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Author Topic: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later  (Read 4299 times)

aholmes100

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Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« on: December 31, 2021, 03:52:10 am »
About a month ago developed an issue on the start on the Right Engine would not spool up at the speed I generally observe so I thought I would get a hung start so I shut it down. Tried the Left engine it worked. Fired up normally. Then with Gen on the left side turned on got he right engine started but still it seemed a bit slow.

Flipped the battery switch to series and the right engine would start up but seemed a bit slow getting going. Once it got going everything seemed normal. Called Burce and Scott at Byerly in Peoria and flew it over to see if it was the batteries or the battery relay. The batteries on my 690B are new so that was determined not be an issue. According to Ryan at Byerly it was not getting enough fuel on the start.

So first they sent the Fuel Sensor Unit or probe (Not sure if I am using the right terminology) to the Bendix authorized repair center. Apparently there is only one shop that works on Bendix fuel control systems in the US. They have a monopoly and they seem to take full advantage of the fact that they are the only one's that are authorized to work on these.

Ryan sent both the Fuel Sensor units to get bench tested and the right one failed. So that had to be reworked or whatever they do - $ 12,000 spent. It came back was put on the airplane did not fix the problem. Ryan did not want to send the Fuel Control's because he said they always find faults and he wanted to see if this would remedy the issue. Next came the fuel control unit.

They could take mine and work on it but it would be 3 weeks.  That would cost $ 36,000 or send me one they had as replacement off the shelf for $ 46,000. I did not want the aircraft down so opted for the $ 46,000 option. (Foolish decision now in hindsight)

It came back was put back on the airplane still it did not fix the issue. According to Byerly it was not rigged right. They kept going back and forth finally got Honeywell Tech's on the line still this company that was paid $ 46,000 would not accept that the fuel control unit was not rigged correctly. They charged Byerly $ 3,000 for whatever adjustment Byerly tech had made during rigging. They had to bench test it again and again re certify it. I guess anytime you put a new fuel control unit on you have to re rig a bunch of stuff. That messes up other setting.

Next the props would not come off the locks. So they went and looked at the prop govner. Ryan offered me the option that one of the Byerly techs could work on it and try to get it to work or they would send to the shop that works on these and have it done there on the bench. I chose the recommended safer route of paying to get it done by the shop that work on these. Atleast this shop tuned the prop govner around in 2 days.

Finally after a month and a half $ 71,000 spent just brought it back today. Seems to fly better and the yaw that I was getting when I pulled the power back is reduced. It seems that this company abuses everyone across the board and gave Byerly Aviation a very hard time and would not accept any responsibility. From what I have been told this is not the first time and these folks are not the most pleasant people to deal with. I don't know their name. I would imagine Bruce would know exactly who this company.

I bought my 690B on July 1, 2021 and since then I have put 120 hours on it. Apparently with Bendix fuel control Unit this issue can happen if you don't fly a lot. I have been working out some of the things that have come up because I just don't want to kick the can down the road. Prior to my purchasing the airplane may be it sat and did not fly a lot in the past couple of years.

So far if I was to count I have spent about $ 110,000 since July 2021. One was the AC that went after I started flying. Got the compressor replaced, fuel hose leak so had to get that done and all the carpet in the baggage area. And some other but relatively minor stuff. Before I bought it the previous owner had to fix about $ 160,000 in discrepancies.

Bruce felt it was a good -10 with updated avionics and low hours on the engines. I am happy with the purchase still just some of these issues are frustrating. The AC, Fuel hose or this Fuel Control Unit issue not really something that would come up in a pre buy because from what I can tell all the issue were addressed before the purchase.

I had a similar thing with a Malibu I owned. It had not flown much by the previous owner and the first year of ownership it was just one thing after another until I got all the issue workout. Then besides oil change and some minor squawks it was trouble free.
While they were at it I wanted the right engine again scoped just for my piece of mind. I never had a hung start but I may to be a fault am cautious. Everything was good on the borescope inspection.

Happy the airplane is back but sometimes with these just throwing money at these problems does not necessarily fix things right away. Not sure if it's just me but the first year of airplane ownership is frustrating at best. Not sure if anyone else has experienced this fuel control problem. I am hoping this takes care of the issue.

donv

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #1 on: December 31, 2021, 01:36:47 pm »
Sorry to hear about that! It seems like every airplane (and vintage car, for that matter) that I have purchased has had various teething problems. I think I had to overhaul my fuel control units early in my ownership, but fortunately they were Woodwards.

Can you convert your airplane to Woodwards? I know I've flown 690s with Woodward governors. Or maybe that was prohibitively expensive?

aholmes100

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #2 on: December 31, 2021, 01:51:27 pm »
Donv - Not really sure about the cost of the Woodward Fuel Control Units cost, but I would be certainly curious.

An airplane needs to be flown. The more it flies the fewer the squawks if the owner is on top of the maintenance. Some of these issue seem to be one of those things that are going to some up. Some are just related an airplane sitting and poor maintenance history. The pedigree of an older airplane is very important and chain of folks that owned, flew & maintained it.   

donv

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #3 on: December 31, 2021, 01:56:31 pm »
I think the very last 690Bs had Woodwards from the factory. So I'm not sure if there is a conversion or not, but I would think there is.

Adam Frisch

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #4 on: December 31, 2021, 03:37:36 pm »
Sorry to hear all this. That's very frustrating and can really take the shine off of new ownership. As you already know, it's not uncommon to expect elevated catching-up stuff in the first year, but still, it really sucks when it's that much. Especially when there seems to have been perhaps redundant steps. But hopefully this is now it for big expenses for awhile and it will even out over the years. You have now hit two of the three real wallet-busters in TC ownership: windscreen, fuel control and environmental stuff. Let's hope it stays there and only the regular/cheaper stuff will rear its ugly head from now on.

As an aside, always heard really terrible things about the Bendix system costs and service. Sounds like they're all true. Maybe it's time to start warning people about them? One more thing: the -14 engines has a digital FCU and with todays technology it seems like it would be the easiest thing in the world to develop one for all the others. Rather than all this bellows and linkage monkey-motion of the Bendix/Woodwards, just have an electric fuel pump that is digitally regulated for temp and alt do the job instead.
Slumming it in the turboprop world - so you don't have to.

donv

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #5 on: December 31, 2021, 04:48:29 pm »
What do the new production -10s have on them? I think still the Woodward system?

Steve binnette

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #6 on: January 01, 2022, 03:22:18 pm »
That’s nuts!  Sounds like you are making good calls on the repairs.  120hrs is a lot of flying.

aholmes100

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #7 on: January 01, 2022, 04:05:36 pm »
I have about 28 hours left probably will end up flying that in the next 1.5 months. With the amount I fly I think I will end up flying it about 250 hrs a year so will end up doing a 150 hr rather than the annual.

The expense part of it is what it is. It's just the frustration that goes with it. The first aircraft which was a Malibu I just did not take it to the right people because I did not know any better. Once I took it to the right service center immediately things came online. With this one I had the right guy (Bruce) help me with the purchase and Byerly In Peoria did the pre buy but some of the stuff that has come up can't be put on them. Some of this stuff are just things that if it had been flown frequently would have been known and would have been addressed.

My only though with this whole thing was the Phrase I have heard - Don't buy an airplane that is bigger than your budget. Comes ringing back. At least I could afford to get these issue addressed if I was on a very tight on my budget it would end up being a hanger queen and things would get worse by the day because from what I can tell the more an airplane sits the more things go wrong.  So I am grateful that I could at least get the darn thing addressed and back in the air.

donv

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #8 on: January 01, 2022, 08:01:50 pm »
I couldn't agree more about not buying an airplane that is bigger than your budget. That's one reason why I like my 980!

Sometimes it just takes time and money to get things sorted out. The good news is that usually, once you get past that sorting period, they become pretty reliable and more in line with what you were expecting.

donv

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #9 on: January 01, 2022, 11:17:08 pm »
Something to point out is that a 150 hour and an annual should be the same. So if you are flying 250 hours per year, you will probably end up doing an extra 150 hour every other year. That's not too bad.

That's assuming your flying is relatively spread out through the year-- if you do all 250 hours over just a few months, then that might change things a bit.

aholmes100

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #10 on: January 02, 2022, 12:28:53 am »
Donv - I was under the impression 150 Hr or Annual are the same. Either Or. If you reach 150Hr then you are doing an annual at the same time. So from understanding I am have to do the Annual every 7 or 8 months. I am not sure all the things that are involved in an annual. So hopefully it's not too excessive.

donv

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #11 on: January 02, 2022, 12:33:50 am »
Right, we're saying the same thing. So you are doing an annual/150 hour every 8 or so months. So in one calendar year, you will do one, the next one you might do two.

Adam Frisch

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #12 on: January 02, 2022, 11:30:11 pm »
Don - I don't do annuals, just phases. I'm on the factory 100hr schedule. If I only fly 50hrs/year, it's only every 2nd year. You do and annual as well as phase? Except for maybe the bungees, I don't know of any calendar items on mine.
« Last Edit: January 03, 2022, 01:09:29 pm by Adam Frisch »
Slumming it in the turboprop world - so you don't have to.

donv

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #13 on: January 03, 2022, 12:32:32 am »
Yes, I believe you have to do an annual inspection. If you fly more than 100 hours (on yours, apparently-- the newer airplanes are 150) then you have to one at the hourly intervals.

Read 91.409, which requires either an annual inspection or a progressive inspection program (approved by your FSDO). However, the progressive inspection "shall provide for the complete inspection of the aircraft within each 12 calendar months and be consistent with the manufacturer's recommendations, field service experience, and the kind of operation in which the aircraft is engaged. "

If you don't need to do an annual inspection, I'd like to understand how.

EDIT: Maybe the manufacturer's recommended inspection program for the 680 series doesn't require an annual inspection? That seems weird, but I suppose could be true?
« Last Edit: January 03, 2022, 12:34:42 am by donv »

Adam Frisch

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Re: Fuel Control Unit & Fuel Sensor Unit - $ 71,000 Dollars later
« Reply #14 on: January 03, 2022, 01:11:20 pm »
That's how I've always been told it was, but I have to admit I've not myself read the inspection intervals wording.
Slumming it in the turboprop world - so you don't have to.