MichMooney201

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About MichMooney201

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  • Model
    1978 Mooney M20J
  1. IO-360-A3B6D to A3B6 Conversion

    I have done a fair amount of homework on this topic and a far as the FAA is concerned, the conversion is allowed without any additional approvals because there are three engines listed on the type certificate and all are approved engines for use, and there are no serial number limitations listed on the type certificate. As further evidence, if you look on the type cert for K models, note 17 specifically calls out an engine replacement for the TSIO-360-GB series engine to a Lb series engine, because everything is called out as serial number specific on the K's in the type cert. This is not so for the J's, or for any other instance where an air frame has a call out specific to a serial number. Note 12 on the type cert also clearly spells out engine can be converted, for the A1B6-D to the A3B6-D. We have not done an engine conversion, but a replacement. Additionally, there is no conversion of the air frame to hang the A3B6. When I talked to Mooney, there are no specific changes needed to be made to hang the motor as everything has already been spelled out in parts manuals for the A3B6,(prop gov bracket and hoses), where service bulletins are issued with additional instructions if there has not previously been written communication from Mooney addressing the service needed to be spelled out. Lastly, the type certificate is the enforcing document in the US, not the parts manual. I was wary enough about the conversion to ask a ton of questions of the popular Mooney service centers before going down this road as they have done a ton of these conversions themselves, and they all responded with they did no additional paperwork or approvals because of how the type certificate is written.
  2. IO-360-A3B6D to A3B6 Conversion

    So I took a photo and checked numbers on the fuel pump and it is model LW-15473 which is a Lycoming rebuild. In looking online for additional info, this same part number crosses to a Tempest AF15743 which calls out a fuel pressure range of 25-30 psi. The original on the type cert is AC products, which is now Lycoming so the LW-15473 is on the type cert and the part number has been superseded to 62B26931. BTW, the Dukes or Weldon fuel pumps are the electric driven pumps, and the LW-15473 is the motor driven. For others having issues, this pump is available rebuilt or new and pricing online was $259-$400 for the correct pump. This should solve over pressure issues, and Lycoming confirmed they are not putting the higher pressure pumps on the A3B6 in the future...at least that’s what the tech guy told me.
  3. IO-360-A3B6D to A3B6 Conversion

    I will research tomorrow and verify the fuel pump that came on the reman and repost what I find out from Lycoming, etc. type certificate clearly calls out the Dukes or Weldon fuel pump. Somehow I overlooked this minor detail...even when I knew there was over pressure issues. Good catch and thank you.
  4. IO-360-A3B6D to A3B6 Conversion

    Robert, what are you referring to specifically needing an approval or STC?
  5. IO-360-A3B6D to A3B6 Conversion

    Luke, I specifically called Lycoming on the fuel pressure issue because the A3B6 is also used on some Beech change outs and so the fuel pump, alternator and prop governor oil lines fit Beech set ups and then the marketing gurus at Lycoming decided to hit Mooney drivers with flyers and ads. So, the mfg bill of materials at Lycoming is for the standard Beech layout, and we get to pay big bucks to buy the parts like the $560 oil line to make the engine fit our planes. That being said, the tech guy at Lycoming checked the model number on the motor coming to me and he assured me the fuel pump on my motor would fall with POH operating specs. We will fire the plane up this weekend and that will be one of the first things I check. They are aware at Lycoming of this issue and have made the changes to a lower pressure pump so that one pump fits both Mooney and Beech builds, so they say. We shall see for sure this weekend.
  6. IO-360-A3B6D to A3B6 Conversion

    https://mooneyspace.com/topic/15898-m20j-io-360-a3b6-conversion-experience/ I wanted to update the Mooney community with a new thread on the conversion process I am in the middle of going through on my 78 J switching to a A3B6 motor from a single drive A3B6D. For anyone else considering this, I have reposted the above link from member dhc which has turned out to be an extremely valuable resource for the conversion. My goal is to update the pricing for needed parts and share some of the issues that were a little different from dhc's conversion, even though both of us have converted a 78 J. The first consideration for anyone is whether a field overhaul, factory overhaul or factory refurbishment is where you want to spend the money. Time for any of these was not a consideration because a field overhaul takes the same amount of time as it does to have Lycoming do its job. All quotes, including factory refurbished were 4-6 weeks, and I stopped flying my J when I started fouling the lower #4 cylinder plug on short final so waiting for an engine while continuing to fly was not an option. 2000 hrs had passed and it was time for a new motor. The cost for a field overhaul from the reputable shops was $27-$29K which included Poplar Grove, Western Skyways and Penn Yan, (varied about $2K depending on factory new or refurbished cylinders). Factory overhauled, (A3B6) from Lycoming was $32K and factory refurbished was $35,500. Interesting to note, a A3B6D is more expensive to refurbish/overhaul than a A3B6 by about $1700. So in looking at cost of ownership over the next 2000 hrs, (10-15 years based on how my plane flys now), the next overhaul would be cheaper on the A3B6 than the B6D. So just in a motor comparison, switching to the A3B6 was about a $3500 upgrade if I look at the cost of the motors and potential future savings at overhaul, $5200 if I take out the next overhaul. So for my plane partner and I, a ZERO time engine logbook, 80% brand new parts engine built to new limit tolerances as opposed to overhaul minimum tolerances, and a significant plane value increase completely made the cost of the factory reman worth the cost. That all being said, there are some gotcha costs involved, including costs that one would bear during an engine change out/overhaul. You will have to purchase some parts that won't come off the A3B6D such as the prop governor brackets and cable mounts, and the prop governor oil line. Prices varied considerably among the shops out there for these parts and G&N was the best for me by far. The new oil line was $560 from LASAR, $452 from G&N for the same part. $452 is ridiculous from Lycoming when it was $280 in 2014 when dhc did his conversion. The cable brackets were another $50 and $75 a piece, and the prop governor brackets were $147 and $175. Rebuilt prop governor is $1250 from West Coast Governor Service, highly recommend Dan there, btw, (former Navy Hydraulic mechanic so he knows his stuff). So there is roughly $2100 in prop governor parts/conversion for the new motor, about $900 increase to change to the A3B6. Oddly enough, there are two different control actuators that you could get on your prop governor which is differentiated by what side of the actuator the set screw is on. This set screw placement will dictate if you need to use the $147 bracket from Mooney or not, we did not and the part was returned, (literally the only cost savings we had in this entire conversion). The alternator that comes with the reman from Lycoming will not fit the baffling on the J so you will have to either use your existing or buy a new one. I had just purchased a new alternator 100 hrs ago so I was good there. New hoses are in order on an engine change and there are some differences because of the oil filter placement on the A3B6 so Ashley from PHT in Tulsa was a great reference there, about $900 for a complete set of hoses. Other than the prop governor costs, everything is the same between the two motors. Lycoming now uses Slick mags and harnesses so the timing on the motor is at 20 degrees instead of the 26 degrees of the Bendix mag setup. If you wanted to go to the Bendix setup you could, but we are installing a Sure-Fly electronic ignition as soon as they are STC'd so the advance timing of the Sure-fly negates the lost power from the Slick mags and is cheaper and better running than a Bedix mag setup. $1250 for the Sure-Fly. Total costs: 35500 motor, 450 shipping, 2100 prop gov and acc, 900 hoses, 150 two cases of oil, 600 motor mounts, 1550 new baffles. $41250.00 to date. Ultimately, the cost of switching to the A3B6 has been worth every penny and because some of the trials detailed by dhc, the conversion has gone relatively smooth. The increase in costs to switch have been minimal because the only real headache is the prop governor, so plan on the extra $1000.