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Oil consumption just increased!!??

I initially liked some of Mike's early writing on maintenance. I have never talked to Mike personally. Just his underlings. His company basically preys on fear and perpetuates the myth that aircraft mechanics, on the whole, are shady at a minimum and flat out incompetent and dishonest at the worst.

I've noticed the same. Unfortunately, fear-mongering with "them" (insert: trade, race, nationality, religious affiliation, whatever) playing the bad guy is an effective technique for building a base. None of it has to be true, just believed.

Mike was a successful computer guy, then a writer. Clearly very intelligent, and a terrific promoter. That said, as an item of curiosity, does anyone know if, or where, he has ever actually worked as an A&P?
 
All these numbers are foreign to me. My O-290-D2 has about 350 hrs. TTSN on it and still burns less than one quart every 25 hours. My cylinders are Cermichrome. I fly with 7-1/2 to 8 qts of oil and never blow any overboard. I have an air-oil separator draining into a catch bottle and it only accumulates ~1/2 oz. of oily fluid every 25 hours. My dipstick is only mildly brownish at the 25 hr. oil change. Seeing oil consumption numbers like the OP is experiencing would scare the heck out of me. From the symptoms, there is excessive blowby for some reason. Yeah, you need to borescope the cylinders for sure.
 
What did you find when you got the jugs off?

Shallow pitting on the cylinder walls, as we saw with a borescope. Rings looked fine but we replaced them anyway of course.

Inside the case looked good, no spalling on the cam lobes or anything else obviously amiss there or with the cylinders so I just had him re-hone them (still within 'new' limits), for a lot less $$ than overhauling or new.

This engine only has 1500 hrs but that's over a span of 20 years. And while my hangar is relatively dry, it's also less than 1/4 mile from the pacific ocean. To help things last longer I'm going to be looking at doing something like a DIY engine dehydrator as seen in Sport Aviation and other posts on this forum.
 
If I got 1500 hours over 20 years before having to merely do a top end, I would consider that like making it to TBO. Keep doing whatever you're doing!!:)
 
This is from my O320 operators manual:
SECTION 3 LYCOMING OPERATOR’S MANUAL OPERATING CONDITIONS O-320 SERIES
OPERATING CONDITIONS (CONT)
Fuel Max. *Max. Cons. OilCons. Cyl.Head Operation RPM HP Gal./Hr. Qts./Hr. Temp.
O-320-A, -E** Series
Normal Rated 2700 150 ------ .67 500°F(260°C)
Performance Cruise (75%Rated) 2450 110 10.0 .37 500°F(260°C)
EconomyCruise (65%Rated) 2350 97 8.8 .33 500°F(260°C)

O-320-B, -D† Series
Norma lRated 2700 160 ------ .72 500°F(260°C)
PerformanceRated (75%Rated) 2450 120 10.0 .40 500°F(260°C)
EconomyCruise (65%Rated) 2350 104 8.8 .35 500°F(260°C)

Check the maximum oil consumption that Lycoming thinks is normal and compare with yours to see there if is real reason for alarm.
 
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Check the maximum oil consumption that Lycoming thinks is normal and compare with yours to see there if is real reason for alarm.

Definitely. My operators manual for O-360-A1A shows max oil cons. qts/hr. of .44 at economy cruise of 65% power. I fly more like 55% and was getting close to that at .35 qts/hr.

So, not enough to push the panic button but getting close, and with pitting showing on the cyl. walls, and after discussions with the engine shop, and it's winter so a good time to take care of it, I decided it was time.
 
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