It happened again...

[Jay Honeck]

We've now taken two RV-8As all the way through to the last steps of the buying process, only to have the aircraft fail one (or more) of the prebuy inspections.

The first one had a fine engine, but with cooling problems and flight characteristics that indicated something amiss with the airframe.

Yesterday, we looked at one that was absolutely pristine, and flew like a dream, but failed the engine tests. With just 500 hours it has extremely low compressions, indicating burnt valves and/or other problems.

So, the search continues. I now see that buying a homebuilt is a much more complex task than buying a certificated plane.

 

[wabower]

Most certified planes start their lives with new engines, and unless they have been wrecked the engines probably haven't either.

We've now taken two RV-8As all the way through to the last steps of the buying process, only to have the aircraft fail one (or more) of the prebuy inspections.

The first one had a fine engine, but with cooling problems and flight characteristics that indicated something amiss with the airframe.

Yesterday, we looked at one that was absolutely pristine, and flew like a dream, but failed the engine tests. With just 500 hours it has extremely low compressions, indicating burnt valves and/or other problems.

So, the search continues. I now see that buying a homebuilt is a much more complex task than buying a certificated plane.

 

[Jay Honeck]

Just one example of added complexity:

When buying a certificated plane, I never felt the need to hire an expert who had worked on the line, assembling Pipers. We just presumed they were built correctly.

With homebuilts, I have to hire a guy who has built them, so he can assess build quality. It's just another layer added to an already complex process.

 

[tsts4]

Hmmm - not sure I follow your example. RV's are pretty plain vanilla in materials and contruction techniques. I'm the home stretch of completing my own RV and there's nothing about an RV's contruction that any competent A&P couldn't look at it and pass judgement on during a pre-buy. Having said that, an RV "expert" couldn't hurt (particularly one with expericnce with any mods (like an auto conversion) the builder went with), but the same thing is done in the standard certifed world where buyers seek out folks that specialize in a particular model for pre-buy assistance.

 

[wabower]

The Sport Pilot experts seem to think that the systems rather than the basic build are the most problematic, with engine and fuel problems topping the list.

I'd want an RV guy looking at that stuff too.

Hmmm - not sure I follow your example. RV's are pretty plain vanilla in materials and contruction techniques. I'm the home stretch of completing my own RV and there's nothing about an RV's contruction that any competent A&P couldn't look at it and pass judgement on during a pre-buy. Having said that, an RV "expert" couldn't hurt (particularly one with expericnce with any mods (like an auto conversion) the builder went with), but the same thing is done in the standard certifed world where buyers seek out folks that specialize in a particular model for pre-buy assistance.

 

[tsts4]

Not saying it's a bad idea. I'm saying it's no different than having a Mooney expert look over a prospective Mooney buy. So I'm failing to see the added complexity added to the purchase of an RV-8 (which with fixed gear and if equipped with the standard O/IO 360 is pretty straight forward system wise) as described by the OP.

 

[wabower]

Mooney made most of them the same. That can't be said for the RV builders. The experts in every make/model know about much of the stuff (as well as some of the problems that have resulted) that the other guys don't see on a regular basis.

Not saying it's a bad idea. I'm saying it's no different than having a Mooney expert look over a prospective Mooney buy. So I'm failing to see the added complexity added to the purchase of an RV-8 (which with fixed gear and if equipped with the standard O/IO 360 is pretty straight forward system wise) as described by the OP.

 

[tsts4]

True to a point. However, at least in the case of RV's, the basic airframe and, if a Lycoming is used, the engine doesn't really require "RV" expertize to evaluate. If it does, then I'd pass to begin with unless I knew the builder. In RV's, the number 1 area for variation is avionics, followed by engine mods (electrionic ignition, Fuel injection systems, auto conversations, etc). In those cases, it would be hard to find a true expert because of the shear variety in potenial combinations of components.

Again, I see no difference from the buyers perspective of added complexity to the buy in having an RV guy look at the plane than having a Mooney guy look at a Mooney.

The complexity, IMO, comes from the shear variety of choices, since as you implied, really no 2 are exaclty alike.

 

[Bob Noel]

We've now taken two RV-8As all the way through to the last steps of the buying process, only to have the aircraft fail one (or more) of the prebuy inspections.

The first one had a fine engine, but with cooling problems and flight characteristics that indicated something amiss with the airframe.

Yesterday, we looked at one that was absolutely pristine, and flew like a dream, but failed the engine tests. With just 500 hours it has extremely low compressions, indicating burnt valves and/or other problems.

So, the search continues. I now see that buying a homebuilt is a much more complex task than buying a certificated plane.

maybe this is a dumb question, but what would be the problem with buying the airplane and replacing the engine (appropriately priced)?

Isn't the hardest thing to get a good airframe?

 

[wabower]

I don't either, but you changed your story from "any A&P" to "a Mooney guy" A&P. I'll buy the latter but not the former.

True to a point. However, at least in the case of RV's, the basic airframe and, if a Lycoming is used, the engine doesn't really require "RV" expertize to evaluate. If it does, then I'd pass to begin with unless I knew the builder. In RV's, the number 1 area for variation is avionics, followed by engine mods (electrionic ignition, Fuel injection systems, auto conversations, etc). In those cases, it would behard to find a true expert because of the shear variety in potetnial combinations of components.

Again, I see no difference from the buyers perspective of added complexcity to the buy in having an RV guy look at the plane than having a Mooney guy look at a Mooney.

 

[tsts4]

I don't either, but you changed your story from "any A&P" to "a Mooney guy" A&P. I'll buy the latter but not the former.

Not exactly-- I was using the seperate lines of reasoning to point out that for RV's, the pre-buy inspection didn't necessarily add complexity to the purchase. Both Mooney's and RVs get sold every day both with and without "expert" assitance with inspections. Using a expert to help with the purchase of an E-AB adds no more complexity to the buy than using one in the standard certified world.

The complexity lies in evaluating what's hanging on the airframe which can and does vary wildly from E-ABs of the same make and model. But based upon the OP's limited description of the issues with these particular RV-8As, I assumed perhaps erronously, that the issues were more fundemental and could have been evaluated without the assistance of a so called "expert".

 

[Chip Sylverne]

How about a counter offer discounting by the price of 4 new jugs? Pristine airframes are hard to come by....

 

[steingar]

Something to which I have eluded over and over, to the disdain of the Ex/Ab community. There are extra issues involved in purchasing a homebuilt aircraft. Just because you assembled your kit properly doesn't mean the guy across the way did likewise. Thus extra layers of complexity, and the main reason I counsel new owners away from experimentals.

 

[CJones]

Something to which I have eluded over and over, to the disdain of the Ex/Ab community. There are extra issues involved in purchasing a homebuilt aircraft. Just because you assembled your kit properly doesn't mean the guy across the way did likewise. Thus extra layers of complexity, and the main reason I counsel new owners away from experimentals.

My bro-in-law used to work for a law firm that was counsel for one of the major aircraft manufacturers.

I was at a holiday party at his house once and I got on the topic of flying with a group of folks. I ended up telling them about how my dad and I built an airplane in the basement/garage. They said they typical "Oh my. And you feel like you can build an airplane safe enough to fly in!?" My b-i-l broke into the conversation and said "I have seen and dealt with the people that put together the 'real' airplanes. I definitely trust him (me) more than I trust those guys!".

I'm not sure why people continually think that the only people that can pound rivets are the $15/hr assembly line workers at the spam-can factories.

 

[JHW]

Just one example of added complexity:

When buying a certificated plane, I never felt the need to hire an expert who had worked on the line, assembling Pipers. We just presumed they were built correctly.

With homebuilts, I have to hire a guy who has built them, so he can assess build quality. It's just another layer added to an already complex process.

Bad assumption. What you've described relates to buying any airplane. After 3-5 decades of various repairs, documented and otherwise, a used factory-built is just as suspect as a used RV, probably more so due to age and corrosion concerns. When I was shopping travel airs I bought he 13th one I inspected.

 

[Jaybird180]

How about a counter offer discounting by the price of 4 new jugs? Pristine airframes are hard to come by....

My thoughts

 

[wsuffa]

Bad assumption. What you've described relates to buying any airplane. After 3-5 decades of various repairs, documented and otherwise, a used factory-built is just as suspect as a used RV, probably more so due to age and corrosion concerns. When I was shopping travel airs I bought he 13th one I inspected.

Exactly my view, too. Based on experience.

 

[docmirror]

If everything else checked out, ask the seller to split the cost of four O-hauled jugs and replacement. That's not a hard job provided the RV-8 has room to pull the jugs without engine removal. Top o-haul in place, test, fly.

 

[Chip Sylverne]

If everything else checked out, ask the seller to split the cost of four O-hauled jugs and replacement. That's not a hard job provided the RV-8 has room to pull the jugs without engine removal. Top o-haul in place, test, fly.

The cost delta between o-hauled and new isn't that great. I cheaped out when I had to top an 0-320. Lasted 400 or so hours before there was cracking in the exhaust ports. False economy.

Go new.

 

[docmirror]

The cost delta between o-hauled and new isn't that great. I cheaped out when I had to top an 0-320. Lasted 400 or so hours before there was cracking in the exhaust ports. False economy.

Go new.

I have no expertise in the Lyc engine cylinders. However, your experience does not sound common in the market. If it were, we would be hearing a great hue and cry about crappy Lyc o-haul jugs just as we heard a few years back about Conti jugs(that really were crap). The fact that you had a 100% failure rate does not point to a pandemic with the rest of the market.

 

[Velocity173]

Just one example of added complexity:

When buying a certificated plane, I never felt the need to hire an expert who had worked on the line, assembling Pipers. We just presumed they were built correctly.

With homebuilts, I have to hire a guy who has built them, so he can assess build quality. It's just another layer added to an already complex process.

Jay your problems have nothing to do with homebuilts or the RV series. You could have the same problems with a certified. It's not like the engine is some auto conversion. These are Lycomings, and the problems would be the same as on a certified. If anything they've been run cooler with the faster climb out speeds. As far as the airframe, any guy with RV experience will be able to tell if it was built straight and the controls balanced properly. If it's not, keep looking.

I'd much rather have a 10 yr old airframe that's stressed to accept aerobatic loads than a 40 yr old one that isn't. You'll find one out there and I know you won't regret it. Besides a Glasair they're the perfect 2 place hauler.

 

[Chip Sylverne]

I have no expertise in the Lyc engine cylinders. However, your experience does not sound common in the market. If it were, we would be hearing a great hue and cry about crappy Lyc o-haul jugs just as we heard a few years back about Conti jugs(that really were crap). The fact that you had a 100% failure rate does not point to a pandemic with the rest of the market.

Wasn't 100% failure rate, it was 50% on two different occasions. Ended up with 4 new at the end of the day. The labor alone would have paid for 4 new cylinders the first time. The price of new vs overhaul, provide the jugs in good enough shape, is roughly what, $2k? To me, not much, in the scheme of things. YMMV.

 

[docmirror]

Wasn't 100% failure rate, it was 50% on two different occasions. Ended up with 4 new at the end of the day. The labor alone would have paid for 4 new cylinders the first time. The price of new vs overhaul, provide the jugs in good enough shape, is roughly what, $2k? To me, not much, in the scheme of things. YMMV.

I'm sorry you had such trouble, but again the failure rate in your situation doesn't seem to represent the entire market. I would put your experience in the lower percentile of the rest of the o-haul jug market. Unless we hear from a lot of owners out there complaining about Lyc jugs, I'm not buying new is better by the cost differential of the labor to replace, but like I said, you have more experience, I just think your data point is an artifact.

 

[RogerT]

Not everyone should own an Exp/AB. It takes someone who's mechanically
inclined, has a reasonable understanding of the systems involved and who is willing to spend the time keeping it up. Not everyone is going to be comfortable in that arena. The fact that you can do all the maintenance yourself is great .. if you have the knowledge to do it.
I've been in the Exp/AB class for about 8 years, starting with my first build,
then a Sonex I didn't build .. and now the Sonex I just finished and am flying off
the Phase 1. I can't imagine going back to TC'd aircraft .. but it's an individual thing.

RT

 

[airguy]

Jay - The Force is telling you that you need to build one....

 

[weirdjim]

Yesterday, we looked at one that was absolutely pristine, and flew like a dream, but failed the engine tests. With just 500 hours it has extremely low compressions, indicating burnt valves and/or other problems.

So, the search continues. I now see that buying a homebuilt is a much more complex task than buying a certificated plane.

So you have an aversion to getting greasy pulling four easy jugs and doing a field top? Whassa matta? You too smart a guy to turn down a pristine airframe for eight poopy valves. Lycomings come apart real easy like.

Could probably finish a field top during Oshkosh week if we had the tools right there and handy.

Jim

 

[kyleb]

We've now taken two RV-8As all the way through to the last steps of the buying process, only to have the aircraft fail one (or more) of the prebuy inspections.

The first one had a fine engine, but with cooling problems and flight characteristics that indicated something amiss with the airframe.

Yesterday, we looked at one that was absolutely pristine, and flew like a dream, but failed the engine tests. With just 500 hours it has extremely low compressions, indicating burnt valves and/or other problems.

So, the search continues. I now see that buying a homebuilt is a much more complex task than buying a certificated plane.

You're making the process hard.

99% of the airplanes in the fleet would require something to bring them up to the next owner's standards, so if you find an airplane that is close, you negotiate the price to reflect the expense of the repair(s) or upgrades and close the deal.

If you wait for the perfect airplane, you might wait for a long time, and/or you might not ever find one.

 

[Jay Honeck]

maybe this is a dumb question, but what would be the problem with buying the airplane and replacing the engine (appropriately priced)?

Isn't the hardest thing to get a good airframe?

And we are considering doing exactly that. It's what we did with our Pathfinder, actually, when we bought it in 2002.

On the flip side, it's usually MUCH cheaper to simply buy one with a good engine in the first place.

 

[Skylane81E]

So you have an aversion to getting greasy pulling four easy jugs and doing a field top? Whassa matta? You too smart a guy to turn down a pristine airframe for eight poopy valves. Lycomings come apart real easy like.

Could probably finish a field top during Oshkosh week if we had the tools right there and handy.

Jim

You'd need a week?!

:wink2:

 

[Geico266]

And we are considering doing exactly that. It's what we did with our Pathfinder, actually, when we bought it in 2002.

On the flip side, it's usually MUCH cheaper to simply buy one with a good engine in the first place.

Jay, what is the engines history?

What are the compression?

 

[Jay Honeck]

I have no expertise in the Lyc engine cylinders. However, your experience does not sound common in the market. If it were, we would be hearing a great hue and cry about crappy Lyc o-haul jugs just as we heard a few years back about Conti jugs(that really were crap). The fact that you had a 100% failure rate does not point to a pandemic with the rest of the market.

I don't know any A&P mechanic that doesn't back up Chip's assertion. The difference in cost between new and overhauled cylinders is insignificant, and the performance advantage is clear. Go new, every time.

The seller's engine was overhauled just 500 hours ago. The builder went cheap, and used overhauled old cylinders. The worst was 36/80. The second worst was 52/80. Total crap, in just 500 hours. He made a bad choice.

 

[Skylane81E]

I don't know any A&P mechanic that doesn't back up Chip's assertion. The difference in cost between new and overhauled cylinders is insignificant, and the performance advantage is clear. Go new, every time.

The seller's engine was overhauled just 500 hours ago. The builder went cheap, and used overhauled old cylinders. The worst was 36/80. The second worst was 52/80. Total crap, in just 500 hours. He made a bad choice.

I don't mind doing rings, but when you factor in warranties on new cylinders it isn't a bad place to spend a little extra money.

 

[Jay Honeck]

Jay, what is the engines history?

What are the compression?

36/52/60/62. Unacceptable.

Here's the deal: The plane in question has a fixed pitch Catto prop. This means that to keep up with constant speed prop-equipped RVs, the seller had to wind the RPMs out to 2600+ RPMs. Put that together with a wee bit of over-leaning, and you've got the perfect recipe for burnt valves, and ruined compressions.

Since the seller flew formation for fun with other RVs (he's a retired F-16 jock, and a totally great guy), this explains why a perfectly good Lycoming O-360 had horrible compressions after just 500 hours.

Yes, the fixed pitch prop planes are nearly as fast, but to achieve those similar speeds means winding the engine up to much higher -- and louder -- RPMs. I think our rejected low compression RV-8A is an example of what these excessive RPMs can do.

Upon further reflection, we've now decided that a constant speed prop is a prerequisite in any RV-8A. Mary had already noted that this particular plane was MUCH louder than the CS prop-equipped RV-8 we had flown last month. Since it runs several hundred RPMs faster than a similar constant speed prop equipped RV, this isn't surprising.

Our search is now restricted to only RV-8As with CS props.

 

[kyleb]

Jay, your first conclusion was that remanufactured cylinders were the problem. Then you concluded that running the engine at 2600 rpm's was abusive and was the problem and because of that, you're gonna set your requirements to C/S only.

Basing big conclusions on a sample size of one may not be your best approach.

And then we have the conclusion that buying a homebuilt is more complex than buying a factory built.

I'm starting to think you're looking for a reason to not buy an airplane, as opposed to looking for a reasonable deal, then making that airplane yours...

 

[Jay Honeck]

Jay, your first conclusion was that remanufactured cylinders were the problem. Then you concluded that running the engine at 2600 rpm's was abusive and was the problem and because of that, you're gonna set your requirements to C/S only.

Basing big conclusions on a sample size of one may not be your best approach.

And then we have the conclusion that buying a homebuilt is more complex than buying a factory built.

I'm starting to think you're looking for a reason to not buy an airplane, as opposed to looking for a reasonable deal, then making that airplane yours...

Lol! In a buyer's market, prebuys are, by design, a grueling elimination game. There is no need to accept anything less than perfection right now, and I am in no hurry.

My reasoning behind the constant speed prop decision was edited for brevity, but the two major reasons stand. Noise in the cockpit is much higher with a fixed pitch prop, unless you dial the power back -- which results in speeds in the 140 knot range.

Since my current ride is already a 140 knot aircraft, this would leave me with a bad choice of, essentially, go fast or go quiet.

One goal in buying an RV is to be able to get back to Iowa in significantly less time. The thought of enduring those high RPM noise levels to/from Iowa (or OSH) is a bad one, and led us to the elimination of any plane with a fixed pitch prop in our search.

WRT the burnt valves, that was pure speculation, suggested in another group I'm in. It makes perfect sense, however, given the seller's mission of formation flying, which requires high RPMs/power (to keep up with the CS equipped RVs), and constant power changes to maintain position.

This is not the kind of flying where engine management is your primary concern. A little too lean, and you're gonna cook those valves.

This seems like a logical explanation for having three bad cylinders on a bulletproof O-360 in just 500 hours. And the "good" one had compression in the low 60s, so it's not long for this world, either.

The other possibility was a crappy engine rebuild. We know the original builder "went cheap" and rebuilt the old cylinders. In my opinion -- and the opinion of every A&P I know -- that's false economy.

Either way, for whatever reason, the guy's engine is trashed. Did it take the camshaft with it? If so, you're looking at a very expensive proposition, indeed.

So, we're on to the next ones.

 

[wabower]

L

One goal in buying an RV is to be able to get back to Iowa in significantly less time. The thought of enduring those high RPM noise levels to/from Iowa (or OSH) is a bad one, and led us to the elimination of any plane with a fixed pitch prop in our search.

Really? Fltplan.com seems to think the KRAS-KIOW trip is 30-40 min difference each way. How many trips per year will be necessary to make such a trade feasible? Where you gonna put all that crap you take to OSH?

 

[kyleb]

My reasoning behind the constant speed prop decision was edited for brevity, but the two major reasons stand. Noise in the cockpit is much higher with a fixed pitch prop, unless you dial the power back -- which results in speeds in the 140 knot range.

RV's are louder than the hammers of hell, regardless of RPM. They typically don't have mufflers or enough soundproofing to matter. So c/s prop or not, you're gonna need a good set of active headsets, which makes it a moot issue.

 

[docmirror]

36/52/60/62. Unacceptable.

Here's the deal: The plane in question has a fixed pitch Catto prop. This means that to keep up with constant speed prop-equipped RVs, the seller had to wind the RPMs out to 2600+ RPMs. Put that together with a wee bit of over-leaning, and you've got the perfect recipe for burnt valves, and ruined compressions.

And you're blaming the results on bad o-haul? Or your statement is that a new cylinder would have fared better?

hmmmmmmm, Ooooooooooookkkkkkkkkkkkkkkkk.

 

[Jay Honeck]

Well, now, here is an interesting turn of events.

The seller just called. He was a nanosecond away from ordering four new cylinders, when he decided to double check the compressions with another mechanic.

The first one was 78/80. WTF?

All of them checked out in the upper 70s, on a COLD engine. WTF??

There is NOTHING wrong with this engine. The first mechanic has checked his equipment, and has supposedly found a bad o-ring.

This mechanic very nearly cost the seller $7 - $10K in unneeded engine repairs. And he certainly cost him our sale.

Wow. Just wow. All for the want of a 30 cent o-ring?

If anyone is looking for a great RV-8A with a fixed pitch 2-blade Catto prop, I can vouch for this one. It flies GREAT.

Sent from my Samsung Galaxy S3...

 

[Jay Honeck]

Really? Fltplan.com seems to think the KRAS-KIOW trip is 30-40 min difference each way. How many trips per year will be necessary to make such a trade feasible? Where you gonna put all that crap you take to OSH?

Knowing this day would come, three years ago we bought a 16' trailer that lives in OSH. Inside is our entire "North 40 compound", just waiting for our arrival. We could go to OSH in a Cub, now.

And speed is only one reason for wanting an RV-8A.


Sent from my Samsung Galaxy S3...