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Buying a Used RV7 - Carburetor vs. Fuel Injection

Canadianflyer

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Hello, I am looking for advice on a potential Vans RV-7 purchase. The plane seems to be in good condition, very well built and well maintained.

It is a 2015 model featuring an Aerosport 0-375 engine and it only has 215 hours on it. My concern is around the engine itself being a carburetor model and not fuel injection. I realize it's more things to worry about, a greater chance for icing, and less fuel efficient.

I am wondering if I should hold off for a similar plane with a different engine, see if I could get the engine modified, or if it doesn't make much of a difference.

Thank you very much!
 
Unless you plan to fly sustained inverted aerobatics, I wouldn't disseminate just because of a carb. Of course, that is coming from someone that flies with a carb.
 
Carb vs FI...........

Unless you plan to fly sustained inverted aerobatics, I wouldn't disseminate just because of a carb. Of course, that is coming from someone that flies with a carb.

Agreed. Mine has 1220+ hours on a carb...and many more on the Cub. You can always add a fuel injection later if you just HAVE to have that.
 
I have a non-RV with a carb. That plane has an ARP carburetor ice detector. The light comes on when there's actual ice, and it shows the onset of icing. It's been reliable to the point that my RV-3B project also has a carb and I bought another ARP carburetor ice detector for it.

The device is only available from Aircraft Spruce.

Dave
 
greater chance for icing, and less fuel efficient

Correct.
Of note: been flying my carbed O-360 in ice conductive weather more than once, but never encountered carb ice... standard Van's airbox/filter.
Regarding the ability of leaning, yes, there is a minute difference... getting LOP >20 and the she starts running rough and loose power.

One advantage though, injectors rely on absolute clean fuel. The slightest impurity will clog them, and I know more than one pilot having lost a cylinder due to that. Won't happen with the carbed one...
 
Or, just end the issue and back fit the very nice AirFlow Performance fuel injection system. This is a bolt on replacement - other than you need to replace the mechanical fuel pump with the high pressure version, and replace your low pressure boost pump with a high pressure boost pump.

I installed this system on my first RV (that was before Van’s offered a 180hp IO-360). It now has ~1400 hours and still going strong.

Carl
 
One thing to keep in mind is that a carb equipped airplane will have a much less expensive fuel pump, gascolator, simpler plumbing, and will be lighter.
I have both and for a non-dedicated aerobatic mount a carb is my choice.

For LOP operation a fuel injection is obviously superior.
 
If I was looking to buy an RV, FI vs carb would not be the decision maker. I would prefer injection, but I would first worry about:
- airframe condition
- engine condition
- 360 ci engine, but not a deal breaker, just a cost differentiator
- avionics
- interior
- engine hours
- then FI vs carb

If I found a good carbed one with everything else I wanted, that would be the one.

Tim
 
I had a carb icing encounter with my C-152 years ago and it scared the heck out of me. Took me a couple seconds to figure it out and pull the carb heat knob. We had an Ercoupe on the very same field that didn’t make it and drilled it into the ground climbing out after takeoff, killing the passenger instantly and the pilot succumbing to his injuries several months later.

I have since discovered the joys of flying behind FI with my RV-10 and would not consider a carbed engine in my -9A. A hanger buddy looking for a built -9A to buy is a retired AP/AI and is in the same camp. He’s looking at a -9A for sale right now that is carbed and the first thing he will do if he purchases it is convert it to FI. This subject matter falls under the “Primer Wars” category though, and is subject to opinions only. I would not let the sale fall through though if the price is right. Helping my buddy out, I budgeted him $4000 to do the conversion with a brand new AFP fuel injection kit, new mechanical and electric boost pump filter, and new fuel supply lines from TS Flightlines.

Every so often, someone on the forum will convert their mechanical FI system for full electronic FI and sell their used stuff here at attractive prices.
 
Hello, I am looking for advice on a potential Vans RV-7 purchase. The plane seems to be in good condition, very well built and well maintained.

It is a 2015 model featuring an Aerosport 0-375 engine and it only has 215 hours on it. My concern is around the engine itself being a carburetor model and not fuel injection. I realize it's more things to worry about, a greater chance for icing, and less fuel efficient.

I am wondering if I should hold off for a similar plane with a different engine, see if I could get the engine modified, or if it doesn't make much of a difference.

Thank you very much!

As has been said already, carb would not be a deal breaker for me either. Many other things that need to check out first. I don't think a carb gives you more to worry about, just different things to think about.

RV's do not seem to be prone to carb ice. I have almost 1000 VFR hrs split between a 4 (carbed O-320) and a 7 (carbed O-360) and have never had an issue in the air. I have had carb icing on the ground prior to TO 4 times in the 8 years I have had an RV. My Long-EZ friend has to really watch it as his is very prone to icing. Of the dozen RV's on our field 2/3 are carbed.

As far as fuel efficiency goes...I fly for fun not speed, typically fly leaned out to peak or LOP at 60% power (Skyview display) averaging 6.7 USG/hr (over the 495 hrs in my 7 to date) around 145 kts indicated.
 
Lack of a constant speed prop, not presence/absence of fuel injection, was the deal-breaker for me when I was looking to buy an airplane these days, but I really didn't know what I didn't know. I'd only owned/flown planes with carbs. My plane happened to have FI when I bought it and now I'm very glad it does. Hot starts might occasionally be a little finicky on hot days but I think the advantages are significant compared to the disadvantages. If I was buying a plane again, I'd be inclined to put lack of fuel injection in the negative column.
 
We’ve currently got two injected airplanes, and two with carburetors - all work just fine, and while the injected airplanes get leaner smoother, the carbed ones can be flown LOP without any real problem - we just bring the throttle slightly back off the stop to disturb the flow, and they smooth right out. In the end, I’d say that we can run the FI engines maybe 0.5 gph leaner than the carbed airplanes - but remember that when you do that, you are also giving away speed.

I will add that I am getting to be a sort of old pilot, and have flown an awful lot of different airplanes and engines - some of them really make you hold your mouth just right to get them started, hot or cold. We have no issues starting any of ours cold, and have learned the right techniques that our particular injected engines like when they are hot. But still....if I land for fuel in the middle of absolutely nowhere, with temperatures above 100 degrees and a quick turn for fuel, I kinda like having the carbed engines - they pretty much start every time when hot, while the injected engines sometimes make you work for it.

I absolutely wouldn’t “not buy” an airplane because it has one or the other - its easy to change later if you want.

Just my opinion...
 
Back in the '90s when I was building my plane, it seemed like everyone who had FI had some kind of thing they were always fussing with; hot starting and clogged injectors and balancing and all of that, so I just decided to stick with tried-and-true. I'm sure the technology has improved since then but I have 1500+ hours on my old carb and I've never regretted it. I have a carb heat temp probe and rarely if ever see it close to freezing, never had a carb ice issue (knock on wood).

In fact of the 30-odd planes I've owned, rented or borrowed in 40+ years of flying, I don't think any one of them has had FI. Not really relevant but still.
 
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I have flown both carbs and FI in various different models. Each has slightly different idiosyncrasies that are easy to adapt to and handle. The real only no-go is inverted flight and a carb. The rest of the pros and cons of each system are more personal preference or a minor inconvenience at worst. So if you're not planning sustained inverted flight, don't worry about a carb. It will fly just fine.
 
I've owned a lot of aircraft over the years, many injected and many with carbs.:D
My preference is always fuel injection but like several others have said there are many things far more important than fuel injection so I don't think you should make this your big determining factor.
Whatever you choose I wish you safe and enjoyable flying. Robert
 
Thank you!

Thank you very much for all of the advice everyone. Your input has helped immensely.

It would seem to me that Carb is much less important than I was making it out to be. It may not be as economical in cruise or reliable during aerobatics, but it seems to be reliable in heat and lighter. So two benefits for sure.

I will be taking a closer look at the plane and going from there!

Thank you again.

Kyle
 
In my humble experience Lycomings are not as likely to get carb ice as Continentals because the intakes go through the oil pan on most models. A Continental can ice up pretty easy with a carb.
 
Ice

In my humble experience Lycomings are not as likely to get carb ice as Continentals because the intakes go through the oil pan on most models. A Continental can ice up pretty easy with a carb.

that is exactly correct. Never a hint of ice in my close cowled Tailwind with 0 320 and carb. Very rare to see carb ice in Cherokees and others with Lycoming engines, except in actual airframe icing conditions.
If you like the airplane don't let this be a concern.
 
In my humble experience Lycomings are not as likely to get carb ice as Continentals because the intakes go through the oil pan on most models. A Continental can ice up pretty easy with a carb.
I don’t know what it is, but I think there is some other difference that adds to Continentals’ susceptibility to carb ice. The O-300 in my 170 has the carb bolted to the bottom of the oil sump and the tee to the manifolds cast into the sump, yet is still quite susceptible to carb ice.
 
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