I've been bugging my friend who is an A&P IA to let me shadow him on the reassembly of an engine, to help me decide whether it's within my grasp to build up my own powerplant for the Bearhawk (do I want to?) He's building a new Continental O-470 for his Skywagon, so I finally got the call. Let's assemble some engine!

The crank and camshaft had already been installed, and the case halves rejoined. Most of my questions at this point were about the steps to get to this point, with finding a suitable candidate core for overhaul, and how to go about getting stuff yellow-tagged. The inspection for even the slightest pitting and corrosion can disqualify a part from reuse. We tallied up about $24K in parts alone. That's why your engine overhauls are so insanely expensive.

The traditional Continental colors are a thing of beauty.


Freshly manufactured new crankshaft, hungry for oil.


New rods for the 470-R along with fresh Babbitt bearings.


Using a scale, the rods are weight matched into pairs for best horizontally opposed balance.


Wrist deep in some bottom end.


Rods installed and torqued.


Brand new ECI Titans with nickel carbide barrels. They ship with the piston already ringed and installed, but it's important to verify the piston weights and ring part numbers. Too little ring gap and you've got a recipe for cylinder galling.




Pristine head and valves. It'll never look this nice again.


Same for this guy.

I love engine assembly and is one reason why I want an experimental. I really enjoyed helping with assembly of the C85 I had, same with watching Steve at Steve's Aircraft assemble the O320 for his cub.

If this friend you know will help you assemble your engine I say go for it Z.

Zane,

Did your wife make you get a haircut for your 40th birthday?

akgreg wrote:Zane,

Did your wife make you get a haircut for your 40th birthday?

Well played Greg!! Well played!

Zzz wrote:New rods for the 470-R along with fresh Babbit bearings.

Whenever I hear the term Babbit metal, I always crack up.
When I was doing my training, all the old boys used to call it "White" metal out of habit. Apparently the trade name got changed, because it wasn't politically correct. Sometimes people get carried away.

Battson wrote:

Zzz wrote:New rods for the 470-R along with fresh Babbit bearings.

Whenever I hear the term Babbit metal, I always crack up.
When I was doing my training, all the old boys used to call it "White" metal out of habit. Apparently the trade name got changed, because it wasn't politically correct. Sometimes people get carried away.

According to this it's a clarification thing, as "white metal" may refer to a number of alloys. Plus it was invented by Isaac Babbitt.

$24k in parts...yowsa.

What are the biggest items that spell the difference between a $16k field overhaul and a $25k overhaul?

Very cool post, Z!! My partner just received his funds for his plane he sold and now getting ready to rebuild our 470. I sure hope I can be part of some if the rebuild and annual process to learn more about the Skylane.

If you can, I think it would be very beneficial to be part of a rebuild process to learn more about the inner workings of the engine.

lesuther wrote:$24k in parts...yowsa.

What are the biggest items that spell the difference between a $16k field overhaul and a $25k overhaul?

6 new ECI Titan cylinders @ $1800 (?) each, 10,800. Apparently a new crankshaft also in this instance more than makes up the difference methinks

Halestorm wrote:

lesuther wrote:$24k in parts...yowsa.

What are the biggest items that spell the difference between a $16k field overhaul and a $25k overhaul?

6 new ECI Titan cylinders @ $1800 (?) each, 10,800. Apparently a new crankshaft also in this instance more than makes up the difference methinks

Add machine work, new rods, cam, lifters, and all the fasteners. It's essentially a brand new engine from A to Z.

Thanks for noticing my fresh shearing

Zzz wrote:[

According to this it's a clarification thing, as "white metal" may refer to a number of alloys. Plus it was invented by Isaac Babbitt.

Wong again Zane. It was Bubba Babbit

Tim

The crank and camshaft had already been installed, and the case halves rejoined. Most of my questions at this point were about the steps to get to this point,

I still remember when my Mom helped me get the case halves aligned when I put them together in the basement. Used anaerobic compound to lay the silk thread in.

How well have people's field overhauls lasted compared to a total rebuild? I know a guy who got almost 3000 hours on his 470-R, from just a field overhaul and a top end at 1600 from his mechanic, and another guy who had a lower end failure at 600 hours from a reputable exchange. I know guys with zero problems on very expensive factory remans. It seems all over the map anecdotally, so it would be interesting to see what the reality is. I had to replace all my cylinders that were new at the rebuild, and knock on wood, these rebuilt exchanges are doing better than those.

I don't like pinching pennies on stuff like this. It just have no idea what is the most cost effective way to make sure I have the safest engine possible is.

Is there a big difference in safety and longevity between a good field overhaul and a reputable exchange?

I've run a whole bunch of big bore Continentals from in the crate to TBO, both from the factory and from small shops.

My rule of thumb for my work flying, 5-8 hours a day, 7 days a week, was if the first 30 to 50 hours was trouble free the engine would go to TBO trouble free.

Sad thing was, at TBO the engine would be running it's absolute best and I trusted it. New engines made me nervous as shit, and always ran auto-rough in wx or at night for quite a few hours.

In my personal airplanes not so lucky. Flying 100 to 200 hours a year there's always something FUBAR. Sitting kills them.

Gump

Zzz wrote:I've been bugging my friend who is an A&P IA to let me shadow him on the reassembly of an engine, to help me decide whether it's within my grasp to build up my own powerplant for the Bearhawk (do I want to?)

Give Swingle a call. He's got an amazing resource to help him and was still about ready to chuck the thing to the curb when I visited. Not saying "don't do it". Just that he would be a good resource to talk with about some of the potential downside.

Zane what dash number 470 is that engine-- K, L, R ?

hotrod150 wrote:Zane what dash number 470 is that engine-- K, L, R ?

Eric, it's a -R.

I watched my builder assemble mine about 5 yrs ago, very cool.

Pponk was a $25k mod back 5 years ago that was new ECI cylinders polished and flow balanced all the machine work to the case, Mags, vac pump, Carb rebuilt, rebuilt oil pump, oil cooler, starter adapter and more. And cost of the STC. Not suggesting it just comparing. Now (today) the Pponk is $29.9K

Very cool, Zane! This is something I've wanted to do for a very long time.

lesuther wrote: How well have people's field overhauls lasted compared to a total rebuild? I know a guy who got almost 3000 hours on his 470-R, from just a field overhaul and a top end at 1600 from his mechanic, and another guy who had a lower end failure at 600 hours from a reputable exchange....

Lots of times you're paying for the name brand shop, not the build quality. Look at it this way....Joe Blow A&P is working for Western Skyways (or whoever) overhauling engines. He decides to hang out his own shingle and opens a shop doing (guess what) engine overhauls. It's the same guy doing the work....which shop provides a better product? Same deal with a factory reman....that's even more of a crap shoot, a big operation like Lycoming or Continental is just as likely (or more so) to have some rumdums working for them as your small local shop.
I had an eye-opener a number of years ago. I was referred to an engine shop in Oroville WA (Flying Colors) which had OH'd a number of engines for the flying service on my airport. They all went to TBO (and sometimes beyond) with few problems. I hauled my C-145 over there and discovered that Flying Colors Aviation was one guy, Jessie Clark, with a CRS license and a funky little hangar. Jessie did a great job on that engine though, I put 1100 trouble-free hours on it and as far as I know it's still going strong.