Engine/prop overhaul

[olyolson]

My -8 has a little over 2000 hrs on it and the engine was assembled and installed in 2000 by master engine builder Seth Hancock. I have had no issues, it?s running well and compressions are all high 70s. Nothing significant on oil analysis so I?m going to keep flying it for a while. Just replaced the crankshaft forward seal so it?s all good for now.

I know, why overhaul it if it?s running well but just starting to think about doing it soon. I live in the St. Louis area so anything close by is good. I did price an overhaul by Poplar engine shop in Illinois but the cost of overhaul is almost the price of a new engine from Vans (still qualifies since the airplane never had this option exercised).

Anyone recommend a REASONABLE shop to do the overhaul?

[Mel]

Originally Posted by olyolson

My -8 has a little over 2000 hrs on it and the engine was assembled and installed in 2000 by master engine builder Seth Hancock. I have had no issues, it?s running well and compressions are all high 70s. Nothing significant on oil analysis so I?m going to keep flying it for a while. Just replaced the crankshaft forward seal so it?s all good for now.
I know, why overhaul it if it?s running well but just starting to think about doing it soon. I live in the St. Louis area so anything close by is good. I did price an overhaul by Poplar engine shop in Illinois but the cost of overhaul is almost the price of a new engine from Vans (still qualifies since the airplane never had this option exercised).
Anyone recommend a REASONABLE shop to do the overhaul?

Treated properly and flown regularly, Lycoming engines have a history of running great up to 3,000 hrs. and beyond.
The recommended 2,000 TBO is just that, a recommendation. Of course it's your engine, your call. And when an engine begins to show signs of wearing out, it typically gives lots of warning.
Just my $.02.

[mike newall]

Totally agree. If it is making power, not using oil, then carry on. Our engines on our skydive aeroplanes went to 3,000 hours. A carrier in the UK had a Lycoming O-540 that went to 5,000 hours before overhaul. It had top ends every 1,000 hours though.

Props - they need a look at every 6 years, even if it is just a strip, grease and reseal. Lots more whizzy bits and stress

[JDeanda]

Old A&P here... In Mike Busch?s book, he tells of a pair of turbo Continentals on his personal Cessna 310 that ran triple the TBO... BUT, those engines ran often, were kept cool, always had clean oil, were on oil analysis, got compression checks, were often borescoped and engine analysis data were downloaded and analyzed at regular intervals. That said, running beyond TBO happens fairly often in engines operated under FAR Part 91. Under Part 91, TBO is not regulatory. Under the right circumstances, I think it?s fine, practical and safe. I?ve seen a few motors run past TBO and they were fine. Well, leaky, but fine. Two things to consider: 1. If you?re planning to sell the airplane, a high time engine can lower the airplane?s value drastically, especially if it?s beyond TBO. 2. More importantly, if something bad happens and you end up in court, much will be made of the fact that you ran an engine over the manufacturer?s recommendation, fairly or unfairly, even if it had nothing at all to do with whatever problem is being contested.

[scsmith]

the AEIO-320-E2B in my old Citabria 7KCAB went 3200 hrs, most of that time towing gliders with the oil temp in the yellow but the CHT pretty cool. It flew almost every day. When we overhauled it, my partner (an A&P) and I kept looking at each other asking why are we overhauling this engine that looks like new inside.

[Ironflight]

Originally Posted by scsmith

the AEIO-320-E2B in my old Citabria 7KCAB went 3200 hrs, most of that time towing gliders with the oil temp in the yellow but the CHT pretty cool. It flew almost every day. When we overhauled it, my partner (an A&P) and I kept looking at each other asking why are we overhauling this engine that looks like new inside.

I?ve been pulling apart our RV-6 engine this week, getting the bottom end parts ready to go to Tulsa, and was pleasantly surprised that the tappet bodies and cam still have mirror-finishes. Yeah, the thought of ?why?? Has crossed my mind, but this engine came out of the Lycoming factory in 1992, and yup - its now a bit of a seeper and leaker.

Remember that overhaul happens not just on hours, but on time as well - and sometimes, it is time (especially when the engine is already off and you have four brand new jugs just sitting there looking for a home). I?m just hoping that cam and Tappers are harbingerS Of good news about the crank!

Paul

[Kyle Boatright]

Originally Posted by Ironflight

Yeah, the thought of ?why?? Has crossed my mind, but this engine came out of the Lycoming factory in 1992, and yup - its now a bit of a seeper and leaker.

Paul

Exactly. It isn't just the metal parts that drive a rebuild. Seals get old - some can be replaced externally. But those o-ring seals around the through-rods? Can't easily replace those. The thread and sealant between case halves? Same thing.

Can a leaky engine be perfectly safe? You bet. But they do make you wonder what else might be going on inside, and peace of mind has value.

[Pilot135pd]

Originally Posted by Kyle Boatright

Can a leaky engine be perfectly safe? You bet. .

Sheesh, the Franklin engine I had on my helicopter leaked so much I never looked at the dipstick. If it stopped leaking I knew it was time to add oil, and it ran like a fine tuned top !

[DTARM1]

If an overhaul cost within 50% of a new engine that's a no brainer. Get a new engine.

Research the FAA's definition of overhaul, rebuilt and NEW.

New = all new parts
Rebuilt = the parts are within tolerance (metrics) of acceptable

the difference between rebuilt and overhaul, the rebuilt has been 0 timed because it's been tested on a bench stand.

New vs. Rebuilt = rebuilt, even from the factory - you get used parts - as long as they meet manufactures' metrics. New - all new parts.

Continental had an engine failure that killed a doctor in Colorado. The Continental rep researched the crankshaft from the rebuilt engine. The crankshaft had literally broken in two. The continental rep found the crank had over 10,000 hours on it. Metal fatigue is something no body, no eddy current, no magnetic particle inspection, nothing can find - according to the rep (he only told me that story because he retired from TCM)

Anyway - get a new engine if you can afford one.

RV-8
B.S. in Criminology
27 yrs, 5 mo, 25 days in the Army
A&P, IA (trained at a university - not AIM or 3 years sweeping a floor or having my buddy sign me off). I got mine the old fashion way, I studied my *** off, graduated 1st in my class of 25.