon-Model, and BP mineral oil is exactly the same or different. That is where I drew the line. We would mix weight but not manufacture.

Over the years in our shop we have had all the brands of engine oil on the shelves. The oil reps leave a 5 gal drum as a sample in hope we will buy the oil in 44 gal drums. The oils we have used is shell, BP, Exxon, Total , Phillips , Castrol and about 3 other brands that I can’t remember [old age] . It’s my opinion that the very high time engines are telling the story on what to use in oils. Engines that use Exxon exclusively [cheap cost] have bearing issues [eg pitting]. While the best oil is Phillips . It has some corrosion inhibiter in it and a very stabile oil at high temperature . It does a very good job.
NOTE.. please Mr rep from Phillips , I need another sample .