L

Loman

Well Known Member
I have come across a used O-320 engine for sale and I am interested in it for my RV-9 build. I can't see how I can ever afford a new or factory re-built engine and it is very tempting to get an engine that works at a reasonable price.

I am very new to aviation so I really don't have the knowledge to assess this properly. I would appreciate any advice that you guys have to offer.

I know from independent sources that this is a good and reliable unit, which has given 7 years of great service on a Lancair and is now being swapped out due to an upgrade to a 200hp engine. The engine is an O-320 A model. I don't have the full designation and I suspect that may not be very relevant for an engine of its age that has been changed a lot. It is a NARROWDECK of 150hp with a low compression set-up. It is fitted with Lightspeed ignition. Unusually, the mount is a Dynafocal. The bottom end was completely rebuild 600 hours ago and the heads were reworked 450 hours ago. In both cases the machining was outsourced and the owner rebuilt the engine himself. A new carb was added 450 hours ago. There is currently a slow oil leak which is probably the main seal. I doubt that there is a complete log available.

From reading previous posts on narrowdeck O-320s, I see there are different opinions on parts availability and cost, conical mounts seem to be a problem and there is a lot of discussion about hold-down plates. This issue seems mainly to relate to conversions to a high-compression 160hp set-up in which I have no interest. Apparently,these engines are lighter, which does interest me.

Included is an exhaust (to suit a Lancair), carb, baffling and oil pre-heater. The price is $8k. Other posters have said that narrowdeck O-320 cores should go for about $5K but maybe the extras make up for this.

Am I crazy to be thinking of this? What factors should I consider?
 
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This engine should be fine for the RV-9. As far as price goes, if you are happy and the seller is happy, that's all that counts.
Actually a good used engine is best for a new airplane. A new airplane needs a totally different flight regime than a new engine. A new engine needs to be run hard for the first few hours. That's NOT what a new airplane needs!
I wouldn't count on the exhaust system fitting the RV.
 
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The narrow deck cylinders cost about $100 more a piece when overhaul time comes around (not a huge factor). Since the engine is older, you might have to deal with more fatigue issues down the road. Other than that, it sounds like a pretty good deal. $8K for a mid time engine (what you describe) seems reasonable to me.
 
What Mel and Stephen said.

You're left with 1400 hours or more....that's 15 years of flying for most folks!

Considering that it's a running engine means that it's a known quantity that you can bolt on and go fly....sounds good to me.

Best,
 
I also purchased a mid time 320. It was a B2B (160 hp) with 1200TT and 300 STOH. A few issues I have encountered during my build.

-If you buy a Sam James engine plenum, it won’t fix no matter what anyone says. You have to make it fit.
-If you want to update it to fuel injection in the future, it will be a little more difficult. Most old cylinders don’t have provisions for primer port and fuel injection. They only have provisions for primer ports. Also the brackets for the spider won’t fit.
-If you want to update the oil sump, you will have to buy additional parts for oil pick up, screen, etc..
-Vans Baffles did not fit quiet right.
-Check that the engine complies with all SB. I had to remove a couple of parts from my oil filter assembly.

I got a few others but they were self inflicted due to my own mods. Hope that helps.

By the way I paid $5,500 and it came (out of an RV-4) with everything necessary to drop it into my RV-4 if I wanted to do so (carb, mags, pipes, prop, prop extension, oil cooler, baffles, etc..). I choose not to.
 
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I wouldn't afraid of the term 'narrow deck'

the newer engine is 'wide deck'

the differences are small.

Look at the base of the cylinders. If its just studs with nuts, its wide deck. If it has a piece of metal or bracket between studs on the same cylinder, then its 'narrow'

The actual base of he cylinders is alittle bit different.
 
narrow deck

The older engines are likely to have lightening holes in the crank flange. I would not want to do acro with a metal prop with the lightening hole flange. Mild acro with a wood prop should be ok.
 
case fretting?

I don't know if this applied to the narrow deck 320, but on my narrow deck 360 when it was orginally made, they didn't put enough dowel pins between the two case halves which could lead to case fretting. My engine was made in the 60's and either at the last overhaul which was 94' or before that, more dowel pins were machined into the case. Might be worth looking in to.

Randy
8A inspection done
 
Buyer Beware

A used engine is a mystery, period. Unless you put all the hours on it over the years, and you supervised all the maintenance, then you really have NO idea what this engine is. Logbooks must be considered pure fantasy! The only way to determine what you have there is to completely disassemble the engine and have all the components tested and checked by a competent shop.

If the engine is cheap enough, and you can handle a possible expensive disappointment, then proceed.

I know engines are expensive, but the engine is the heart of your new airplane. You will be trusting your safety, and that of your passenger to that engine. Ask yourself this question: Would you buy a bran new car with a used engine?

I recommend that you consider building one of ECI's 0320 kit engines made from new TSO parts. The difference in the long term cost might surprise you!
 
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Danny King said:
A used engine is a mystery, period. !
Click to expand...

I bought a B2B that was running and attached to an airplane. I saw it run. I had a friend who is an A&P look at it. I have yet to fly it but it saved me a ton of dough.

What difference would it have made if I had bought that engine AND the plane it was attached to? I certainly wouldn't feel compelled to throw that used "mysterious" engine away for a brand new engine. The plane I owned before building an RV was a 1951 Aeronca Sedan with a 1951 prop and engine and it gave me 6 years of great fun.

So yea, there is a risk but a smaller risk than buying a used engine AND a used airplane too which is done all the time. This was the only way for me to get into the air with my budget. Now, if I were wealthy, no question, brand new all the way.

True, we don't buy a new car and slap a used engine on it but after all the battle scars my "new" plane has on it already, it could be considered used by the time I fly. ;)

I'm not sure what conical mount problems you've read about but I've NEVER flown a plane before where I actually knew what kind of engine mounts it had. I just didn't really care. I've read where Dynafocal's are supposed to be smoother than conicals but hey, we're building airplanes, not Cadillacs!

Good luck!
 
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Questions I would ask:

How many engines has the builder overhauled and was this his first? Did he have an A&P help him? Find out for sure the source of that oil leak. Is it from a cracked crankcase?

All that said, I put many hundreds of trouble free hours on a narrow deck O-320. They are great engines in my opinion. I would seriously consider buying this engine since you have independent testimony that it is a good engine and has proven hours on it, and given your financial constraints.

Don't count on being able to use the baffles or as other have said... the exhaust. An engine heater you can buy for $120 or even much less if you go with an automotive type pad. So the extras, other than an overhaulable carb probably don't add much to the package value.

If the owner would stand behind the oil leak being just a main seal issue, and if you can verify that the engine hasn't had a prop strike. I would go for it. It will be a gamble. Just go into it as an educated gambler. Know the odds.

Put a light weight prop on it and you'll have a great machine. It's going in a 9 so aerobatics should not be an issue.

Lot's of good advice in this thread, including going with a new engine. If there is no way that is going to happen financially, then go after your dream. Make it happen.

My two cents.
 
bought a narrow deck too

I heard the narrow deck engine might be a little more sturdy than the wide deck but don't know if that is true.

I bought an overhauled and test run narrow deck O-360-A1A for my RV-8. It will be sporting a Rotec TBI instead of a carb though. Can't wait to try it out!
 
The only issue I would have is How long has the engine been out of service. Lycoming and Continental engines go to heck really quick in a short period of time.

I purchased a O-320 from a wreck, not a prop strike. Tore the engine down and a lot of rust in the cylinder bores. Junked the jugs, sent out all the iron and the case. Reassembled per the Lycoming manual. The results absoutley perfect 180 hours and doesn't miss a beat.

John H.
 
My RV-6 is flying behind a 1961 manufactured O-320 B2B that I converted to constant speed prop operation. I rebuilt it to NEW specs with new Superior cylinders before flying it. It has flown over 2,200 hours before replacing the cylinders with new ECI cylinders. Both the Superior and ECI cylinders have ports for fuel injection if you want it. When I purchased cylinders 14 years ago and again 1.5 years ago, there was NO DIFFERENCE in price between wide deck and narrow deck from AEROinstock.com. (they advertise on VAF)

The engine now has over 5,500 hours since new. The case, sump, and accessory case are original according to the logbooks and paperwork that I have.
 
Used is good

There are many benefits, and a few drawbacks. But I think the benefits outweigh the drawbacks, FWIW

Randy
Inspected, first flight soon
 
Dash Nothing...

Low-Man!

I flew an 0-320 "Dash Nada" and Sterba wood prop on my RV4 for 11 years and 1200 hours with splendid results.

Advantages:

1. 15 lb lighter weight than a wide deck.
2. Lower entry cost.
3. Constant speed prop crank.
4. Auto Gas capable. (ran nothing but Mo-gas for 10 years unless on XC)

Disadvantages (minor):

1. "Orphan" status
2. Straight mount is non-standard, requires special order from Van's.
3. No 160HP piston upgrade (case through bolts aren't stressed for higher HP)

I highly recommend the narrow deck, they are a great value and performed well for many years. It never failed me :)

Smokey
HR2
 
Loman,

While I can't speak about parts availability or anything for your engine, I will say that 150 hp is plenty of power for a -9. Especially a tail dragger tipup, like you are building. I had all of a 135 hp in mine and with the Catto climb prop it would jump off the ground and still cruise at 165 mph / 140 knots.

The big question for you will be which engine mount to use. Van's makes a 12" one for the O-235 and O-290 powered RV-9's. The standard mount is only 10" long. My O-290-D2 came in at 265 lbs and with the lightweight starter and wood prop, I was almost too light on the nose.

If you are going to run a metal prop or are ever going to run a metal prop, go with the 10" mount. If you are always going to run a wood prop, you can probably get away with the 12" mount. (Van's also sells longer cowls to fit the longer mounts.) Should you run the shorter mount and a wood prop and find you are tail heavy, Saber sells a steal crush plate you can put on the front of your wood prop to move the CG forward.
 
Great replies - Many Thanks

It's time for me to jump back in to thank everybody for their replies. Lots of the regular and most respected posters seem to be in favour of the idea, There were plenty of suggestions for questions that I need to ask and almost nobody was dead set against it.

I am still waiting for replies to some of these questions from the owner but I already know that the engine was running well as recently as last week. It is being swapped out right now and may still be on the airframe. Shame that it is too far away for me to go see it.

I had wanted to fit fuel injection but fitting new cylinders to make this happen would probably not be economic and would re-introduce the risk inherent in a newly-rebuilt engine. The mount remains an issue. I am waiting to hear if it needs a Dynafocal I or Dynafocal II mount. My finishing kit just left Vans with a Dynafocal II in it. I also have a SJ Shorty cowl in the same box so I hope I can make that fit.

The oil leak is probably my biggest remaining worry.

Given that I am at least a year away from mounting the engine, my plan would be to strip the accessories and 'pickle' it on arrival.
 
Loman said:
I am waiting to hear if it needs a Dynafocal I or Dynafocal II mount. My finishing kit just left Vans with a Dynafocal II in it.
Click to expand...
It is most likely NOT a Dynafocal II. The only engine I know of that uses that mount is the IO-320-B1A from a Twin Comanche.
 
It might be a connical mount. Not really a big deal, just spend the money and get Lord monts, regardless of the type of mount.

FYI - you can put fuel injectors in the primmer ports. Check with Don at Air Flow Performance. Fitting a MFP might be an issue but if you go FP, you won't need it.

PS. Regarding my O-290-D2 engine. Not only did I have a 9 pound Catto wood prop but I also had the small Sky-Tec starter, dual P-mags,with Van's 60 amp alt. The starter and P-mags are light and helped keep the weight down. That and the dual EI increases power, 6% I've been told by a well known engine shop. So I was light and had some extra power.
 
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Logbooks??

Danny King is right on the money. Logbooks for an engine are totally worthless when trying to establish the value of a used engine. If it's sitting in the corner of someones garage or shed, it's a core. If it's been sitting around unpickled for a couple of years, it's a core. If you really don't know how it came to be uncoupled from it's airframe, it's a core. I have seen disappointment way too often.
That being said, if you personally remove it from your Moms flying Cherokee and put it on the nose of your new RV9, that's a different story.
Not trying to be totally negative about used engines, just trying to establish that the presence logbooks are most likely useless when determining what you are buying.

Flame suit on...
Chris
 
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