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  1. #526

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    RE: UMS Evolution Radial Care and Operation

    We'll have to wait a while the more parts UMS / EVO radial engine.
    Horizon told me
    Lars, most of the main parts for this engine isreserved for our service department. If you need a major component it would bebest to send the engine to our repair team and have them fix it

  2. #527
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    RE: UMS Evolution Radial Care and Operation

    Slskn,

    Very timely, your post on the lost pushrods. I just took delivery last night of my 77cc Evolution. My RC'er son noticed the pushrods seemed to be a little looser than we're used to seeing on a typical Saito 150, for example. So, I made a mental note to check the valve lash before the first run. And then I saw your post about your missing pushrod. So, here's a question, after you did the FIRST recommended valve clearance adjustment, was there too much lash? If so, I'd expect the pushrod loosening to continue for a whle but at a much less agressive rate. But, 20 flights might be quite enough time, even at a reduced rate, for enough loosening to have occured. Check your head bolts, too.

    I hope I'm right about this, but since aluminum expands at a faster rate than steel, the crankcase and cylinders, at temperatuare, are going to grow (expand) more than the pushrods. So whatever the valve clearance (lash) is cold, seems like it would get worse at running temperature.

    Again, anyone seen an exploded parts list and diagram of this engine (Evolution 77cc)?

    Here are some more pictures of my home-made exhaust ring project. You'll recall I found a "copper" ornamental sprinkler whose inner hoop seemed about right to construct an exhaust ring. I think it will work, here are some progress pictures. I was surprised to find out the hoop is not copper, but copper plated stainless steel. It's non-magnetic. It's ok though, I know I can braze stainless steel. I'm just glad it didn't turn out to be aluminum!
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  3. #528

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    RE: UMS Evolution Radial Care and Operation


    ORIGINAL: Pull Up Now!

    Slskn,

    Very timely, your post on the lost pushrods. I just took delivery last night of my 77cc Evolution. My RC'er son noticed the pushrods seemed to be a little looser than we're used to seeing on a typical Saito 150, for example. So, I made a mental note to check the valve lash before the first run. And then I saw your post about your missing pushrod. So, here's a question, after you did the FIRST recommended valve clearance adjustment, was there too much lash? If so, I'd expect the pushrod loosening to continue for a whle but at a much less agressive rate. But, 20 flights might be quite enough time, even at a reduced rate, for enough loosening to have occured. Check your head bolts, too.

    I hope I'm right about this, but since aluminum expands at a faster rate than steel, the crankcase and cylinders, at temperatuare, are going to grow (expand) more than the pushrods. So whatever the valve clearance (lash) is cold, seems like it would get worse at running temperature.

    Again, anyone seen an exploded parts list and diagram of this engine (Evolution 77cc)?

    Here are some more pictures of my home-made exhaust ring project. You'll recall I found a ''copper'' ornamental sprinkler whose inner hoop seemed about right to construct an exhaust ring. I think it will work, here are some progress pictures. I was surprised to find out the hoop is not copper, but copper plated stainless steel. It's non-magnetic. It's ok though, I know I can braze stainless steel. I'm just glad it didn't turn out to be aluminum!
    I did the valve adjustment about 5 flights in, but your assumption may be correct about the temp and so on, I just ordered 3 packs of push rods, comes with 2 rods and 2 cam follower pins, per pack for 3.99, I am sending pics of the rods upon inspection today I found 2 more rods with the end toward the rocker arm wore or chipped on the steel end where the rocker pin sets in the cup, the edges around on the sides are wore or chipped not sure how or why this has happened? I am sending pics to Horizon to show and see if there are any reason why this is happening hope the pics come through-Steve
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  4. #529

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    RE: UMS Evolution Radial Care and Operation

    Pull up now, that is a great Idea on the exhaust ring looks like it will work, I am using the Keleo ring and it is a 3 piece unit that clamps together and the connection is right to each cyl. and then tightened with the exhaust nut, I had a little trouble getting mine to fit but loosening the cyl. head was the trick to get it lined up, and then went together after that ,but so far it works well with no leaks or anything coming loose,........ one thing I forgot to mention was the packs of rods are 3.99 ea. anyway, the other thing is on the flights on the Corsair is that I am flying it full throttle almost the entire flight, except when slowing it up for the landing gear and the flap check, then landing, maybe being to hard on the engine at 8 minutes of flying time each flight? when I get the new rods I will re-lash the valves again and see how it goes-Steve

  5. #530
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    RE: UMS Evolution Radial Care and Operation

    Steve (slskn),

    That chipping is scary! Wish I'd have known about this sooner. Honestly, I read forums 'til blue in the face, and never heard of this failure mode. Chipping is from metal that is too hard. That excess hardness comes from two sources, one is failure to draw back (anneal) the metal properly after heat treatment to begin with. Second, is the metal work hardened during use from the constant pounding. I'd say it's 50/50 for now. The only way to know for sure is to do a hardness test on new pins. Anything above a Rockwell 58-60C is too hard, IMHO, for this use. You can do a quickie test with a file on a sacrificial new pin. If you can't file the metal, it's too hard.

    Now, I've looked for spare parts for this engine. I don't remember seeing pushrods. How did you get a part number to order? Did you call Horizon's repair dept?

    By the way, that side wall you showed chipped out will cause the pin to fall out for sure! In flight!

  6. #531

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    RE: UMS Evolution Radial Care and Operation


    ORIGINAL: Pull Up Now!

    Steve (slskn),

    That chipping is scary! Wish I'd have known about this sooner. Honestly, I read forums 'til blue in the face, and never heard of this failure mode. Chipping is from metal that is too hard. That excess hardness comes from two sources, one is failure to draw back (anneal) the metal properly after heat treatment to begin with. Second, is the metal work hardened during use from the constant pounding. I'd say it's 50/50 for now. The only way to know for sure is to do a hardness test on new pins. Anything above a Rockwell 58-60C is too hard, IMHO, for this use. You can do a quickie test with a file on a sacrificial new pin. If you can't file the metal, it's too hard.

    Now, I've looked for spare parts for this engine. I don't remember seeing pushrods. How did you get a part number to order? Did you call Horizon's repair dept?

    By the way, that side wall you showed chipped out will cause the pin to fall out for sure! In flight!
    I did contact the service dept. and sent pics of these rods and they have not heard of this problem either but hopefully they will check this problem out, I am convinced that the rod fell out due to the chipped or wore edges too, should have them by this weekend, and will keep an eye on the rest of the rods, I could try to file one of the old ones after replacing but I may send to Horizon for inspection maybe they can send to manufacturer to see if it can be improved upon? or find out why this has happened? may have been a bad batch of rods? we will see-Steve

  7. #532
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    RE: UMS Evolution Radial Care and Operation

    Well, since Horizon said this is the first time they've heard about this problem, maybe more defects will show up if it's a lot/processing issue. That means a certain number of defective parts went through, but no more. I know the thread probably says somewhere, but I'm not going to re-read just for that info. I can easily see, at UMS's heat treat supplier, someone going to lunch to eat that yellow stuff they eat and forget to anneal a basket of pushrods. You see, it's a two-step process. First you heat and quench quickly. Second, they have to reheat at a lower temperature for a shorter time, and NOT quench. This softens the metal slightly, and maybe that's the step that was omitted. It's really a quality control issue. If UMS has no Incoming Inspection department to verify parts are to spec, they will just pass through and end up on our engines. Years ago, I worked in QC and we had a Rockwell hardness testing machine. Test samples of parts were measured dimensionally, and hardness was tested too, just like any other specification. Anyway, blah blah you get the idea.

    Which EVO radial do you have, anyway, Steve?

  8. #533

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    RE: UMS Evolution Radial Care and Operation

    I do not know of any body else or even a mention of this happening on this thread, but the engine I have is the evo 9-99 cyl., have it on a Ziroli 93in. Corsair ways in at 36lbs. fly`s the plane with authority , but not over powered the engine fits the cowl like a glove, looks cool just hope I can get over this problem, video flights are on this thread earlier-Steve

  9. #534
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    RE: UMS Evolution Radial Care and Operation

    OK, I checked out your videos. Very nice flyer! As for the pushrods, try post #440 on page 18. The guy didn't mention they were chipped, but they did fall out.

  10. #535

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    RE: UMS Evolution Radial Care and Operation

    I've noticed up to .018 thousandsof side to side slop in the end play between the rocker arm & head casting on my 7-77. pretty excessive when you figure the push rod and the rocker shaft are at this angle. If you adjust your valves at the tight end of this tolerance , it will run very loose when the rocker arm travels over to the high , or sloppy side. I'm experimenting with some .015 thousands rocker shaft shims to correct this issue .......meanwhile i better order a couple of pushrods.
    ____________AIRSPEED IS LIFE_____________

  11. #536
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    RE: UMS Evolution Radial Care and Operation

    Pappy, good thought. where are you getting these thin shims?

  12. #537
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    RE: UMS Evolution Radial Care and Operation

    Maxam, I'm intrigued over your not using onboard glow starters with your E777. May I ask what cable connecters you install in your plane to receive the power from your battery pack? I want to make up the battery pack and am not sure of adequate guage wire and plugs to use. Thanks. Jerry

  13. #538

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    RE: UMS Evolution Radial Care and Operation

    I use size N concentric connectors from Radio Shack and 12 to 14 guage wire. The female connector hides well. -Tom

  14. #539
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    RE: UMS Evolution Radial Care and Operation

    For those who are interested, I finished my home made Evolution 77cc exhaust ring, and posted more construction photos to post #527 in this thread.

    Rick

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    RE: UMS Evolution Radial Care and Operation


    ORIGINAL: Pull Up Now!

    Slskn,

    Very timely, your post on the lost pushrods. I just took delivery last night of my 77cc Evolution. My RC'er son noticed the pushrods seemed to be a little looser than we're used to seeing on a typical Saito 150, for example. So, I made a mental note to check the valve lash before the first run. And then I saw your post about your missing pushrod. So, here's a question, after you did the FIRST recommended valve clearance adjustment, was there too much lash? If so, I'd expect the pushrod loosening to continue for a whle but at a much less agressive rate. But, 20 flights might be quite enough time, even at a reduced rate, for enough loosening to have occured. Check your head bolts, too.

    I hope I'm right about this, but since aluminum expands at a faster rate than steel, the crankcase and cylinders, at temperatuare, are going to grow (expand) more than the pushrods. So whatever the valve clearance (lash) is cold, seems like it would get worse at running temperature.

    Again, anyone seen an exploded parts list and diagram of this engine (Evolution 77cc)?

    Here are some more pictures of my home-made exhaust ring project. You'll recall I found a ''copper'' ornamental sprinkler whose inner hoop seemed about right to construct an exhaust ring. I think it will work, here are some progress pictures. I was surprised to find out the hoop is not copper, but copper plated stainless steel. It's non-magnetic. It's ok though, I know I can braze stainless steel. I'm just glad it didn't turn out to be aluminum!
    GREAT LOOKING exhaust ring!!! nice work, just saved your self $190.00 to $250.00 dollars, now how to keep in place? maybe some springs? or something? I am looking to get another radial for a Stearman project thanks for the Idea!-Steve

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    RE: UMS Evolution Radial Care and Operation


    ORIGINAL: Pull Up Now!

    Pappy, good thought. where are you getting these thin shims?
    I'm just making them out of .015 music wire for now in the shape of "c" clips
    I should be testing next wednesday. So far it took out a lot of the valve train slop.
    ____________AIRSPEED IS LIFE_____________

  17. #542
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    RE: UMS Evolution Radial Care and Operation


    ORIGINAL: slskn



    GREAT LOOKING exhaust ring!!! nice work, just saved your self $190.00 to $250.00 dollars, now how to keep in place? maybe some springs? or something? I am looking to get another radial for a Stearman project thanks for the Idea!-Steve

    Thanks for the kind words on my silencer ring efforts. As for how I intend to retain it to the engine, see these photos showing custom made clamps. There are three of them. The sleeve that is brazed to the ring has a slit, which is compressed by the aluminum clamp. It clamps, in turn, to the exhaust outlets that came with the engine.

    By the way, the exhaust ring itself turns out to be non-magnetic 300 series stainless steel! Pretty cool, for cars you pay big bucks for stainlesss steel exhaust.
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  18. #543
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    RE: UMS Evolution Radial Care and Operation

    ORIGINAL: pappy 883


    ORIGINAL: Pull Up Now!

    Pappy, good thought. where are you getting these thin shims?
    I'm just making them out of .015 music wire for now in the shape of ''c'' clips
    I should be testing next wednesday. So far it took out a lot of the valve train slop.
    I just checked my E777 and found a lot of difference in side play of the rocker arms from one head to another. I can also feel the valve clearance grow a little if one forces the rocker to one side. I plan to measure this gap difference and correlate it to rocker side play later this week. 'Will report.


    I'm STILL searching for an appropriate kit or ARF in which to put this engine. It's a little frustrating because none of the manufacturers put the cowl dimensions in their info. DUH. As an engineer, it's a little hard to imagine how a company can put all that effort into designing and marketing a kit, and then not do the detail work in their advertising. I just watched a TBM video on their nice-looking FW190 from ESM where the guy actually SAYS "the big cowl will fit just about any engine, the dimensions are available on our website". Which they're not! How about just picking up a stupid ruler while the camera is running and telling us the dimensions right then and there??? I'm just sayin'!

    Please, guys out there in forum threadsif you talk about your plane, please mention who produces your kit. You'll save a lot of people a lot of time. Thanks in advance. OK OK I'm cranky this morning, I admit it. I did write to Horizon and told then it would be helpful if they compiled a list of kits, and their cowl dimensions, as part of their effort to help people decide to buy their engines.

  19. #544

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    RE: UMS Evolution Radial Care and Operation

    ............. seriously ?
    ____________AIRSPEED IS LIFE_____________

  20. #545

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    RE: UMS Evolution Radial Care and Operation

    I finally found some methanol........life is good.
    The break in can continue tomorrow as scheduled.
    ____________AIRSPEED IS LIFE_____________

  21. #546
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    RE: UMS Evolution Radial Care and Operation

    Currently considering the TF Giant Corsair ARF for my UMS Evolution 77cc radial. I'm a bit hesitant because I know the cowl will be tight. I located a kit, and an ARF at a LHS, so I went to look, take some measurements. The ABS cowl comes in pieces you assemble. It measures a bit over 10" diameter. The ARF version's cowl, which is fiberglass and one piece, was a little smaller. Also unfortunately tapered with draft angle so it would come out of the mold plug. That makes it smaller in front, where all the clearance is needed. So, in the front, by the engine, it was 9 1/4" diameter. So, I went home and simulated that cowl with aluminum sheet metal, as shown in the attached pictures. There is clearance, but the cowl and engine installation will be really critical. I understand the engine has very little vibration, so that should help keep a closely-located cowl in place. Otherwise, this kit, at 25lbs, is about the right weight for the 77cc Evolution. Comments?

    I should mention the Black Horse Models Corsair is a better fit for the engine. But that kit is a lot more expensive, especially if one doesn't want the air retracts that come with it. I wish they offered it without the retracts. That would narrow the price gap a bit. Or at least offered it with some Robart electric retracts.
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  22. #547

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    RE: UMS Evolution Radial Care and Operation

    Rick, That is pretty close and please account for when the valves open.

    There has been concern for side play with the rockers. The force from the rods will keep them in a specific location during operation. When testing for valve gap clearance the rockers will move to the same location. Yes the pushrods have side play but they do work well. I have flown the hell out of these engines and they are still solid. -Tom

  23. #548
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    RE: UMS Evolution Radial Care and Operation


    ORIGINAL: Maxam

    Rick, That is pretty close and please account for when the valves open.

    There has been concern for side play with the rockers. The force from the rods will keep them in a specific location during operation. When testing for valve gap clearance the rockers will move to the same location. Yes the pushrods have side play but they do work well. I have flown the hell out of these engines and they are still solid. -Tom
    Hey, Tom, thanks for the heads up on the valves being open when measuring the diameter. And also for the valve clearance. For the latter, I think the main issue is not during operation, but during adjustment. If the rocker is shifted the wrong way, one could adjust it, only to have it change once the engine turns over.

    More info on the Top Flite Giant Corsair. I took my 77cc Radial in to that LHS to do an actual fit check, engine-to-cowl, with real parts. THEY'D SOLD THE DANG KIT RIGHT AFTER I LEFT YESTERDAY!!!!!! What are the chances....I think it's related to the Model Airplane News article that JUST came out, with the TF Corsair ARF right on the cover. Must have generated some excitement.

    The guy had not picked up the kit yet, though he'd paid for it. He didn't have his truck with him, so I guess it was an impulse buy! Anyway, I got to play with HIS cowl and still do the Evolution fit check. Here are some pics of HIS cowl.

    The engine fits snug, but quite doable. There is at least 1/4" all aroundplenty of room if you know what you're doing. Enjoy the pics of the OTHER GUY'S cowl. heh heh!
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  24. #549

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    RE: UMS Evolution Radial Care and Operation

    Oh yeah you are fine with that clearance. Make absolutely sure that you have good airflow. Radius the front of the firewall on the fuselage to allow more air around the cowl. One problem with the Top Flight is the cowl flaps are barely open restricting flow. -Tom

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    RE: UMS Evolution Radial Care and Operation


    ORIGINAL: Pull Up Now!

    Currently considering the TF Giant Corsair ARF for my UMS Evolution 77cc radial. I'm a bit hesitant because I know the cowl will be tight. I located a kit, and an ARF at a LHS, so I went to look, take some measurements. The ABS cowl comes in pieces you assemble. It measures a bit over 10'' diameter. The ARF version's cowl, which is fiberglass and one piece, was a little smaller. Also unfortunately tapered with draft angle so it would come out of the mold plug. That makes it smaller in front, where all the clearance is needed. So, in the front, by the engine, it was 9 1/4'' diameter. So, I went home and simulated that cowl with aluminum sheet metal, as shown in the attached pictures. There is clearance, but the cowl and engine installation will be really critical. I understand the engine has very little vibration, so that should help keep a closely-located cowl in place. Otherwise, this kit, at 25lbs, is about the right weight for the 77cc Evolution. Comments?

    I should mention the Black Horse Models Corsair is a better fit for the engine. But that kit is a lot more expensive, especially if one doesn't want the air retracts that come with it. I wish they offered it without the retracts. That would narrow the price gap a bit. Or at least offered it with some Robart electric retracts.
    your first cowl looks similar to my 9-99 in my corsair the clearance is about 1/16th 0f an inch with the valve clearance`s just clearing the cowl and I have enough screws to hold it in place so it don`t even budge, however I did have to open the cowl flaps to get the proper air flow. I just got my push rods in and will re adjust the valves tomorrow they look like they have too much gap, maybe that`s why one fell out, but I found two more rods that have been either wore or chipped as I said before I will be sending them back to Horizon so they can inspect them and maybe have an Idea of why they did that, there does seem to be side to side play (maybe more than normal)? in the cup of the rod, hopefully readjusting them will help-Steve


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