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Oil Level in your RV

JonJay

JonJay

Well Known Member
My engine has always spit out anything above 6 1/2 qts through the breather (can you say dirty belly). I had reasonable oil burn at around 1 qrt per 5 hours, or so I thought. I decided to let my oil down to 6 qts, with little change. Now, over the past few months, 5 1/2. My "oil usage" is now down to less than a quart every 10 hours. So, obviously anything above 5 1/2 qts is getting thrown overboard, or?

I am curious as to what others are finding. I did raise the tail to flight attitude and it made very little difference on the level shown on the dip stick.

I am just fine keeping it maintained at 5 1/2 qts unless someone tells me something different. Seems to be the right level for my engine.

Aerosport Power, Superior, IO-360.

What are you seeing?
 
My Lycoming is young and always on a diet. I trained it well but it spits oil anyway even at 3 qts. On my recent big trip I started with 5 qts and after 53.3 hours of flight time ended a tad below 3 qts. No oil refill on the way. :D



Edit; O320 btw
 
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Same here with an O-360 narrow deck.

If I put in more than 6 all it does is spit it out. Costed me a bunch of $ and tons of cleaning till I figured that out. I thought I had marginal oil consumption and since I have chrome cylinders, figured I would have to live with it.

Once I stopped putting in more than 6 and never top off till it gets to 5 averaging somewhere around 5.5, my oil consumption has went way down.

The belly stays clean much longer now.

I guess I could add Allen's separator to the mix to allow me to run more oil for safety but not sure that is really needed?

Anyone got any comment on the pros and cons of running more or less oil in the sump other than the obvious issue with it spitting it out the breather?
 
I have the same with the ECi IO-340. keep it around 6 qts and it is pretty happy. More than that and I have a mess to deal with.
 
Required oil capacity ...

During the EAA webinar on engine oils a few months back, the statement was made, "4 cylinder Lycoming engines will run fine on anything above 4 qts". While I would not try running mine on 4 qts, it certainly supports maintaining the level at 6 qts to eliminate the venting/oily belly problem.
The flying club I was in for the past 7 years had an ironclad rule to not fill any of the 172s (one O-320, two O-360s) above 6 qts. All their engines run fine to points beyond TBO without problem.
 
Mine is an IO-360-A3B6D. When I change the oil and filter, I put in 6 quarts. Winds up being a little over 5 on the dip stick and stays that way. I burn a quart every 10-15 hours and it doesn't spit anything out.
 
I worked my way down from 7 when new:eek: I was also chasing high oil temperatures and was trying to use oil quantity as a high temp buffer. I fixed the oil temp problem (bigger cooler with more fin area). Now I fill to 5 1/2 and when it gets to 4 1/2 I add a quart. It takes about 15hrs to get there. IO360 B1B, cruise power is 2300 to 2450. When I cruise using higher RPM I spit out more oil.
 
Happy at 5 1/2 qts

This is a timely post. I was thinking of asking the same question.

I have 130 hours on my IO-360 and the oil level seems rather stable at around 5 1/2 qts. If I add more within a few hours it is down to 5 1/2 and stays there.
 
5 1/2 works best for me

My IO-360 M1 does best at about 5.5 quarts. I add one when it gets down to about 4.5. It seems to use a quart about every 15 hours.

Dan Miller
RV-8 Superior IO-360 M1. 1200+ hours
 
Test the theory...

JJ,

I target 5 - 5.5 Qts on the stick and the belly sees only a small amount. (The smoke system serves to clean that off everytime it's used... :rolleyes:) If I'm doing long X-country work, I'll fill it to 6. For folks in hotter climates or who are running the IO-360-A* 200 HP angle valve motors, you may want to run a slightly higher level to counteract the higher oil temps. The piston squirts on those engines use the oil as an additional cooling medium.

I recently ran a test on my IO-320-D1A to determine if the oil was being blown or burnt. I rigged up a small catch can with a shorter breather line to collect anything that was going overboard. Filled the oil to 6 qts, and then flew for 1 hour. The amount of oil that was collected was less than half of a thimblefull. Suprisingly not that much. So it meant that my increased consumption (1qt/5 hrs) was probably being burnt. With that and all of the other evidence collected, the cylinders are coming off for inspection and a TOH. Here's a pic of the Hi-Tech collection system...:rolleyes:

2012-10-07_14-19-40_646.jpg
 
0-320 RV-9a

I run mine between 6 and 7, with almost nothing ever on the belly. On a x-country I topped up to 7.5 and blew a part of that out.
do I recall..... Lyc. says to run with no more than 8, and no less than TWO?
what they heck kind of advice is that?
are the guys blowing or burning more running at higher rpm, or banking more than 20 degrees?
what's the diff?
 
Joe Blank said:
I recently ran a test on my IO-320-D1A to determine if the oil was being blown or burnt. I rigged up a small catch can with a shorter breather line to collect anything that was going overboard. Filled the oil to 6 qts, and then flew for 1 hour. The amount of oil that was collected was less than half of a thimblefull. Suprisingly not that much. So it meant that my increased consumption (1qt/5 hrs) was probably being burnt. With that and all of the other evidence collected, the cylinders are coming off for inspection and a TOH. Here's a pic of the Hi-Tech collection system...:rolleyes:

2012-10-07_14-19-40_646.jpg
Click to expand...

I know that how the vent tube is positioned can have a big effect on how much oil is sucked or blown out. In my case, if I go above 6 I get raw oil on the belly and it drips out of the tube afterwards. This makes me believe that I am not burning it.

My tube extends down and back between the exhaust pipes and sticks about an inch past the cowl. I have a 1/4" hole drilled in the tube about 5" up from the end. Not sure if my setup is optimal for reducing the amount that is blown/sucked out. A buddy of mine had his per the plans/manual basically dumping out right on an exhaust pipe. This led to a nasty brown residue on everything under the cowl and on the firewall so I decided not to follow his setup. He ended up changing his to something different after cleaning up the mess.

Wonder if the fact that you had that tube in a cup with no suction/pressure on it that it skewed your results?
 
O-360

5 1/2 quarts is the magic number for my O-360 A1* with dual P-mags. Any more just ends up being cleaned off the belly. 1 quart every 10-12hrs.
 
Same Superior engine in mine is happiest at 5-6 quarts. Start around 6 and add a quart when it gets to 5 (takes ~25 hours).

Greg
 
Very happy with this thread, above 6 qrtrs it spits outs the extra oil, seems to be happy at 5 1/2, although manual says minimum is 6, Lycoming IO360 M1B. Flying over the Caribbean & Amazon, I did waste some oil trying to keep it at 7qrts, couldn't risk it.
 
I was happy at 6

usually let it get down to 5 before dumping another one in. Having seen this post I might let it down to 4 1/2. I am running a Narrow Deck 0-360 with chrome cylinders burning/puking around a quart every 7 hours.

Randy
8A
 
At oil change, I put 7qt into the O320 and after first engine check, it is right about 6.5 (given it had to fill the oil filter and anything else). I then do not worry unless it see below 5.5 qts. By the time I need to think about adding oil, It's 50 hours and time for the next oil change.
 
I wish I could find the reference right now, but I'd heard a number of times that Lycoming says the O-320 will run fine with as little as 2 qts in the sump, so I stopped trying to keep mine at 7-8. I've let it stabilize at about 5.5, I don't add more until its below 5. That's averaging about 0.5 qt between changes.
 
Snowflake said:
I wish I could find the reference right now, but I'd heard a number of times that Lycoming says the O-320 will run fine with as little as 2 qts in the sump, ....
Click to expand...

It is in the engine operator's manual. The minimum safe quantity in sump is 2 US quarts.
 
I asked a Lycoming representative about this years ago. I have an O-360-A1A. The rep said fill it to 6 qts -- anything above 6 will just get blown out. I have followed his advice, keeping the level between 5 and 6 qts. I burn a quart about every 13-15 hours (Hobbs).

Chris
 
My factory new O-320 D1A (420 hrs) seems to be happy at around 5 qts. I add a qt about every 10-15 hrs if the level drops below 5 qts.

Peter K
9A-420 hrs
 
oil level in your RV

Could those of you who are engine people, and really know their stuff, please confirm that running our 4 cylinder Lycoming engines with around 5 or 6 quarts as measured by the dipstick is really okay for longevity and save efficient operation... and that we won't be doing any damage to our engines. I had been under the impression that keeping the oil level between 6 and 7 quarts (never going below 6 quarts) was the best choice for low maintenance and engine longevity.

Guidance on this issue will be greatly appreciated.

Thanx.

Victor
 
vasrv7a said:
5 or 6 quarts as measured by the dipstick is really okay for longevity and save efficient operation
Click to expand...

Been doing this for years. No problem.

Probably ought to explain why this phenomena occurs, so people understand why 6 qts. works better in a lyc.

All of the oil being returned to the sump falls thru the slots at the bottom of the case. When the sump is any more full than 6 qts, oil is hot and nearly water thin, can easily pool near the ends of the slots particularly when the aircraft is in a climbing or descending attitude. Combined with a fairly rapid flow of oil from the engine running the crank webs hit the pooled oil which splashes it and turns it into mist. It then goes out the breather. With the oil at 5-6 quarts the pooling of the oil doesn't occur.
 
5-6 Qts Best

On my 0-360-A1A, with 400 hrs TT and a CS prop, I find anything over 6 qts on the stick just pumps right back out onto the belly. I've ended up just using 6Qt when doing an oil & filter change, that gets me about 5.7 Qt on the stick, and I still get some on the belly. It seems that about 5.0 QT on the stick is where my engine is happy and stops venting it overboard. I still run normal oil temps at that level, though my installation has always tended to run cool - too cool sometimes - in that regard
 
Sounds like (unless I hear something to the contrary) I intend to switch and run my oil level between 5 and 6 quarts... learning new stuff everyday:)

Thanx.

Victor
 
vasrv7a said:
Sounds like (unless I hear something to the contrary) I intend to switch and run my oil level between 5 and 6 quarts... learning new stuff everyday:)

Thanx.

Victor
Click to expand...

Wish I was that smart. Took me 500 hours to catch on. Didn't think twice about what I was taught years ago. Check oil: fill up to level. Sheez.
 
oil level

5-6 quarts. Match cooling mods with needs.

Some RVer's route the crankcase breather vent to a rubber to metal pipe aimed near the end of the exhaust pipe, to vaporize the vented oil mist. Belly stays clean.

Many RVer's do this trick. I am not the expert on this. I am reporting that after using this for years, it has worked flawless for me.

Do a search and contact some one to properly understand the vent trick safety issue, prior to trying it.

IO-360 5-6 quarts
 
Still Breaking In, Dipstick Calibration

So I probably am using and/or spitting more oil because I'm only 15 hours into my actual flying my new engine.

Recently, my cold (70F) ECI IO360 dipstick showed 4 so I added one 1 quart container of oil. Let it sit for a few minutes and the dipstick showed ~6.5.

could it be that far off?

BTW, my Lycoming manual says 2 quarts is the "Minimum Safe Quantity in the Sump". And burning .4 to .8 quarts/hour is max oil consumption.

Does anyone routinely fly with 4 quarts on the stick?
 
Level

I keep topping off back to 7 qts and the belly was covered in oil. Now I let it ride at just under 6 and it doesn't ever seem to use any oil.
 
Rough engine at 4 qts?

I know Lyc says a 320 or 360 can run with only 2 qts, but has anyone experienced a rough engine when down around 4 qts? My engine seems to run a little rough at four and happy at 4.5 or more even though the oii temp and pressure is fine.
 
The Antisplat oil sep mod works great

This spring at annual time, I added the Antisplat oil Sep and vacuum valve and the oil level is stable right at the top mark on the dipstick and the belly is clean. Have about 70hrs since April and added one qt between the first 50hr oil change a 1/2 qt at a time to keep it in the top half of normal. To me that looks pretty close to "ideal" usage to avoid an early TOH. Should also mention that dipstick is calibrated for 5-6 qt on O-320.

I have checked the vacuum valve discharge and it is pristine clean. I have not spoken with Alan, but it would be my speculation that the folks that have had issue with fouling, are likely running Lyclones up at 7-8qt and spitting out so much that the 1/4" return can not keep up.
 
Yup. Every piston aircraft engine I know of will tell the operator exactly how much oil it wants. Anything more and it will spit it out at you. No two are exactly the same. I have a IO-540 I keep at 7.5 with 1800 hrs in a Comanche (little over half on the dipstick).

Point is every engine will talk to you and tell you how much oil it likes.

Jim
 
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