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First Start After Sitting A Year. . . Ideas?

J

Jbon

Active Member
My Lycoming O-360 has been sitting for a year while the airplane has undergone a complete panel and electrical system upgrade. Soon I?ll be starting the engine, and I have concerns about scuffing the cam lobes while waiting for oil to make its way to the top of the engine. I?ve always been told that this startup wear, particularly on what is probably a very dry cam, is responsible for a tremendious amount of overall engine wear.

In trying to come up with a way to mitigate the problem, my friend wondered out loud why I couldn?t just fill the case to the top with oil (through the breather), submerging the cam. Then drain it all out, pull the engine through by hand to insure no hydro lock issues, refill the case to the normal level and start?r up.

It sounded kind of crazy at first, but after giving it some thought, I can?t see why it wouldn?t work. I figure I must be missing something, and thought I?d run it by you guys. What do you think?

If you think its a good idea, I wonder how many gallons of oil it would take to make it to the top. Also, couldn?t you use cheaper automotive oil, since it?s going to be drained out anyway?

Thanks in advance for your input!
 
Something like that...

When I bought my engine for my last Rv, I did exactly that for storage. I bought a case of cheap auto oil and filled it to the top. Keep in mind that oil will come out of every hole. I had the carb and both mags off and made covers to seal the holes, don't forget the exhaust ports... Also, plan on pulling and cleaning the plugs too.
 
Interesting that the Lycoming service bulletin has you do all this cranking of the engine to purge the lines and build the oil pressure up. Great idea, but it seems like that could cause scuffing of the cam. On the other hand, perhaps. There will always be enough of an oil film to protect it during the relative low speed cranking.
 
Here's a slightly different procedure

I have a IO-390 mounted on my build and I've had the engine for almost two years. I have turned over the crank by hand a few times mounting the prop, working on the cowling, moving things around.

I had the same concern that I may have scraped the preservative oil off the cam lobes.

Lycoming suggested this to me (new engine):

1 Leave the preservative oil in the engine.
2 Remove the fuel injector throttle body from the from of the warm air sump and plug the hole. This to avoid oil getting into it and making a mess - reason: if there is oil above the level of the bottom edge of the cylinders, when the engine is turned over oil can get past the cylinders and through the intake valves and down to the warm air sump.
I opted to remove the sniffle valve and let any oil drain from the sump. Some oil will get by the pistons and down to the intake manifold, just don't want it to get into the throttle body.
3 Fill the engine with oil.
4 Remove all of the top spark plugs.
5 Turn the engine over with the starter. I am guessing it may turn about 150-200 rpm.
6 Lycoming said that should get the crank to splash oil up onto the cam shaft enough to add protection.

Sounds feasible. ?
 
Jbon said:
Interesting that the Lycoming service bulletin has you do all this cranking of the engine to purge the lines and build the oil pressure up. Great idea, but it seems like that could cause scuffing of the cam. On the other hand, perhaps. There will always be enough of an oil film to protect it during the relative low speed cranking.
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At overhaul, all bearings and cam lobes are coated with something closer to grease than oil. It doesn't drip off from gravity and is designed to lube for a much longer period than oil to survive the initial oil starvation issues seen at first start.

To the O/P, I would not bother putting several gallons of oil in the engine to lube the cam. The amount of oil left on the cam at one year is not much different than the amount of oil left on the cam at one month. The wear from this type of start is not what kills cams on lycomings; It is the corrossion that causes the problems and if you have it, there is no longer anything you can do about it.

Larry
 
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My engine sat for at longer than yours. I just followed lycomings pre oil procedure. It worked fine.

Ideally I would have put oil in it then rolled the engine upside down to oil the cam, then mount it on the plane. I thought about it, but couldn't find an easy/safe way to do it.

If you just follow Lycomings oil procedure you will be fine. It doesnt take long at all for oil pressure to build if you follow their procedure.
 
RV8JD said:
Lycoming SI No. 1241C "Pre-Oiling Engine Prior to Initial Start"
"Prior to initial start after engine change, overhaul, oil cooler replacement or draining or any prolonged period of inactivity."​
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*This* worked for me after 4+ years sitting idle. At starter speeds the cam will be fine with what little oil remains for the few seconds until more arrives. I have 30+ hours now and no issues and (so far) nominal oil analysis with clean filters. As stated above the spalling damage that kills cams (and engines) has its root cause in corrosion (which you may or may not have) not a few seconds of running “dry” at startup (while preoliling).

I strongly recommend you start with fresh oil, change at no more than 25 hours (10 probably better), cut the filter and inspect closely, and run an oil analysis. Perhaps overkill, but these actions made me much more comfortable that the unseen cam lobes were doing ok. YMMV.
 
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I pre-oiled mine using a pump sprayer from the garden dept at Home Depot. Cut the spray want off the pump sprayer output line and connect it to a short piece of aluminum tubing with an AN coupling sleeve and nut to hook up to your oil pressure sender fitting on the back of the engine. Remove the oil pressure sender line from the back of your engine and connect the pump sprayer line. Put about a quart of oil in the sprayer and pump it up. Oil will flow into the engine near the top. It may go quite slowly if you have a restriction fitting in the engine (which you should). Once the oil has pumped in mostly, remove the sprayer, reconnect the oil pressure sense line and start the engine. Don?t wait a long time for this engine start. When I?ve done this, I had oil pressure indication right away, and it didn?t fluctuate - which would indicate that you only pre-oiled the oil pressure sender..... Pressure indication was steady, and remained that way. I?ve done this on all three of my builds. The first one sat for over a year before first engine start. That engine now has 1500 hours on it and its running strong.
 
pjc said:
*This* worked for me after 4+ years sitting idle. At starter speeds the cam will be fine with what little oil remains for the few seconds until more arrives. I have 30+ hours now and no issues and (so far) nominal oil analysis with clean filters. As stated above the spalling damage that kills cams (and engines) has its root cause in corrosion (which you may or may not have) not a few seconds of running “dry” at startup (while preoliling).

I strongly recommend you start with fresh oil, change at no more than 25 hours (10 probably better), cut the filter and inspect closely, and run an oil analysis. Perhaps overkill, but these actions made me much more comfortable that the unseen cam lobes were doing ok. YMMV.
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+1

An engine assembled with the proper assembly lubricants should be able to spin on the starter for 10 minutes, on it's first start, or more without any wear to anything, except for the rings/cyl walls, which are designed to wear.

for an engine that sat for a year, I would probably pre-oil per lycoming SI. Much rather have the "dry time" at low RPMs. It will take x number of crank rotations to prime the system, so there is no short cutting, but low RPM should be slightly less wear potential. Externally pre-oiling, as described above, will greatly reduce or eliminate the number or rotations necessary for priming. I don't know the lyc's as well as chevy's, but it is quite possible the pump is tight enough to not lose it's prime over a year.

For new engines, don't forget the oil filter. The first quart delivered after the pump is primed goes to the filter, if it is empty.

Larry
 
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Would the “external” pre-oiling through the oil pressure sensor line/fitting fill all the internal oil passages as well as the oil cooler?

I guess, the oil will likely bypass the oil cooler due to the vernaterm valve being open at room tempratures. That’d also be the case with the pre-oiling per the Lycoming instructions, which is why they say to fill the oil cooler with oil. Am I correct? So, the oil cooler would need to be pre-filled with oil in any case.
 
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Kalibr said:
Would the “external” pre-oiling through the oil pressure sensor line/fitting fill all the internal oil passages as well as the oil cooler?

I guess, the oil will likely bypass the oil cooler due to the vernaterm valve being open at room tempratures. That’d also be the case with the pre-oiling per the Lycoming instructions, which is why they say to fill the oil cooler with oil. Am I correct? So, the oil cooler would need to be pre-filled with oil in any case.
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The bulk of the oil squirted into the described point will go straight to the galleries and into the guts of the engine. I suspect that some oil will make it to the circuits near the filter and ultimately to the pump, but not sure how much. It will likely fill those circuits downstream from the pump. I would expect NO oil to make it to the cooler or filter . The empty filter will rob all of the oil from the pump, once spinning, until it is full. The cooler will only rob some until full. This is why lycoming recommend pre-filling them


As I mentioned, on a new engine there should be no wear from spinning the crank for 30-60 seconds to allow for the oil pump to prime and fill the circuits. Make sure one plug is out of each cyl when doing that.

Larry
 
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Larry, thank you. On a new and never run engine, yes, it will have the assembly lube in all the needed places. I am in a situation similar to the OP where I have an assembled and run-in engine (and then preserved at the factory) that will have been sitting for a year by the time I hang and run it. It is an Titan engine and they drain the oil after the 3 hr run-in and don?t fill it with oil when they preserve it. No assembly lube is left after the initial run in.

Regarding the oil filter, I looked at the lubrication schematics in the Lycoming overhaul manual and it looks to me that the oil filter will get filled with oil if the oil would go upsteam towards the oil pump when the engine is pre-oiled from the pressure sensor port. As far as filling the oil filter with oil prior to installing it on the engine, it would be impractical with a 90 degree adapter, as is the case with my setup.

Since the oil cooler will need to be filled with oil in any case, I am thinking perhaps the ?external? pre-oiling could be done through either the inlet or through the outlet to the oil cooler. Once the oil cooler inlet or the outlet hose is disconnected, the entire system could be preoiled upstream and downstream of that disconnected junction. Including the oil cooler and the oil filter.
 
Kalibr said:
Larry, thank you. On a new and never run engine, yes, it will have the assembly lube in all the needed places. I am in a situation similar to the OP where I have an assembled and run-in engine (and then preserved at the factory) that will have been sitting for a year by the time I hang and run it. It is an Titan engine and they drain the oil after the 3 hr run-in and don’t fill it with oil when they preserve it. No assembly lube is left after the initial run in.

Regarding the oil filter, I looked at the lubrication schematics in the Lycoming overhaul manual and it looks to me that the oil filter will get filled with oil if the oil would go upsteam towards the oil pump when the engine is pre-oiled from the pressure sensor port. As far as filling the oil filter with oil prior to installing it on the engine, it would be impractical with a 90 degree adapter, as is the case with my setup.

Since the oil cooler will need to be filled with oil in any case, I am thinking perhaps the “external” pre-oiling could be done through either the inlet or through the outlet to the oil cooler. Once the oil cooler inlet or the outlet hose is disconnected, the entire system could be preoiled upstream and downstream of that disconnected junction. Including the oil cooler and the oil filter.
Click to expand...

While oil pumped in will circulate near the filter, it is unlikely any will get in it. Oil can only get to the filter via gravity from the pressure port. The filter inlet goes to the pump and is likely air locked. It seems highly unlikely any oil gets to the filter with that method. Not sure this is an issue though. Spinning the engine at a few hundred RPM for 30-60 seconds is not likely to damage or wear anything, assuming the plugs are out. Remember, your engine runs at 1000 RPM for ~5 seconds without flowing oil each time you start it and this happens hundreds or thousands of times before TBO.

As I mentioned, the oil drain down at one year is not likely any different than the drain down at one month. Your situation is really no different than most other starts. Remember, you start with an empty filter every time you change it. No need to overthink this. All will be fine. I would only bother with pre-oiling on an engine that wasn't previously run. Yours will already have the same amount of oil in it as you will experience each time you change your oil/filter; Which you will do many times without harm.
 
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Thank you. I hear you. I am just overthinking this as I am away from the project at the moment and have free time on my hands.

Besides, my engine has roller tappets, which, I suppose should reduce the friction with the camshaft even further.
 
Start up

I’ve been following this thread for a couple days. Today I followed the Lycoming instructions earlier in the thread. I filled the oil cooler with oil( took almost a qt). I pulled bottom plugs and swung prop twice for about 6 seconds each which built 35psi oil pressure. Put bottom plugs in, 3 seconds on the boost pump and she fired on the second blade. It ran ultra smooth from the getgo, even at idle. My AP/AI that was assisting said that it was the smoothest 540 that he has seen. Ohhh what a relief it is.

First time this engine has run since last March when we built it. Thank you Watson Aero. Louisville,GA
 
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