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  • engine cores ?

    Have been scanning the web for O-540 cores.... just to take the temperature of the prices.....
    Mostly what I am seeing are prop strike engines being sold by brokers---- for in the 15 K range...... some not even with
    all the parts included. Is there ANYBODY out there REALLY paying that ??????
    ----for an engine that could have a bad case, crank or both ? and some with no logbook ?????
    I get the impression that the broker-resellers have / are vacuuming up all the cores up before the rest of us even have a chance.
    How do you find a core that has not yet fallen into the clutches of the evil core scalpers ?

    Has anyone found a way around this problem ?

    T
    PS---- as perspective----- it seems O-470 cores are 1/5 the price of O-540 cores.......
    what gives there ????????


  • #2
    I went through the same process and quickly gave up. I have had no connection to light aviation for my adult life. Talking to colleagues at work who have been involved with it, I came to the conclusion that my ability to evaluate a core before purchasing it was suspect at best. There was a huge chance that I would buy a core that would end up being trash. For me, it seemed like the way to go was to just pay the rebuilder for an engine (in my case Bob), and let them deal with finding a good core.

    If I was tied into the local aviation community, or had more experience, I might have trusted myself to do it. I have just heard to many horror stories.

    Comment


    • #3
      Originally posted by fairchild View Post
      Has anyone found a way around this problem ?
      Yes, pay Bob to build you an engine. His cost will be on par with what you'd spend to do it yourself, subtracting the labor and risk of doing it yourself.

      Originally posted by fairchild View Post
      PS---- as perspective----- it seems O-470 cores are 1/5 the price of O-540 cores....... what gives there ????????
      I suspect it is because the 470 is so much less useful and applicable in the homebuilt market, considering the Bearhawk, RV-10, etc. You can buy a DC-3 for 1/5 the price of a King Air, if you really want to.

      Comment


      • #4
        On the O-470 issue----- is the main drawback just the motor mount issue ? (noting that it is a little less HP and maybe same weight
        or slightly heavier than the 540------ )
        Has anyone used a cont-O-360 as a middle gound choice (HP wise) which might put the HP between the Lyc. IO-360 and the O-540. ?
        I am assuming it has a similar mount geometry as the O-470.........
        I see avi-pro is making an O-470 mount for us------ if that theoretically solves the mount issue...... what issues does that leave remaining ?

        You would think that the homebuilt world would be driven to go towards what is available and economical.... not the unobtaneium choice.

        T

        Comment


        • #5
          We installed a Continental IO-360 210 hp with an 84" McCauley CS prop. It was a 800 hour front engine off a Cessna 337 that we got for reasonable. Th engine checked out and has the cold compression of a new engine. The owner of the 337 had more money than the average bear and had both engines removed to put on a pair of larger engines. We were able to get a good deal. The maintenance facility flies 19 of the 337 Cessnas for ministry fire watch and were able to give us a lot of support. The 337 has a pair of Cont 360 push pull engines. We were able to get a rear engine mount out of their bone yard for a $100 that is the common mount modified to install in other aircraft to repower to a Cont IO-360. Bob Barrows gave us the tube sizes to attach the mount & that was a relatively easy mod. Plus is that they are supposed to be reasonable on fuel, they dyno at 210 hp and can swing an 84" prop that is commonly used in longer lengths on IO-470s. The props are common and easy to find. The McCauley C203 prop blades are one length that are cut to the application and have a range of roughly 98 to 76. We bought a first run prop and had it rebuilt for a total cost of of purchase and overhaul for $6000 Cdn about $4k US. The fuel injection is mechanical and our mechanics tell us that it is simple and reliable. Minuses or differences. I heavily modified the standard MC nosebowl to fit around the chin of the engine. Turned out looking really nice and we have run it on some hot days and cooling seems good. The exhaust is custom at about $1500 is a dual header system with two mufflers with heat cuffs. The fuel intake and air are all on the top side of the engine so the underside has clear channel to allow cooling air to have a clean straight exit. Lycomings can use Vetterman exhausts common to RV's. The fuel pressure is a mechanical set up and needs a return line to a header tank or to a fuel tank. There are many debates on returning the fuel but we wanted to go the way of certified aircraft and minimize the fuel flow restrictions. We kept it simple and used a small header tank similar to the Maules or repowered C170 & 172's. We modified a pair of full port fuel valves for on and off on left and right sides. We did not have to do any modifications or reverse the air/fuel intakes as there is lots of room. There is no need for carb heat and the big airbox under the chin. We had to do a few wiggles that were different but all were manageable with our skills and the support of our mechanic friend. The Continentals allow for a very clean cowl. Engine starts quick and runs smooth. Parts & service are reasonable with good shopping. We just passed the final inspection & will be flying in the next month or so. Can let you know how that goes once we have some time & experience. Money wise it is what falls in your lap & is reasonable or the hp to suit the mission. Lycoming 540's will give you all the hp, are proven and well supported. The engine was 24V so went 24V throughout and it was no problem as most electronics go 12 or 24.
          IMG_1138.JPGBH Exh 1.jpgFinal 2.jpgIMG-20160907-00393-1.jpg
          Attached Files
          Last edited by Glenn Patterson; 07-08-2018, 01:17 AM.

          Comment


          • #6
            Thanks for the first hand info Glen....
            Thats a good trick for mocking up your exhaust pipes ! I will have to google to see if the 470 and 360 take the same mount.......

            Funny thing is--- about 3 weeks ago we had a massive momentary wind in the leading edge of a severe thunderstorm which
            was 60 or 70 mph. It flipped 4 or 5 light planes at the airport. Two of them were skymasters. They were parked in a row
            and it lifted one up and deposited it up side down on top of the other plane. I would have thought they were both totaled.
            Right there may be 4 good engines...... if I could find their status........
            I have flown a couple times behind an O-300. it was seemingly smoother than a lyc. I thought. Quieter too I would say.
            Not what you would mistake for a "powerhouse" ... but smooth. It was in an old 172. I am guessing Bobs (avipro?) new engine
            mount is fairly new.... not a pic on the web site of it yet. (o470)

            Will keep looking at the contis ........

            Tim

            Comment


            • #7
              There is a big difference between the size and weight of the engine so the mounts would be different. The 470 is almost 100lbs heavier plus 20-50hp. There are salvage yards that sell the Cessna 337 rear mount. The front mounts in a 337 are aluminum sheet fabrications. There are tons of Cessna 180, 182a etc that used the 470 engines. We had the mount and a bare block so we positioned the stripped mount and added the tubes to the Bearhawk attach points. The rectangular frame with the mounts is the Skymaster part. Machined wood plugs were put in the ends of the block and the string centered in the center holes for alignment. We had the front 337 engine and used its baffles to make patterns for the new BH engine baffles. It would be easiest to work with a front engine.

              These are the folks that built our exhaust. http://www.experimentalexhaust.com/
              A person puts down a deposit that gets the flanges and mock up parts. We had to get a couple more fittings but happy with the process. A builder mocks it up the way they want and then send it to Experimental Exhaust. They construct it to the mock and it comes back a perfect fit in 321SS. The deposit for the mock up is credited to the exhaust construction. They do great work.

              000_0013.jpg000_0005.jpg
              Attached Files
              Last edited by Glenn Patterson; 07-08-2018, 02:48 AM.

              Comment


              • #8
                Great pictures Glenn..... so the parts with the bigger tubes and the isolators is the 337 part and the tubes that connect it to the BH Fuse
                are the fabbed parts....... that doesnt look too hard. That deal with the wood plugs and the string looks like a great way to assure its in the
                correct place and the correct angle.

                When you decided on an engine---- was an O-470 a competitor with the 360 ? or did the 360 win out by being 100 lbs lighter and only
                20-30 hp less ????? Is there also a heavy and light case on the O-360 like the 470 ?????

                I will try to call the companny that was running the 2 flipped 337's and see if I can determine their status.... they have several 337's
                so they may buy them back from the insurance co. for future use..... but it cant hurt to ask......

                Tim
                PS - I expect to fab my own exhaust since I love to weld.....

                Comment


                • #9
                  The IO-360 was in our backyard and our mechanic friends at the airport said that they were good engines. We had lofty ideas at the beginning. The engine is a 210hp and Continental will dyno at 210 hp. The 3 into I header exhaust should give about 6 hp. We had our names on the list for the time that E-mag were to come out with their 6 cylinder version of self powered electronic ignitions to replace the mags. The electronic ignition gives 5-6% hp gain by improving efficiency and variable timing that would be about 12 hp. We thought that we could get about about 225 -228 hp w/ efficiency gains that is decent power with 100 lbs less. That is the lower end of HP for the 470 or 540 without the weight. I was looking through the invoices and the cost for the exhaust was $1321. Bob in the picture above is a Red Seal welder who did all our TIG welding. We have a Lincoln 225 precision TIG & we could have done our own exhaust. A person could do their own mock up and build it from their mock up. Cheaper to throw plastic than to waste stainless. Here is a helpful homemade tool to bookmark as it could help with the fabricating. https://www.jalopyjournal.com/forum/...-bends.993838/ I have a 40 Ford project that I have to get to that's why I have the HAMB tech on the exhaust cutting jig in the files.

                  The 6 cylinder engine starts quick, runs smooth and is reasonably quiet. The Continental IO's are clean as all the fuel air induction is on top and not in the hot air under the engine. Cooler the air in the better. We extended the new baffles to seal tight to the underside of the cowl to keep the air pressure even over the engine, ducted the openings in the nosebowl to project the air into the space over the engine, put the tear drop lip on the air exit on the firewall and kept a good open channel under the engine for the cooling air to exit. I narrowed the air inlets to put the fuel pump and lines behind the nose bowl. I was told not to worry about the air going in but to focus on getting the air out. We did all we could to avoid the angle lip on the air exits that causes crazy drag. So far the engine stays in the green and cooling does not appear to be an issue.

                  The O-470's were sort of on our radar. A couple members of our flying club had the O-470 in their airplanes. One was owned by an AME/commercial pilot that was well past its TBO. That engine started and ran as smooth as a Swiss watch. Ray knows how to operate an engine to get a good life out of it. Originally were thinking of going with a Barrows 540 as he seems to build them for reasonable money.

                  Correct. The larger frame with the isolators is the 337 mount. You are right in that it was a fairly easy to adapt to the BH. We bolted the ferrules at the attach points, set the engine on the thrust line then fish mouthed the tubes the same as the fuselage. I used the router with the circle cutting base to make the engine plugs. The PDF in this shows the router base to cut the plugs. We used it a lot in our build. Even made plywood wheels to roll the fuselage in the shop. https://bearhawkforums.com/forum/too...hawk-jigs-dies. We have the fiberglass female mold for the lower half of the modified MC-3 nosebowl if you were to need that one day.

                  Comment


                  • Glenn Patterson
                    Glenn Patterson commented
                    Editing a comment
                    Our engine is the IO-360G that is fairly common. IO-360K or KB has a slightly heavier crank. There are STC's for the IO-360 engines used on Stinson 108's. Cessna 170s and 172 that use the regular engines. One AME that I spoke to had an 86 inch prop and another had done some conversions that had done an 86 inch prop. I went the the McCauley application guide and trolled through all the options on the C203 version is common on continentals in Cessnas etc and went 82 inch on the certified aircraft. The PPonk speed calculator showed that the 84 was just under Mach1 for tip speed and an optimum length. So far it seems to be working as expected. The prop is a 2A34C203-BC if you wish to Google and see how common they are. They are a long 2 blade good for a utility or bush plane.
                    Last edited by Glenn Patterson; 07-09-2018, 10:27 PM.
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