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Engine choice give current Carb dilemma

MS19087

Well Known Member
Just about to order a new 0-320 for my RV-9A then comes the news about Precision stopping production . . . anyone have an update on this? It seems amazing that the industry used a single source for such a critical component.

Now the question is should I go Fuel Injection? I will need to do some minor rework of my firewall . . . overall carbs are simple, reliable, easy install and my experience shows easier to start - especially when engine is hot. FI can be tricky - at least on the C172 SP (IO-360) that I fly.

Any comments on my choice???
 
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Well, FI isn't the only choice. http://www.ellison-fluid-systems.com/

I've never operated one but they seem to work fine once setup properly. An Ellison appears to be a more direct replacement option for a carb. I tend to believe that carb production will resume after a few palms are greased and some deals made. There is just too much at stake otherwise. I sure hope so, or I'll someday be the owner of a 1600 pound Cessna paperweight.:eek:
 
Are parts still going to be available? I know from what little I have read that actual new carburetor prduction will stop but there are plenty of used ones to keep going if parts are available.
 
Was a Carb man but Now got to say FI all the way

Just about to order a new 0-320 for my RV-9A then comes the news about Precision stopping production . . . anyone have an update on this? It seems amazing that the industry used a single source for such a critical component.

Now the question is should I go Fuel Injection? I will need to do some minor rework of my firewall . . . overall carbs are simple, reliable, easy install and my experience shows easier to start - especially when engine is hot. FI can be tricky - at least on the C172 SP (IO-360) that I fly.

Any comments on my choice???
My advice is towards Experimental aircraft, but for a Cessna or Piper, switching from carb to FI will be tricky or impossible from a legal standpoint, at least at this time. You will need some approved STC and approved FI system to convert. Its a moot point for factory planes, you have to dance with the one you got. Switching from Carb to FI on a Cessna, even if it's an option in the future, will be expensive. AFP FI and Ellison TB's are out of course, they are experimental. As was said above parts are available at this time. May be stock up on some spares. However crabs rarely need parts or maintence between overhauls.


It's too soon for existing carb drivers to panic. There are existing stocks of parts out there, plus PMA approved Carb parts from Kelly aerospace. BTW, The hot start issue is no reason to avoid FI. If you use the right technique you can overcome that. Some FI systems have a purge valve which runs the hot gas and vapor out before start.

For RV's
I'm a carb guy all the way, but FI is "better" and in production with three manufactures: Precision, AFP and ECI, a fourth if you include Aerosance's FADEC. I'd stick to the first two, Precision or AFP. ECI's FI is not cheap and its a RPM based system verses a mass airflow FI system. FADEC is a whole different animal and expensive. Frankly I would probably go with AFP now, verses Precision. Who knows when Precision will fold the FI line. I heard Precision was paying over 5 million for insurance on a 4 million dollar Carb product line business. Math is not hard. No way to make money.

On the other hand AFP is a little company, which probably does not have liability insurance. One lawsuit, it might be over for them. May be we should buy from Precision to keep them in business? AFP is only for experimental aircraft and does not have the legacy liability of many 1000's of GA planes flying with their product like Precision does.

I hate to say it, no panic or fear, it looks like if you have a choice today, go FI.

Carb prices where much cheaper than FI, but over the last few years the price of Carbs became on par with FI (to pay for the lawsuits and insurance). FI was always more expensive, but now the price difference is not great. It may be moot if you can't get a new Carb or even a rebuild outright in the near future. Rebuilds outright are available now, from Kellly. Who knows for how long. Precision may still have some reserve stock in the pipeline.

Carb parts will be available for a while. My feeling is support will be around for some time. Someone might buy the rights to make PMA (parts manufacturing authority) of Carb parts, besides Kelly Aerospace.

With gas prices high, FI can save a few percent in fuel burn, especially if you balance injectors and lean judiciously. If you don't throttle back and move the red knob, it does not matter what you have, you'll burn more fuel.

Ellison Throttle Body - They have been around for awhile. They are experimental only, so they don't have the same "liability overhead" as Precision. Over the years Ellison TB's have proved to have a few idiosyncrasy's. The biggest issue I recall are the fine holes in the spray bar. Fuel filtering is critical. Also its more sensitive to air flow into the throat of the TB, verses a carb Venturi or FI TB. On the plus side the Ellison is more ice proof than a carb; however carb ice in a RV is not as a big issue as some airplanes, unless you decide to do long low power descents in pro carb ice conditions, high humidity, temps from 30F to 90F. RV carb ice can happen, just that its not super prone to it, like some Carb'ed Continentals in C182's.

Existing Carb Users
Precision pulled out of the market because of their inability to get product liability insurance. I think it was also a business choice and a Big-Foo-U to aviation and the legal world. After their lawsuit losses, they just said screw it. I wounder if they will stay in business at all. I feel sorry for the employees since many no doubt have been laid off.

It seems like the cards are stacked against Carbs. If you are starting from scratch or buying a NEW engine, FI sure looks like the obvious choice to me, even as a Carb fan. :( If you bought a running engine or have a Carb now, go for it and use it. There will be parts for sometime to come (I hope). You might want to buy some spare parts today?

I don't think Kelly Aerospace makes the carb bodies? So its likely totally new assemblies will be extinct soon, but maintaining existing ones will continue for a while. I'm sure rebuilds will be available for some time. I hope Kelly does not get out of the business. As long as they can insulate them self from the legacy liability of Marvel Schibler / Precision, you would think as the only game in town they would stay in the Carb part business. They look like they will be the only provider of Carb parts when the Precision parts dry up. At this time Kelly sells total "out-right" rebuilds, w/ no exchange. They are available at this time. I'm sure they are checking them twice and making sure they are safe. If you don't own a carb now and want a carb, better get with Spruce or Aviall soon and buy one while you can.

Who knows what the future will hold. Precision, in their good bye letter, said Carbs have been around for a long time and shown to be very reliable. That is true, but accidents happen and people (and lawyers) today want to make it all right with lawsuits, even if the plaintiff is in part or whole to blame for their fate. Yea the carb failed but no one made the plane stall but the pilot. Sure there is cause and effect, but lawsuits have become a pseudo WINNING LOTTO. If you can't win the Lotto, may be you can sue your way to riches.
 
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Switch from carb to f.i. at FWF stage?

I've been wondering why I have been delaying ordering my engine. At first I thought it because I didn't want to part with the money:eek:. However, maybe fate is stepping in to tell me to rethink my carb vs. f.i. choice. All that said, here's my question:

I already have the finish kit for an 0-320 carb, but have done very little work FWF. What would it take, at this point, to switch to fuel injection? My thinking:

1. New lower cowl half if I want to get rid of the cowl scoop.

2. High pressure fuel pump to replace my boost pump.

3. Probably new control cables of different length.

Is there anything else? Like different electrical system?
 
Ellison Throttle Body - They have been around for awhile. They are experimental only, so they don't have the same "liability overhead" as Precision. Over the years Ellison TB's have proved to have a few idiosyncrasy's. The biggest issue I recall are the fine holes in the spray bar. Fuel filtering is critical. Also its more sensitive to air flow into the throat of the TB, verses a carb Venturi or FI TB. On the plus side the Ellison is more ice proof than a carb; however carb ice in a RV is not as a big issue as some airplanes, unless you decide to do long low power descents in pro carb ice conditions, high humidity, temps from 30F to 90F. RV carb ice can happen, just that its not super prone to it, like some Carb'ed Continentals in C182's.
The Ellison will/shall not run on mogas. I contacted Ellison, and they said that gaskets will wear and the throtle could stick. But I have also (later) heard about people running mogas with no trouble whatsoever. Ellison was my first choice, but I ended up with the large cowl for the -4 so I can use FI. Carbs have usually no problems with mogas. But - ethanol in mogas could upset things.
 
My understanding is that Kelly Aerospace makes overhaul kits for the carbs.
http://www.kellyaerospace.com/fuel.html
So, if you buy a new engine with a carb fitted and you do enough hours to need a carb overhaul then its just a matter of overhauling it with the Kelly Kit and it will be as good as new. It may be difficult buying a new carb in the future, but I can’t see it being a problem in the future if you already own one???? Someone please correct me if I am wrong.

Fin
9A 0-320
 
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FWF Carb to FI

I spoke to Van's today with the same question because it sounds like I am at the same stage as you . . . not too far in to change to FI. The IO-320 would require a new lower cowl (larger) - however they state that in fact it would be the 360 CARB cowl w/ scoop. The IO320 will still need a lower scoop unlike the IO360 which apparently is vented differently. In addition, a high pressure fuel pump kit, but to get to scrap the current fuel pump and gascolator. I have a few more call out and will make a choice in the coming weeks. I always wanted FI, maybe this is fate working its magic!!
 
I really think that all the reasons that people have chosen Carbs or chosen Fuel Injection are still valid - the latest letter from Precision wouldn't make me change my position. The reason I say that is that there is an entire fleet of certified airplanes out there that require support to remain airworthy, and I find it hard to believe that market forces won't find a way to support them. And, in fact, there is nothing at all to stop the makers of Fuel Injection systems from issuing a carbon copy of Precision's letter tomorrow, should they decide that they have the same problem with insurance and acceptability of the risk. I guess that we are at the mercy of these legal forces either way, so I think that point is a wash in my decision-making process.

Of course, I could be wrong, and every carb'ed Lyc, Continental, and Franklin equipped aircraft will soon be a lawn ornament....(but I doubt it).

Paul
 
P.R. Play?

The press release from Precision is a way to focus attention on the liability/insurance issue they are experiencing. You will note that the release says "suspension" of production, not termination. So far it has worked, they now have a lot of people's attention.

Sadly, one of the ways to treat the liability problem is to not have any insurance and minimal assets. If there is nothing to go after, the ambulance chasers will leave you alone. I would not be surprised if Precision sells off the carb operation to a "shell" corporation with no assets and a stack of leases and debt. If you sue them and win, they toss you the keys to the plant and say "by the way the rent is past due." :rolleyes:

John Clark
RV8 N18U "Sunshine"
KSBA
 
Get ready for lawn obstructions

1
I really think that all the reasons that people have chosen Carbs or chosen Fuel Injection are still valid - the latest letter from Precision wouldn't make me change my position. The reason I say that is that there is an entire fleet of certified airplanes out there that require support to remain airworthy, and I find it hard to believe that market forces won't find a way to support them. And, in fact, there is nothing at all to stop the makers of Fuel Injection systems from issuing a carbon copy of Precision's letter tomorrow, should they decide that they have the same problem with insurance and acceptability of the risk. I guess that we are at the mercy of these legal forces either way, so I think that point is a wash in my decision-making process.

Of course, I could be wrong, and every carb'ed Lyc, Continental, and Franklin equipped aircraft will soon be a lawn ornament....(but I doubt it).

Paul

Paul, Unless we see REAL tort reform and soon we WILL have parts problems. Remember that Cessna stopped building new aircraft for a while until there was a first round off lawer rip-off protection. The market for aviation parts is so small that if they were sold at a auto-parts store they would discontinue the item due to lack of interest!
We are a miniscule segment of the market, get used to it! This will happen to more and more companies unless there are bills at the national level to stop it. I don't like to be depressing but in this case it's true. hard to take when it is about something you love, but it is still true.
Bill Jepson
 
I spoke to Van's today with the same question because it sounds like I am at the same stage as you . . . not too far in to change to FI. The IO-320 would require a new lower cowl (larger) - however they state that in fact it would be the 360 CARB cowl w/ scoop. The IO320 will still need a lower scoop unlike the IO360 which apparently is vented differently. In addition, a high pressure fuel pump kit, but to get to scrap the current fuel pump and gascolator. I have a few more call out and will make a choice in the coming weeks. I always wanted FI, maybe this is fate working its magic!!

FI is vented differently if you use horizontal induction. If you use updraft induction it plumbs pretty much like a carb.
 
Just buy some spares

Personally, I'd just buy some spares. Precision going out of business still wouldn't be enough to make me put FI on my plane. With a couple of gaskets, a spare float and seat, and a spare accelerator pump you could easily keep a carb running for 15 years.
 
320 carb on 7 and 9

Hi Folks
Just a note about clearance issues I ran into. MA4-5 carb will work on a 320, but will not clear the cowling without major renovation. You will need the MA4short version carb to clear. I am unsure about cowl options available from vans to address this issue, but the bottom line is, make sure you have the right stuff before you fit the cowl. My Superior 0-320 came with the long carb, and they were great about excanging it.
Regards...Chris
 
Hi Folks
Just a note about clearance issues I ran into. MA4-5 carb will work on a 320, but will not clear the cowling without major renovation. You will need the MA4short version carb to clear. I am unsure about cowl options available from vans to address this issue, but the bottom line is, make sure you have the right stuff before you fit the cowl. My Superior 0-320 came with the long carb, and they were great about excanging it.
Regards...Chris

Someone will probably pick up carb production, or we'll see a blanket STC for FI systems. Only so long until supply runs thin. Fortunietly we have factory new precision MA4-5 on the Cardinal, so I don't have to worry about certified problems for a few years. RV will be getting AFP.
 
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