Why I'll never buy another Marvel-Schebler carb

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SoloEqs

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Back in 1993, the FAA issued an AD on the Marvel-Schebler MA-3 SPA carb, because of poor design of the venturi.

The fix was to modify the carb, and most 150s got that mod, including the one I recently bought.

Then it turned out that the guys who had screwed up the design of the carb had screwed up the design of the FIX. Carbs with the new venturi were running rough and rich, because the new venturis didn't work well with the original fuel nozzle.

Thus, another fix was released, this time a replacement of the fuel nozzle, with one that has holes drilled into it to increase vaporization. Their bulletin said that they would send the kit, free, to anyone who reported the problem.

My plane was living at sea level at the time, and the problem didn't exhibit itself, so the owner didn't get the fix.

My plane is now at over 4600 MSL when it's parked in the hangar, and is showing this problem so much that I don't feel safe flying it until it's cured.

However, when I contacted Marvel-Schebler, I was told that the price of the fix was nearly $160! The fix consists of one brass nozzle and a couple of gaskets, about $10 worth of parts.

The company refuses to honor the earlier no-charge fix because it's been years since it was developed -- though the notice from the company detailing the problem and the fix didn't specify any time limit for them to make good on the fix for their botched venturi / nozzle combination.

I could agree with their position, if there were any use for the kit other than returning their product to a pre-AD level of safety. Since there isn't, the only question is when the fix is applied.

As I'm currently on a very tight budget, spending $160 for this fit simply isn't doable.

However, the FARs permit owners to make their own parts, within certain restrictions -- one of those being that you can't simply reverse-engineer an existing part, you have to get the data from the manufacturer.

I just got off the phone with Marvel-Schebler. Not only will they not budge on sending the kit, they also won't give out the "proprietary" information on the number and size of the holes in the nozzle (which would allow me to modify the existing part or machine a new one).

I will try to find one to look at, or check around for a junk MS carb that has the nozzle.

The 150 is the only production plane I own. I have a couple of experimentals, and am in the process of building several others (once my employment situation improves). I am also the "guru" for a number of folks around here who are building their first EABs.

I'm stuck with the Marvel-Schebler for the 150, but fortunately my other planes are set up with a Stromberg, an AeroInjector and a dual-Mikuni set. I will put AeroInjectors on the planes which are still under construction, when I have the money to resume building.

I'm also sending copies this information to all of the local builders that I've been helping, advising them not to buy MS carbs. Anyone who does is on their own, as far as their fuel systems -- not only will I not provide any support for Marvel-Schebler products, my experience indicates that the company won't provide much, either.

A carburetor has one purpose, to MIX FUEL AND AIR in the proper proportions.

The Marvel-Schebler MA-3 SPA used to do that, before they pushed an AD onto us (forcing owners to buy parts). NOW they demand an additional $160 so that it will once again do what it did before they "fixed" it.

This is unacceptable.

When a company is so unwilling to stand behind their product on a SAFETY OF FLIGHT issue -- especially one with is a result of THEIR OWN MISTAKE (in the failure to perform adequate testing of their venturi and fuel nozzle) -- I am not going to give them a penny, and will tell others about it, so they can decide for themselves.

Let's also not forget that a few years ago, they were telling us to buy their new, improved foam floats, and now demand that they be replaced with the new, improved epoxy floats. What's next, solid gold needle valve seats?

I've sent a copy of this bulletin to the guy at Marvel-Schebler, to give him the chance to make corrections or offer rebuttal. I will append pertinent portions of any response below.


===

9 AUG 2013
MARVEL-SCHEBLER'S RESPONSE:

Upon forwarding your email to our member managers, I have received the
following response:

" You are permitted to tell him that I said his childish behavior is a
disgrace to our aviation community. We assist too many global aviators on a daily basis to be bullied by this self professed "expert". He is free to
proceed in any manner he wishes but if he liables our fine company it will
not go unaddressed by our legal team."


Mark Keeney Jr.

Marvel-Schebler Aircraft Carburetors, LLC.
125 Piedmont Ave
Gibsonville NC 27249

Mark@MSACARBS.COM
(336)446-0002
(336)446-0007 Fax
1-855-MSACARB
(672-2272)

===

MY REPLY:

Upon reading your managers' response, I have this to offer:

1) The disgrace is for a company such as yours to force a mandatory change on owners which decreases flight safety, then to demand that we pay you even more in attempts to correct for your low standards of R&D and testing.

2) Your single-venturi / nozzle combination would not meet the testing standards for a Supplemental Type Certificate.

3) It's "libel," not "liable," and I would welcome the opportunity to discuss the policies of your "fine company" in court -- especially if your legal team is of the same caliber as your customer support and engineering teams. Since you are unable to offer any actual counter to the points that I've raised, I would enjoy watching you try to prove that I've said anything
which is not true. In fact, I sent you the notice of what I'm writing so that you could make any corrections to what I've said. You have failed to find any corrections to make, instead falling back on the time-honored tradition of becoming angry and offensive when your flaws are made public.

You should stick to spark plugs and oil filters. Those are actually worth the money, and easily replaced if you screw those up, too.

===

So, the bottom line is that Marvel-Schebler has SELF-RIGHTEOUS honed to a fine art, but carb engineering . . .not so much . . .

MS is owned by Tempest, the people who make great spark plugs and great oil filters, but fortunately, neither of these products needs much in the way of customer support. I continue to endorse both of those products, which obviously weren't developed by anyone who had a fingerprint on their carbs.
 
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You're in aviation, and $160 isn't doable? Maybe you need to find a new hobby, like, knitting.
 
bartmc said:
I agree with the sentiment, but that was a very douchebag response by Mr. Keeney.
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Yeah, no argument there. And I completely get refusing to spend $160 on principle, as I've done it many times. But if $160 isn't doable, come on. I'd be happy if a fix was only $160.
 
Find a two piece venturi and reinstall it.


Happy flying!
 
Good Grief.

It's only 160.00. If 160.00 is too much then perhaps taking up fishing with a cane pole is better suited.

Wal-Mart and the like, have soured the consumer public into thinking that warranties, returns, refunds, are forever. I don't really care for Mr. Keeney's response but he answered an unreasonable request with an unreasonable reply.

Where is that tiny violin emoticon?
 
Gee, I appreciate all of the warm responses with guys who haven't recently lost their income. ;)

I work on contract, and it's generally feast or famine. Since I don't know when my next contract will come along, I'm running on my savings and not wasting a dime, and can only justify the costs of flying an hour or so every couple of weeks in my C150 by giving up pretty much all other forms of entertainment.

I certainly don't have money for a repair kit which should have been sent free 20 years ago -- to fix a "fix" which should have never been mandated in the first place!

That $160 buys a brass nozzle, which can't cost any more to make than the brass fittings that Home Despot sells for $4, and a couple of gaskets. So, no, $160 isn't doable. I need that extra $150 more than they do.
 
Agreed they screwed up a fine carb for a lack of proper inspections. Put the two-piece back in.

If $160 is tight and you own multiple aircraft, it's time to sell one. Seriously.
 
bnt83 said:
Find a two piece venturi and reinstall it.
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Wish I could!

Instead, I'm going to try to find a nozzle to take a close look at. After I see what changes they made, I can probably improve on it and go for an STC.

One key difference between my nozzle and MS is that I'll have to actually TEST the new part . . . :rofl:
 
denverpilot said:
Agreed they screwed up a fine carb for a lack of proper inspections. Put the two-piece back in.

If $160 is tight and you own multiple aircraft, it's time to sell one. Seriously.
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Concur.

Of the three flyable planes, I have one of them on the market (for about 2/3 of what it's worth), and have sold parts from the other experimental. I'm also trying to sell a motorcycle, a car, a 4WD ambulance (really!) and pretty much everything else I have other than my home and the 150.

The real problem is that the work I do pays VERY well, but if I go outside of the industry for another job between contracts, that would make it almost impossible to get the next contract. And the expected contracts this year have been put off -- possibly until next spring -- thanks to the economy.

So, I'm just trying to have enough money to ease through. If I were on a contract, I probably would have just ordered the kit.
 
Who cares what the dollar amount is - they screwed up - and it'll cost them essentially nothing to make it right. Instead of making it right they chose to write a 5 year old response to one of their customers.

I'll be avoiding them as well.
 
I'd say you're lucky that M-S ever offered the parts for free at any time. Good gravy, how many ADs (not to mention SBs) require parts and labor well into the AMUs to implement, and the companies involved never offer to share any of the expense with impacted customers?

I have little sympathy here. Sure, M-S had an opportunity to go above and beyond, and didn't. That's a too bad. Now, put on your big boy pants and move on to the next first-world problem.
 
FWIW, ALL service bulletins have a LIMITED time where credit for parts and/or labor will be (if at all) reimbursed nowadays. Pretty naive to expect or believe an OEM would do "the right thing" long after the fact.


For instance, many OEM's DO NOT allow just any Joe Blow to apply for the credit, instead it must be accomplished by an OEM authorized service center and some must be accomplished by an OEM owned service center.
 
jesse said:
Who cares what the dollar amount is - they screwed up - and it'll cost them essentially nothing to make it right. Instead of making it right they chose to write a 5 year old response to one of their customers.

I'll be avoiding them as well.
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Well, good luck with that. Most of us with certificated airplanes, especially older ones, don't get to choose what carbs go on our engines.

While I agree that Marvel Schebler really should "make it right," expecting a company to warranty a fix forever is unreasonable. Neither auto manufacturers nor electronics manufacturers do it, as evidenced by the sometimes dozens of service bulletins issued for fixes to problems with their products. Those fixes don't get offered or applied for free, typically, unless the vehicle or product is within a warranty period, and they don't get offered at all unless the consumer reports a problem relevant to the fix.


JKG
 
JGoodish said:
Well, good luck with that. Most of us with certificated airplanes, especially older ones, don't get to choose what carbs go on our engines.

While I agree that Marvel Schebler really should "make it right," expecting a company to warranty a fix forever is unreasonable. Neither auto manufacturers nor electronics manufacturers do it, as evidenced by the sometimes dozens of service bulletins issued for fixes to problems with their products. Those fixes don't get offered or applied for free, typically, unless the vehicle or product is within a warranty period, and they don't get offered at all unless the consumer reports a problem relevant to the fix.


JKG
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In this case we're talking about a small baggy worth of parts worth essentially nothing that are a direct result of them screwing up a design and instead of them doing something reasonable they instead choose to gouge their customer for their mistake and then write some ridiculous 5 year old e-mail to said customer.

If this were a $1,500 part I'd agree that they can't just give it away. In this case we're talking about a small chunk of brass that they probably have bins full of.

If you want to see how aviation companies should behave, look at Lightspeed.
 
Precision Airmotive Corp Service Bulletin MSA-7 dated 9/30/94:

Improper installation of the one-piece venturi can also result in the symptoms described above. It is very important to install the venturi using the proper tools and the procedures described in the overhaul manual. In addition there are a number of other conditions that can result in a rich running carburetor for instance:

leaking primer system, improperly adjusted float height, leaking bowl gasket, improper fuel nozzel installation"


Warranty-

Operators who have installed a Prescision Airmotive one piece venturi in their carb and experience the sympotoms described in section 1 MAY BE eligible for warranty credit on the 666-942 kit. Those requesting warranty will be RQUIRED follow warranty instructions provided in the kit. (Note: in order to receive warranty you MUST be able to show that a genuine Prescision Airmotive venturi was installed in the carburetor.)


SOP from any OEM.

There's been so many different manufacturers dinking with the same design, I can't blame them.
 
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JGoodish said:
Well, good luck with that. Most of us with certificated airplanes, especially older ones, don't get to choose what carbs go on our engines.

While I agree that Marvel Schebler really should "make it right," expecting a company to warranty a fix forever is unreasonable. Neither auto manufacturers nor electronics manufacturers do it, as evidenced by the sometimes dozens of service bulletins issued for fixes to problems with their products. Those fixes don't get offered or applied for free, typically, unless the vehicle or product is within a warranty period, and they don't get offered at all unless the consumer reports a problem relevant to the fix.


JKG
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In the case of recalls (equivalent to ad) auto manufactures do. I've have had things fixed per the recall MANY years after the recall was issued. A poor comparison, I agree, but you wrote it :)
 
Well, I'm in the awkward position of correcting the correction. The primary tube that picks up the fuel gets holes drilled in the side and they are called 'emulsion' tubes which mix air with the fuel from the main jet. The fuel is not vaporized actually, but it is atomized in the stream exiting the main jet where it enters the venturi. Emulsion tubes come in various types with different location and size of holes.

If you can find one on a carb sitting in someone's shop take it out, and use a drill gauge to figure out the size, and take some pics to figure out the location and this will be your reverse engineered method. Of course, it must be made of compatible materials, with equal strength, elasticity, etc as the original material which I suspect is a brass or bronze deal.

I also feel pretty bad about sending money to a company that mis-engineered a part which was a mis-engineer fix to an OEM product. I think the company should be responsible for their mistakes in this case.

It brings to mind one of the real messes of the AD system as it related to Grumman. For a short time back 20 years ago or so the FAA found some corrosion at the back of the ailerons on some of the AA5 planes. So, between the FAA and Grumman Amer they decided the fix was to just cut off the after end of the whole aileron, and rivet the skin to a small bulkhead, leaving a blunt trailing edge to the aileron. Well, that went on for a while, and some planes were modified, then the FAA mandated that this practice stop, and at first they said every owner had to go get new ailerons to replace the ones that they deemed a problem and provided a 'fix' for. WHAT! The owners rose up in indignation and that part of the AD was rescinded. So, now there are some AA5s out there with blunt ailerons, and some with tapered ailerons. Both are airworthy provided there is no corrosion. Thanks....
 
jesse said:
In this case we're talking about a small baggy worth of parts worth essentially nothing that are a direct result of them screwing up a design and instead of them doing something reasonable they instead choose to gouge their customer for their mistake and then write some ridiculous 5 year old e-mail to said customer.

If this were a $1,500 part I'd agree that they can't just give it away. In this case we're talking about a small chunk of brass that they probably have bins full of.
Click to expand...

That, however, is the problem. While M-S could and perhaps should "good will" the parts, there has to be a fairly uniform line that is drawn for these types of issues, regardless of cost.

And, IMO, expecting a free fix years after the fact isn't in any way reasonable.


jesse said:
If you want to see how aviation companies should behave, look at Lightspeed.
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I wonder if LS will fix every problem for free forever. Where is that guarantee?


JKG
 
You mean Marvel-Schebler Carburetors don't stand by their customers? Surely that can't be the Marvel-Schebler Carburetors I know. However, Marvel-Schebler Carburetors douchey reaction warrants an apology and correction from Marvel-Schebler Carburetors.
 
jesse said:
In the case of recalls (equivalent to ad) auto manufactures do. I've have had things fixed per the recall MANY years after the recall was issued. A poor comparison, I agree, but you wrote it :)
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Auto manufacturers are compelled by the government to issue recalls and fixes for certain safety-related items, but those are rather rare. Most product defects are not recalls, and ADs also typically have a deadline issued to the owner or operator for compliance. In this case, it appears that the fix and timeline were completed to satisfy the AD.

It's also worth noting that no manufacturer can guarantee fixes in perpetuity, including auto manufacturers affected by mandated recalls. There is always a deadline beyond which the fix is no longer available.


JKG
 
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JGoodish said:
That, however, is the problem. While M-S could and perhaps should "good will" the parts, there has to be a fairly uniform line that is drawn for these types of issues, regardless of cost.

And, IMO, expecting a free fix years after the fact isn't in any way reasonable.




I wonder if LS will fix every problem for free forever. Where is that guarantee?


JKG
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Actually IME Lightspeed fixes pretty much anything you send them no questions asked. If they were sitting on $2 worth of parts that meant you flying or not flying they would send them to you for free. They sure the hell wouldn't try and charge you $160 for it, especially if the part was to fix their original flaw.
 
jesse said:
Actually IME Lightspeed fixes pretty much anything you send them no questions asked. If they were sitting on $2 worth of parts that meant you flying or not flying they would send them to you for free. They sure the hell wouldn't try and charge you $160 for it, especially if the part was to fix their original flaw.
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The question isn't will they fix it, the question is for how long will they fix it for free?


JKG
 
JGoodish said:
The question isn't will they fix it, the question is for how long will they fix it for free?


JKG
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I sent them a headset that had been out of warranty for 7 years, and they said they would fix it for free, but they then offered me $500 to trade it up for the Zulu 2 so I did ($200 more trade in than listed)
 
I guess if MS profit margin was 95% per copy, they would have better service.
 
bnt83 said:
I guess if MS profit margin was 95% per copy, they would have better service.
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Doubt it - since they don't seem to care about customer service since they actually wrote and sent to a customer:
" You are permitted to tell him that I said his childish behavior is a
disgrace to our aviation community. We assist too many global aviators on a daily basis to be bullied by this self professed "expert". He is free to
proceed in any manner he wishes but if he liables our fine company it will
not go unaddressed by our legal team."
Click to expand...

Great customer service takes serious commitment from the top down. Most companies can't pull it off.
 
jesse said:
Doubt it - since they don't seem to care about customer service since they actually wrote and sent to a customer:


Great customer service takes serious commitment from the top down. Most companies can't pull it off.
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Agreed.


My experiences with white coats would alarm you. Do a procedure twice because they botched he first, you get billed twice.
 
JGoodish said:
That, however, is the problem. While M-S could and perhaps should "good will" the parts, there has to be a fairly uniform line that is drawn for these types of issues, regardless of cost.

And, IMO, expecting a free fix years after the fact isn't in any way reasonable.
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Why not?

The carbs were working, before MS pushed out a mandatory AD which screwed them up.

When this was discovered, a responsible company would have pushed out a mandatory AD to correct the problem, rather than only sending the kit to those who discovered the problem soon enough and complained.

Instead, they're tacking $150 worth of profit to a part which is only of useful to correct the problem which MS CREATED.

It would be different if this were an expendable part with a limited lifespan, which would need to be replaced anyhow, or it if were a part which would be of value for anything other than correcting a problem which was directly and solely the result of slipshod design testing of the original mandatory AD. If any of those were true, it would be possible that someone seeking the kit would be trying to cheat the system.

Since the kit is only of value to correct the problem, what does it matter WHEN the complaint arises?

Imagine being forced to pay an A&P to cut a chunk out of your propeller, then being forced to pay 16 times the cost of another chunk that is to be welded back in. What is "reasonable" about that?

BTW, as far as recalls on cars, I mentioned the 4WD ambulance that I want to sell. It was built in 1986, but when I bought it last year and stopped by the dealer to get a build sheet and information, they found a minor recall that hadn't been done. The parts and labor cost several hundred dollars, on a recall issued 25 years ago, and the only question the dealer had for me was whether I wanted to leave the wagon or come back the next day, after the part was overnighted.
 
docmirror said:
If you can find one on a carb sitting in someone's shop take it out, and use a drill gauge to figure out the size, and take some pics to figure out the location and this will be your reverse engineered method. Of course, it must be made of compatible materials, with equal strength, elasticity, etc as the original material which I suspect is a brass or bronze deal.
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I suspect it's the original part with some extra holes drilled in it.

I'm trying to find someone with one that I can look at (or pictures).

I even told the MS guy that I was willing to fab or modify the part, if they would tell me what size holes and where they go. That's when he got huffy about "proprietary" information.

Again, if this information were of value for anything other than correcting their mistake, I would understand keeping it secret, but that's not the case.
 
jesse said:
In the case of recalls (equivalent to ad) auto manufactures do. I've have had things fixed per the recall MANY years after the recall was issued. A poor comparison, I agree, but you wrote it :)
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And sometimes they convince regulators, even on safety items, to mileage limit the fix. Case in point: Almost every Chevy/GMC dashboard cluster from 1999 through 2006 used servos that didn't meet spec and fail, leaving you at best with a bad electrical voltage indicator, at worst a speedometer that doesn't work or even hangs at particular points in its travel.

It was a free fix to a certain mileage. Now it's not. The problem with that us, hundreds of thousands of known bad servos still out there in speedometers.
 
jesse said:
Great customer service takes serious commitment from the top down. Most companies can't pull it off.
Click to expand...

I'm actually amused by their response. I learned a long time ago that when someone is in the wrong, KNOWS that they're in the wrong, and are called out on that fact, the instinctive reaction is to go on the offensive and try to get the victim to back down and apologize.

The self-righteous line about assisting so many "global aviators" actually made me laugh.
 
If only we had a Navion owner here we could ask them about the fuel selector debacle. Imagine this kind of fark up with at least another zero behind the cost.

OBTW, I had a 51YO prop from Hartzell. They issued a SB on it, would cost $300 parts, and $150 labor by their estimate. They sent me a detailed form, I filled it out, the part and a check for $150 arrived in a few weeks from Hartzell. That's what I'm talkin bout.
 
SoloEqs said:
I'm actually amused by their response. I learned a long time ago that when someone is in the wrong, KNOWS that they're in the wrong, and are called out on that fact, the instinctive reaction is to go on the offensive and try to get the victim to back down and apologize.

The self-righteous line about assisting so many "global aviators" actually made me laugh.
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I think there's plenty of blame to go around. I'm not sure how long their "free" window was but if it was 20 years ago, I'd have a hard time placing blame on them for not keeping the program alive for 2 decades. Yes, it was their fault initially and it seems when they found out about it, they fixed it. OTOH, you bought the plane without checking to see if it needed a $160 part (or never bothered to take them up on their offer 20 years ago). I can see both sides point here. What I can't see is why they felt the need to send a petty juvenile reply.
 
Geico266 said:
One word.... fuel injection. :rofl:

In the experimental world we just use what works. ;)
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In the certified world, fuel injection systems get ADs, too. And those ADs mean expensive repairs, usually.

The OP's rant against those carbs I can identify with. After having looked after lots of flight school airplanes, most of them with those carbs, I've seen a large variation in consistency of performance in them. One will run OK, the same part number in an identical airplane on an identical engine will act up. The AD forcing the change to the venturi made a lot of well-running engines start running like toilets, so Precision (the owners of that carb line at the time) came out with the pepperbox nozzle. That didn't solve the roughness in many cases, so they amended the AD again to allow the old two-piece venturi to be reinstalled provided that it was checked for looseness every 100 hours. But all those parts had been returned to Precision and trashed.

The roughness seems to have been due to the squared-off legs supporting the secondary venturi. The old two-piece had nicely streamlined legs that let the airflow go around them without turbulating. The squared-off legs presented a flat face to the incoming air and screwed up the flow around the fuel nozzle. I know a guy that experimented with carving those legs to match the original design, and he got smoothness.

Dan
 
bartmc said:
I think there's plenty of blame to go around. I'm not sure how long their "free" window was but if it was 20 years ago, I'd have a hard time placing blame on them for not keeping the program alive for 2 decades. Yes, it was their fault initially and it seems when they found out about it, they fixed it. OTOH, you bought the plane without checking to see if it needed a $160 part (or never bothered to take them up on their offer 20 years ago). I can see both sides point here. What I can't see is why they felt the need to send a petty juvenile reply.
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I would agree with you (and them) about the time frame, if A), the whole problem weren't solely a direct result of their forcing the initial UNSAFE modification, and B), if the kit had any use other than correcting for their mistake and improving flight safety.

They broke it, they know they broke it, and the fact that it took so long to discover that they broke it doesn't make them any less culpable.

To then turn around and demand $160 for $10 worth of parts to fix their mistake is ludicrous.
 
Dan Thomas said:
The roughness seems to have been due to the squared-off legs supporting the secondary venturi. The old two-piece had nicely streamlined legs that let the airflow go around them without turbulating. The squared-off legs presented a flat face to the incoming air and screwed up the flow around the fuel nozzle. I know a guy that experimented with carving those legs to match the original design, and he got smoothness.
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Are there pix anywhere of what the legs should look like, how much rounding they need?
 
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