SB for Marvel-Schebler, Facet, Precision, Volare Carburetors

(Did not see this posted on VAF)

SB 518, dates July 18, 2008. Reprint of Precision Airmotive Mandatory Service Buylletin No. MSA-13. Replacement of floats with foam floats.

Yet another service bulletin I will have to investigate:

http://www.lycoming.textron.com/support/publications/service-bulletins/pdfs/SB582.pdf

I read both the original Precision Mandatory SB from 1-08 and the Lycoming release dated 7-08 and now I am really confused.

I have an MA4-5 (4164-1) on my Eci 0360 that was rebuilt by Precision in April of 05. Reading the Lyc bulletin it says that "Models Affected" -- "have been rebuilt or repaired since November 1, 2005." Sounds like mine is not affected since the work was prior to Nov 05--but wait!!

The Precision Bulletin says that the New Improved floats have been in production since November 2005 and that if you don't have one of these new improved floats you need to get one installed by no later than December 2008. Since my carb was rebuilt prior to Nov 05 sounds like I am affected.

These seem to be in conflict with each other---Lyc sounds like those rebuilt since Nov 2005 are affected but Precision sounds like all prior to that date (before the new float was available) are affected.

Comments????? Interpretation?????

My head hurts--I am going for a gin and tonic!

Cheers,

db

mine is affected. ic number is 6......guess i get to call someone monday morning.

IC #15

Just went out and checked my IC # is 15. I am not affected. Not so lucky with the Slick SB's. Both mags are effected. Airplane is not flying yet and I am hoping that Slick will come up with a permanent fix for the mags rather than the repetitive SB before the plane is flying.

Where can I get the new floats?

OK I have an O-320 and my carburetor IC# is 1, therefore I will need to replace the floats. Does anyone have a price and or vendor? Precision sold the MSA line and I can't find a website for Volare.

Thanks in advance for any help.

Don't bother calling Volare... The number Precision gave me is 336-449-4893 which rang to Aero Accessories. The guy who answered the phone was clueless but gave me another number 336-449-5054 (The number on the Lycoming SB) and told me to ask for Kim or Marshia. They to were at Aero Accessories but they would not give me a price and said that all parts must come from a distributor of theirs. AeroAccessories claims to be the maker of Tempest brand stuff. This carb business is a convoluted mess of businesses... AeroAccessories claims to make Tempest brand stuff which created a sub company named Volare who now owns the rights to the Precision/Consolidated/Marvel-Schebler/Facet carb line new manufacturing, parts and service/support or at least that is my understanding of it all.

Here are a few distributors she gave me:
API (which you must apply to be able to buy from)
AVIAL (have not tried yet)
Quality Aircraft Accessories (have requested a quote via email)

I am sure there are other distributors but these are the ones they gave me. http://www.aeroaccessories.com/order.html#northamerica

I have a IC-1 with the metal float which is like new but I was just trying to get a price and availability on the foam float in case I wanted to go ahead and change it. Most likely I will fly with the metal one.

Carburetor

Here is another angle on this subject. Four months ago I bought a OH Marvel 10-4164-1 carburetor from Quality Aircraft Accessories (QAA). When I saw the SB concerning the new type of float I called QAA to ask them if my carburetor needed this upgrade. Apparently my carburetor was OH by Kelly Aerospace Power Systems and the float system they fit to their OH carburetors is not implicated by this SB hence it does not need changing.
Must have been my lucky day!!

Barry RV6A F-PRVM

Yep Kelly has a paper out about this.

http://www.kellyaerospace.com/service_pdf/SL027_brass_float.pdf

The only problem is if you have a metal float and cannot 100% be sure it is a Kelly float, they recommend you change it anyway.

Just keep the metal one unless you start having problems...

Rebuilt carb

My carburetor was purchased from AERO in 2007. The paperwork shows the unit (MA-4SPA) was "overhauled" by Avstar. I just called Avstar to inquire about the SB. The letters and number in the bottom left corner of the red data plate are MF V A1. The letters MF mean a metal float is inside. The metal floats they use are not subject to any issues, such as specified by a Service Bulletin. No action is required with the carburetor I have.

Just thought I'd report my findings.

Just thought I would let everyone that is interested in this SB that Volare is now shipping the new "Foam Filled" floats.

I just replaced mine per the SB.

For a MA4-5, the correct part number is 30-862.

I ordered mine from A.E.R.O. They backordered the float but it showed up in less than a week.

The new float is solid foam and is smurf blue.

You will also need:

1ea 16-A31 Gasket - Throttle Body to Bowl
1ea 82-11 Cotter Pin
6ea 78-A97 Washer - Throttle Body to Bowl Screw

My original was brass but I have heard too many bad stories of floats sinking so I decided to bite the bullet and get it replaced before I am ready to fly. A local RV9 had an engine failure on his way to the Bahamas in his new plane. Brand new Lycoming and a sunk float was the culprit. Lucky for him he found a strip to land on.

Precision SB... Clarification

The reason why that SB and subsequent AD was made, was so customers of Precision Carbs used Precision parts, instead of perfectly good Kelly Brass Floats, which btw are not effected by that stupid SB.
I spoke to people at Precision and they told me... its bs, they simply wanted people to buy their ****, instead of using the brass floats.
Also note, that the old black floats are also foam floats, suceptable to problems because they would soak up with fuel, and open the needle.
At the same time Precision started making "Advanced Polymer" floats, white ones, hollow plastic floats. THEY ARE ****! There is no adjustment to them, something that is available with all brass floats.

anyhow, I just thought to give you some extra info on this, from some of the guys that do this everyday!

here is the Kelly SB regarding the precision sb: http://www.kellyaerospace.com/service_pdf/SL027_A_brass_float.pdf

Yes, most of us are aware of all the history. Problem is...unless you know the exact history of a carb, you have no idea if the brass float is made by Kelly or Precision or anyone else that may make one. If you don't know for sure, Kelly sez change it....

The black foam floats were of a totally different material than the new blue ones and the blue ones are adjustable just like the brass ones are.

Just in case they come out with a SB telling you to change the blue foam one for a brass one, I kept mine safe in the box

If you don't know the history of your carb... you have bigger issues than your floats.

its a bogus, to me.. sb
Precision went out of the Carb Business, officially in October 2007, 15-th I believe. That SB, MSA-13 is dated... December of 08
and why would a company going out of business do that, so as to give the others issues.
Look, brass floats are still as good as they were 15 years ago when the first SB MSA-1 was introduced. Its just plain marketing.
If a person is seriously concidering replacing a brass float with a plastic, because the tab is worn, or there are issues with the float, not the needle, then we can agree that... ok... the float must be replaced cause its not doing what is should be. If however you are John Doe, working on YOUR aircraft, and still don't understand it, there are shops that would gladly pop your carb open, most likely the shop that did the last OH last, change the gasket, retighten the bowl, inspect the float for damage, check it, usually under hot water... standard stuff, and give it back to you. I do that every day.
For homebuilt guys, if you can build an airplane, or pay someone to do that for you, you can get a float kit, from Kelly or whomever and just do what the little pamphlet tells you to do. set your float, get it straight and try it.
Either way, for me... that sb is bogus. The only reason why those floats, the "Smurf" blue floats are being used, is because Precision found that in HA-6 carbs they work... if you can call HA-6 carbs working!

Dude,

Like you said Precision is long gone. My Smurf blue float came from Volare, Precision won't even talk to you about carbs anymore if you call them.

I did change it myself as well, easy to do.

Tell the guy I know with a brand new "certified" engine in his RV9A that sunk the float on the way to the Bahamas that this SB is ****... I think he will argue with you on that.

The float sank?
a) How?
b) If its a NEW Certified engine... why did the carb give out? was it installed wrong?

btw... you do know that Volare/Tempest bought all the stock that Precision made, therefore they will continue to sell Precision stuff until they make some for themselves.

a) it had a hole in it and flooded therefore it sank.
b) have no idea bad float I guess, very low time engine not long after 25 hour phase I.

My smurf blue float had a manufacture date of 09/12/08, guess their out of Precision stock....

Anyway, I don't care....I wanted my carb to be current to the newest standards and therefore at this time it is. Everyone can decide for themselves what they want to do about theirs.

tKolev said:

The float sank?
a) How?
b) If its a NEW Certified engine... why did the carb give out? was it installed wrong?

btw... you do know that Volare/Tempest bought all the stock that Precision made, therefore they will continue to sell Precision stuff until they make some for themselves.

Click to expand...

that really sucks.
That problem, with the brass float, that is an inspection problem, if it wasn't done right... that's what happens!
As far as staying current with carbs... ahhh.... with so many companies selling out, Precision, Unison [selling Slick Mags to Champion], and so many FAA PMA manufacturers... its really hard, to be current to the NEWEST of the NEW.
Instead of looking for the NEWEST stuff on the market, look for something durable.
Here is a perfect example:

Slick Magnetos: excellent design, really nice to work on. BUT the new production models, eg 4309/4310. Those two are horrible. The drive that comes with that particular magneto type is suceptable to cracking, damage, est, ALL Slick 4300 and 6300, have 2 major problem, especially the new ones. The cam and the carbon brush. Recently Slick came out with an SB, that stated that if you've had a recently repaired or NEW magneto, you should be checking the Carbon Brush EVERY 25 hours until 50, every 50 hours until 250, and then if you still have a brush, every 100 until 500, at which point you automatically replace the brush.

There are 2 basic and very simple solutions for those 2 problems. get a new mag every 25 hours or make sure that your mag was well built. I took apart a mag, fresh from the manufacturer, it was so poorly built, that its just not funny any more.

I still don't understand why so many people went for these kits, that basicly take away a perfectly good, very durable Bendix Mag and give you a crappy Slick? When I take a Bendix mag apart I look for what's bad. When I look at a Slick, I try to find what's good.

I got side tracked a little, but look, if you want your engine to work, and to work like it should, rather than complaining about this and that, get it to a good shop that has experience in doing the stuff. I mean, I am honoured to be working with a mechanic that has more than 50 years working on engines, carbs, mags and anything else you can dream of. I mean I've learned more from him, in 8 months, than I did in college in 2 years, or before that with a specialty turbine shop.

Anyhow. I hope I didn't rub anyone the wrong way.

Nobody said anything about wanting the newest stuff on the market, if I wanted that, I would have bought AFP's fuel injection.

What I want is for my RV to start out with all AD's and SB's that I can afford to comply with complied with. Not that I have to, because I want to.

I think most of us know our limits and know when to consult an expert. Thats the great thing about experimentals. We don't have to take it to anyone unless we want to.

Don't really see anyone complaining here (almost no one), I am happy with my carb and the fact that I repaired it to meet the SB/AD myself without paying an A&P to do this simple task for me.

But you have to agree... that is a stupid SB.
If your float was bad... sure... it helps to replace it, but if you are sitting there, reading that SB and thinking... oh ****, I have to do this now... its a waste of effort.
Soon Volare will come up and state... oh, fiddlesticks, you know that SB... well oops...
The one thing that really rubs me the wrong way: Volare bought up Precision in December. In July I spoke to some of the pencil pushers there to ask them about new manuals and stuff, cause like you we have to keep up with the OEM, they have still to get their act together and post something, even on their website.
But hey.... that's why its an aviation industry, better than the auto!

Lycoming Carburetor Float Failure

Just wanted to relate my recent experience regarding the Volare (aka Tempest, Precision or Marvel) MA4SPA carburetor on my new (70 hour) Lycoming O-320 engine purchased from Vans in 2007.

Last week returning from a short X-country flight my engine almost died after landing during the rollout. I have about 70 hours on the new Lycoming and prior to this have had absolutely no problems with the engine. For some reason the engine did not want to idle but would die or run very rough, it would run fine at power settings but would not idle. I pulled the cowl and tried adjusting the idle RPM and mixture but nothing seemed to help the situation except manually leaning the mixture via the cockpit mixture control. I knew about the recent service bulletin for the carburetor float and my carburetor was one of the units requiring the SB but I thought I could at least fly the airplane this summer keeping the total hours under 100 before pulling the carburetor and having the service bulletin addressed, besides I thought if the float stuck or sunk, the carburetor would leak fuel and run rich at all power settings but that was not the case. Not wanting to get into the carburetor myself, I sent it off to be tested, rebuilt and have the SB applied. When the shop got the carburetor they said it ran fine on their test bench for about 5 minutes then went way rich on idle, same as what I observed. They opened up the carburetor bowl and sure enough one of the two white Precision pontoon floats was half full of fuel causing the overall float level to be low allowing too much fuel into the bowl and causing the idle mixture to be way too rich. I had drained the fuel from the carburetor prior to shipping so the leaking float must have also drained and it took 5 minutes to fill back up with fuel and cause the problem. I guess I?m surprised the float failed after only 70 hours of operation. They must not have tested that float design very well prior to implementation.

Anyway, the company I sent the carburetor to for rebuilding was Quality Aircraft Accessories in Tulsa, Oklahoma and I can?t say enough about how pleased I am with their service. They called me as soon as they received my carburetor to confirm they got it. The following day the technician working on the carburetor called me to tell me what he found and although my instructions were to have it rebuilt, he told me because the carburetor was so new that just applying the SB would fix the problem and a complete rebuild was unnecessary thus saving me several hundred dollars. They called me again the following day to tell me the carburetor had been repaired and to arrange payment and return shipping. The carburetor was delivered back to me exactly one week after sending it in without any expensive overnight shipping charges either direction. I installed the carburetor back onto my engine the following day and it works great, mixture correct and smooth idle at 650 RPM!

So, anyone with a carburetor that needs the float service bulletin may want to consider doing it sooner rather than later. At least note the symptoms I had and if you experience similar behavior the carburetor float should be high on your list of suspects.

ahhh, the joys of traditional aircraft engines.

sorry couldn't resist since i know if it was a subaru/ any alt. engine someone would be a long with- "this wouldn't happen if you'd put an airplane engine in your airplane!"

The really sad part of my story is I intentionally went with a new Lycoming carbureted engine with dual magnetos because I wanted something very reliable and didn’t want to deal with any bleeding edge technology like electronic ignition or even fuel injection. As it turns out, my new supposedly trouble free Lycoming engine had mandatory service bulletins out on its magnetos and carburetor before I could even get the airplane into the air, go figure. You’d think they would have this 50 plus year old technology sorted out by now.

647jc said:

The really sad part of my story is I intentionally went with a new Lycoming carbureted engine with dual magnetos because I wanted something very reliable and didn?t want to deal with any bleeding edge technology like electronic ignition or even fuel injection. As it turns out, my new supposedly trouble free Lycoming engine had mandatory service bulletins out on its magnetos and carburetor before I could even get the airplane into the air, go figure. You?d think they would have this 50 plus year old technology sorted out by now.

Click to expand...

Joe,
I fully understand your sentiment, but this can also be looked at in a different way...
Even with the antiquated, ultra simple technology, you still had a failure at a very low time in service, but in this case it still flew you home (vs a forced landing somewhere). Point is...Basic technology can sometimes tolerate some level of failure and keep your engine running, were other technologys can not.
I don't want to start another alternative engine versus Lyc debate, just pointing out that there (sometimes) are advantages to simple. (I am fully aware of of the long MTBF of some of the newer technologys)

That doesn't mean I have accepted the float problem...I myself replaced three leaking floats in about a years time (2007-2008) and because of my distrust in them I changed out two more that weren't yet leaking. All were replaced with metal floats from Kelly aerospace (yea, once again back to the metal floats). No problems with any of the five airplanes since.