Don't flame me... but I really want to know what else I can do.

Darren S · #1 09-20-2010, 03:19 PM

Hi all,

My new to me -7 has 270 hours on it and the IO-360. It has a Superior XP engine. The manual says that the max oil consumption is 1 quart per hour. I am way below that at 1.5 quarts in about 20 hours.

Winter is coming up here in Canada and I've been pre-heating before first start. The log book says the compression was 76 - 78 on the last annual in April 2010. She runs fine as far as I can tell. There seem to be a bit more oil on the belly on the left side when compared to the right.

I really want to get the best life out of my engine,

So.... is there anything else I can to do ensure a long life ? I change the oil every 50 hours, because it has an oil filter. What else ?

I guess another way to put the questions is, "What did an owner do wrong to have to rebuild the engine or top at say 500 hours?"

I see it all the time on Barnstormer for example. An engine with a rebuilt head at only 500-600 hours. Was it run out oil ? Run too hot ? or is this normal despite the best engine care ? Is 2000 hour TBO just for the bottom of the engine and I should expect to have to overhaul the top at 500 hours ?

Sorry if these are dumb @ssed questions

Thanks,

Darren

JonJay · #2 09-20-2010, 03:25 PM

I "baby" my CHT's and considering 400 to be my "start doing something to cool them" point, but there is some debate about that low of a threshold.

I think most of the low time tops are planes that where not used regularly.
Fly often and keep that engine happy.

Ron Lee · #3 09-20-2010, 03:29 PM

Flying a lot should help as suggested. Since I no longer fly 250 hours a year, I use an engine dryer to pump dry air into the engine. That may prevent corrosion.

I use a 420 degree F CHT limit in mine. No justification. Still below the probable limits of 450 degree F continuous and 500 degree F absolute max.

Mel · #4 09-20-2010, 03:31 PM

Jon is correct in that "most" early top overhauls are caused by airplanes sitting.
Fly the airplane every week if possible. Try to keep the oil temp between 180-210*F and you should be able to reach or bypass TBO.

647jc · #5 09-20-2010, 03:33 PM

Some people advocate changing oil every 25 hours even if you have a filter on the engine. The extra oil on the left side of the fuselage bottom could be due to your oil breather tube exiting on the left side of the cowl bottom. Also, not sure how much oil you try to keep in the engine but often any more than 7 quarts will just get blown out the breather tube and end up on the belly of your plane. Not sure what else you can do to improve the health and life of your engine but I'm sure you will get a lot of advice.

Darren S · #6 09-20-2010, 06:41 PM

Hey thanks for the suggestions so far. I like what I hear. Fly often. That ain't a problem for me

Now that it was mentioned, I think the oil breather tube is just to the left of center. This could be why there is a slight bit of oil on the belly. My CHT's are always below 400 degrees F so that's good. And the EGT's I run at about 50 - 75 degrees ROP and I usually sit at 65% power (22 MP and 2350 RPM).

I use 100LL of course. I am at 25 hours since last oil change. It does look pretty black. I may just change it since I am changing brake pads and tires. Oil is cheap, engines are not...... one guy use to always tell me. I put in 7 quarts last time and now it's down to 5.5 quarts. I was told that anything over 6 quarts gets blown out so I didn't bother top up the oil.

Thanks for the help so far,

Darren

Scott Hersha · #7 09-20-2010, 08:22 PM

One thing I started doing, as suggested by Larry Vetterman, is changing my oil every 25 hours and changing my oil filter every 50 hours. This may be especially helpful in the summer when the oil breaks down a little quicker with the elevated temperatures. When I change it at 25, it still isn't black yet. 2700 RPM should only be used for takeoff or go-around, and only for a short time. 2700 is the max limit, but for a lot of Lycomings, 2600 is the max continuous. If you fly frequently and run your Lycoming at 65% or below for the majority of your cruise flight, and you take care of it mechanically, you should have no trouble reaching your TBO without a top overhaul.

penguin · #8 09-21-2010, 04:54 AM

There's a lot of personal preferrence in this subject! Aviation Consumer recommend changing the oil based on calendar time (every 6 months maximum, preferrably every 4), as well as on running time. That gets the corrosive build up of lead salts out of the sump. Agree that flying often is good

, although I would have no problem operating at 2700rpm all day, the only reason to back off is for noise. Also agree that 400F is a good max CHT. You could also consider running lean of peak (if you have all cylinder CHT & EGT monitoring) to reduce the temperatures - but read up on it first. I don't believe oil quantity to be an issue with regard to life, just how much is thrown out, I top up to 6 (or just over) and put another in when it gets down to 5.5. What oil do you use, I am using Aeroshell W80+? If you don't fly every week I think its important to use a + oil.

I found that my quick drain sump plug was leaking very slightly and putting a small streak down the belly, as well as the breather contributing (do you have an air/oil separator?). Apparently there are replacement O rings available for the quick drains (hot oil cooks the rubber and makes it hard).

senof28 · #9 09-21-2010, 06:54 AM

try this site. I fond the webinars very helpful.
http://savvymx.com/
Rick
9A

Scott Hersha · #10 09-21-2010, 09:57 AM

I misspoke. 2700 & 2600 RPM limits are for my prop (Whirlwind 200RV), not a Lycoming limit. I also have a no continuous operation range between 2050&2300, but again, that's a prop limitation. Max rated power for my O-360 is at the recommended engine limit of 2700 RPM, but there's no time limits on that as far as I know.