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Did anybody check out that "sleeve valve???" engine in the back of the white pick up

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  • #16
    Re: Did anybody check out that "sleeve valve???" engine in the back of the white pick

    Originally posted by bruce lockwood View Post
    Another benefit of the design allowed for a cleaner combustion chamber shape (No Valves, better centralization of spark plugs) thus allowing more boost/HP for any given octane rating. The engine will make more HP on 100/130 than the R3350 will. It also get better fuel efficiency. Bruce
    Seems they run more smoothly and quietly too but can use more oil at some settings, if memory serves.

    $
    "Man was meant to fly -- the earth is for worms!"
    Martin Caidin

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    • #17
      Re: Did anybody check out that "sleeve valve???" engine in the back of the white pick

      Split s, I always thought it felt like an R2800 with high compression pistons, hot cams and headers, if you get what I mean.

      I loved how they sounded and felt at around 1100 rpm. They would make a sort of "Ruummp...Ruummp...Ruummp" sound that had the whole airplane rocking and dancing from side to side. You rarely see one of the original Furys these days, but they are pure music.

      Oil consumption was up to 2.5-3 gal per hour on the one I flew. That was due to worn sleeves and tired piston/rings.

      A beautiful engine, but very difficult to do anything with the sleeves. Dave Cornell and I worked with Bill Jones at Aircraft Cylinder for over a year trying to come up with an overhaul procedure for them, but finally gave up.

      The idea was to bore the liners to clean up the rust pitting, then apply .004-.006 of cermichrome thus bring them back to the original standard Dia. There were no over-sized pistons/rings available so this was the only option for overhauling the sleeves.

      We immediately ran into problems as we tried to cut into the original Nitrided interior bore of the sleeves. The original nitriding depth was around .014 with the hardest area nearest the interior surface of the sleeve but progressively softened as you went deeper and there in lay the crux our 1st problem.

      With 1000 hrs or so of time on the engine, the piston thrust load (90 degrees from the piston pin) wore into the sleeves slightly which made them out of round by .002-.003. The out or round area was also softer thus the hone would cut more in that area which only exacerbated the problem.

      The second issue was that anytime material was removed from the sleeve, it would "stress relieve" itself over a 12 hour period and be out of round when it was remeasured a day or two later. One time Cornell cut 0.005" out of a sleeve and it measured perfectly round, by the next day it was 0.025" out of round. He finally reverted to cutting 0.001" at a time as he cycled through 18 sleeves. We started the project with 18 junk sleeves (didn't want to wreck good stuff) but ended up with 18 out of round paper weights when all was said and done. After a year we finally gave up on the project.

      In all we tried a conventional Sunnen boring fixture and hones, then after that failed, we custom built diamond faced honing stones, next a leather strap hone with diamond dust and grease and finally we tried a combination of the aforementioned methods in centerless grinder, nothing seemed to work

      After much research we found that Bristol had dealt with the same issues. They cured the out of round sleeves with a very special 500 ton precision roller thus forcing the sleeves back to round. Cheers Bruce

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      • #18
        Re: Did anybody check out that "sleeve valve???" engine in the back of the white pick

        Thank you A LOT Bruce. I love this kind of explanation, because they show the details of the issues that you guys have to deal with for the passion of air racing, while we, the breed of fans, are hungry of these stuff, and scarcely imagine the hard work that it is behind a sleeve valve.
        I do understand you quite well. Thank you again

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        • #19
          Re: Did anybody check out that "sleeve valve???" engine in the back of the white pick

          ... if you get what I mean.
          Duuuuuuuuuuuuhhh ...

          Thanks for all that, Mr. L. About 45% of that stuck to me, but thanks.

          Wasn't someone squawking about the cost-effectiveness of manufacturing new Merlins being better than that of evolving to a field of turboprop Unlimiteds? If it was feasible to make new mills, why not sleeve-valve radials and their parts?

          $
          "Man was meant to fly -- the earth is for worms!"
          Martin Caidin

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          • #20
            Re: Did anybody check out that "sleeve valve???" engine in the back of the white pick

            I don't think any tooling still exist to manufacture new V-1650 parts, so I would assume the investment just in the machine tools large enough to do the job would be outrageous, especially since only unlimited racers, some aircraft restorers and perhaps the Hydroplane folk could make use of them. They'd be impractical for any other uses with more reliable turbines available.

            It would be nice if someone could come up with an alll-new and more reliable Merlin-sized mill, but with companies like GM spending up to a billion bucks to develop new V-8 car engines, imagine what it would cost to develop a new monster V-12...And the car manufacturers can sell massive numbers of cars to recoup some if not all the engine investment eventually. An all-new monster V-12 using modern tech never could pull that off. Aircraft buyers of large birds want turbines.

            Speaking of hydros, I heard that the surplus turbines they like to use are also becoming scarce now, and are re-considering going back to recips. Anyone else hear about this?

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            • #21
              Re: Did anybody check out that "sleeve valve???" engine in the back of the white pick

              Originally posted by BUD_XXX View Post
              The claim that you get less valve float...at the cost of all this "stuff" whizzing and whiring around.......seems less than desirable.....hence it's demise and lack of current manufacturing....I suppose....

              Anyways, good job folks!
              Actually, none of that seemed to be much of a problem in practice. For Bristol, anyway. Napier had a devil of a time getting the sleeve valves to work right on the Sabre, and IIRC the British government basically stepped in and got Bristol to help get the Sabre working.

              Anyway, I digress. The Centaurus and Hercules had long and successful careers, and when all is said and done sleeve valves aren't *that* much more complicated than getting poppet valves to work on a radial. Remember that on a radial the cam "ring" has to work lots of valves, the crankshaft has to pass through it, it has its own less-than-simple gear train to drive it, poppet valves require 2 pushrod tubes and 2 rocker boxes per jug, gotta get oil up to the rocker boxes, back down to the case (or down and back up for the bottom half of the engine), and gotta keep it sealed inside all the extra little seals that requires, etc. etc. And on top of all that, a sleeve-valve engine allows a tighter-fitting (sleeker) cowl.

              The reasons, as I understand it, that re-engining Sea Furies with R-3350s became popular are 1) the 3350 is much more common, especially in the US, 2) more overhaul facilities are comfortable with the 3350 and the parts supply is better, and 3) sleeve valves didn't work so well when you started running race power.

              Think about #3- all the coefficients of expansion have to be JUST right, because you can't have the sleeve expand too little or it will seize to the piston. If it expands too much, it'll seize to the jug. And all the combustion heat has to flow through the sleeve, to the jug, and out to the cooling fins.
              Last edited by 440_Magnum; 11-02-2009, 01:28 PM.

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