Ras Posted March 8, 2014 Report Posted March 8, 2014 After a major overhaul, I put about 60 hours on my O-360 engine using straight mineral oil. After 2 good oil analysis reports, 2 "clean" oil filters and stabilized CHT, I'm switching to Aeroshell W100. When switching from mineral oil to ashless dispersant, Lycoming recommends changing the oil after no more than 5 hours to look for signs of sludge. Is that really necessary? If so, other than cutting open the filter, where else do I need to look?
N601RX Posted March 8, 2014 Report Posted March 8, 2014 I also remove the screen and check it at each oil change. Some complain that it is to hard to get to and don't bother with it, but after doing it a few times it's not that difficult. I start with piece of safety wire about 4 ft long and use the shaft style twister with the 2 small holes in the end of it instead of the plier type. Once twisted, then cut the extra wire off. With some practice it only takes a few minutes.
Guest Posted March 8, 2014 Report Posted March 8, 2014 The lycoming recommendation is when switching an engine that has been on mineral oil for much longer than just break in. You should have no concerns after 60 hours. Clarnece
aaronk25 Posted March 8, 2014 Report Posted March 8, 2014 Why break in on mineral oil some engine builders recommend Philips 20w50 non mineral oil. Doesn't the mineral oil accelerate wear on high pressure contact surfaces such as the cam and lifters? Hasn't it been proving that cylinder walls and rings break in fine on conventional oil as long as power settings are high? 1
Bob_Belville Posted March 8, 2014 Report Posted March 8, 2014 My engine had run only Aeroshell 100 for 700 hours SN but the engine shop guru who just rebuilt it after a prop strike recommends running the 1st 10 hours on Phillips 20W50 M for 10 hours @ 75% power to set rings, change oil and filter to the same multigrade mineral oil, for 15 hours then change oil/filter. After another 25 hours on mineral oil, we're to go to Phillips 20W50 XC, (ashless dispersant) The engine is running great and seems more powerful. I am going to heed his advice.
PLN_FXR Posted March 9, 2014 Report Posted March 9, 2014 I won't get into the Phillips vs Aeroshell debate at this time, but following overhauls I generally run my customer's aircraft +/-10 hours on Mineral Oil, then change to Ashless Dispersant. There is no sludge build-up in that amount of time, and the rings will have set in properly (generally, they will seat in less than an hour). I would not try to break in an engine on, for example, 15W50 Aeroshell, as the semi-synthetic formulation doesn't lend well to rings seating properly. 1
Guest Posted March 9, 2014 Report Posted March 9, 2014 Lycoming SI 1014M has the recommended oil grades for operation including break in. I find it interesting that when I first started fixing airplanes only the H2AD engine had camshaft troubles, now almost all Lycomings do. At that time engines were routinely run on mineral oil for 50-100 hours for break in. Most of these engines had a nice golden coating of varnish on everything and seldom a camshaft failure. I've always wondered if the rush to get off mineral oil has anything to do with it? Clarence
PLN_FXR Posted March 9, 2014 Report Posted March 9, 2014 Lycoming SI 1014M has the recommended oil grades for operation including break in. I find it interesting that when I first started fixing airplanes only the H2AD engine had camshaft troubles, now almost all Lycomings do. At that time engines were routinely run on mineral oil for 50-100 hours for break in. Most of these engines had a nice golden coating of varnish on everything and seldom a camshaft failure. I've always wondered if the rush to get off mineral oil has anything to do with it? Clarence I'm not sure about aircraft oils, but formulation changes in automotive oils have caused problems with "old technology"i.e., non-roller cam equipped classic cars. Federal mandates caused the zinc to be reduced/removed, leaving the cams susceptible to premature wear. Perhaps the same mandates have been applied to aviation oils?
aerobat95 Posted March 9, 2014 Report Posted March 9, 2014 I know aircraft and car engines are different but is it because these engines use 70 year old technology that they require a break in? My 2014 car just works.....heck my 2002 car worked with no special oil or breakin and ran fine for 11 years. Just seems like our aircraft engines should not be as finiky as they are. Back in the day did you have to break in a 57 Chevy?
DonMuncy Posted March 9, 2014 Report Posted March 9, 2014 I don't know what the factory did with cars in the 50s, but if you replaced the rings in an engine, the ring manufacturer specified how they were to be broken in.
Marauder Posted March 9, 2014 Report Posted March 9, 2014 Back in the day did you have to break in a 57 Chevy? Yep... Even today some vehicle break-ins are specified. Like, don't maintain a constant speed or to brake gently for breaking in new pads and rotors. Here is the break-in procedure for my 2011 F350: NEW VEHICLE BREAK-IN Your vehicle does not need an extensive break-in. Try not to drive continuously at the same speed for the first 1,000 miles (1,600 km) of new vehicle operation. Vary your speed to allow parts to adjust themselves to other parts. Drive your new vehicle at least 500 miles (800 km) before towing a trailer. Make sure you use the specified engine oil by checking the engine oil specification chart under Engine oil in the Maintenance and Specifications chapter. Do not add friction modifier compounds or special break-in oils during the first few thousand miles (kilometers) of operation, since these additives may prevent piston ring seating. See Engine oil in the Maintenance and Specifications chapter of this supplement for more information on oil usage. 2
Recommended Posts