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  1. Brian Rupnow

    Upshur's opposed twin engine

    My weed whacker runs---it's the other end that has something gone wrong. I could fix it---but---at 77 years old, I choose my battles carefully. I play with small engines as a hobby because I like to. I don't do maintenance on my car or truck, nor on my gardening equipment. I could--but thank the...
  2. Brian Rupnow

    Upshur's opposed twin engine

    Now isn't that a beautiful thing!!! The new flywheel and hub fit into place exactly as I had expected, and cover up the ignition points. I still have to figure out where I am going to put the condenser, but that can be tomorrows work. Today I have been fighting with horrible weed eater...
  3. Brian Rupnow

    Upshur's opposed twin engine

    So, here we are with the ignition cam and the purchased point set mounted on the flywheel side of the engine. The flywheel shape will change, so that an extended outer diameter will cover the ignition points so that they won't be visible when all is assembled. Please note that the engine hasn't...
  4. Brian Rupnow

    Upshur's opposed twin engine

    No George--Not on this engine with dual cylinders. The points operate off the crankshaft no matter which side they are on. The points open every time the crank rotates thru 360 degrees. The distributor selects which cylinder the spark is going to.----Brian
  5. Brian Rupnow

    Upshur's opposed twin engine

    I'm doubting my ability to successfully solder ignition points onto the brass strip as per the engine plans. However-- If I move the flywheel out farther away from the side of the crankcase and switch the ignition cam to the other side of the engine, there is lots of room for my purchased Dodge...
  6. Brian Rupnow

    Upshur's opposed twin engine

    Thanks for the link Werowance--That is a great running engine.---Brian
  7. Brian Rupnow

    Upshur's opposed twin engine

    Werowance--I have a set of store bought points that have been damaged, but the contact buttons on them are brand new. I would like to unsolder the contact buttons from their original point set and re-solder them to my brass strips and bolt head as per the Upshur plans. What kind of solder did...
  8. Brian Rupnow

    Upshur's opposed twin engine

    After a couple of days of "sluffing off" (which I enjoyed very much), I went back to work on the engine today. The valves had to all be reground to match the new valve cages. I was able to get a drill in thru the exhaust tubes to drill exhaust ports in the side of the new exhaust valve cages...
  9. Brian Rupnow

    Upshur's opposed twin engine

    Cylinder heads have been re-bored to accept new full length valve guides. New valve guides have been fabricated and installed in cylinders after being coated of J.B. Weld. The new threaded insert I made for the sparkplug is installed in the cylinder head, and seems to work fine. Everything I...
  10. Brian Rupnow

    Upshur's opposed twin engine

    I've ran into a problem here with how well my valves seal---or not. Every previous engine I have built used full length "valve cages" in which the valve guide section and the sealing face were all turned from one piece of brass. This engine is designed differently, whereby the valve guides are...
  11. Brian Rupnow

    Plan to build....steam!!

    Do a web search for Elmer Verbourg. He designed a whole bunch of different simple steam engines and most of his designs are available.----Brian
  12. Brian Rupnow

    Upshur's opposed twin engine

    Okay, for what it's worth---The new threaded insert is in place. In the picture you can see a "driver" that I used to screw the insert into place after the aluminum cylinder head was threaded 3/8"-16 and the home made threaded insert was coated with J.B. Weld. Then the driver was unscrewed...
  13. Brian Rupnow

    Upshur's opposed twin engine

    The sparkplug thread repair is under way. What you are looking at is a piece of steel threaded 3/8"-16 unc on the outer diameter and 1/4"-32 on the inside diameter. The sparkplug screws into it just fine. Now the question is "Will I be able to tap a 3/8"-16 unc thread into the aluminum cylinder...
  14. Brian Rupnow

    Upshur's opposed twin engine

    I can get gas into my gas tank, and I can get gas out again. Thats all, to nice outside to spend any more time in my shop today.!!!
  15. Brian Rupnow

    Upshur's opposed twin engine

    Steamchick--I have very little going on in the rest of my life. I spend my time either reading for entertainment or working in my shop.---and occasionally taking good wife out for a meal.---Brian
  16. Brian Rupnow

    Upshur's opposed twin engine

    Today, the engine sub base became a gas tank. Not a lot to say about it---a lot of hogging out on the mill, a cover plate drilled and counterbored to fit, and a bead of J.B. Weld all around before the screws were tightened up.
  17. Brian Rupnow

    Upshur's opposed twin engine

    Today I made the nylon points mounting block, the brass ignition points mounting assembly, the ignition cam and opened up a few clearance holes on the main crankcase assembly. It's a beautiful day here in Ontario, bright sun and 70 degrees F. Wife and I went to a take out restaurant and then...
  18. Brian Rupnow

    Upshur's opposed twin engine

    Yowzah!!!--I rooted around in my plate stock and found a sheet of 0.030" brass plate. That will do to make my ignition points arm and the piece that attaches to the ignition rotor. I have enough black nylon left to make the block that holds the other side of the ignition points. I need to make...
  19. Brian Rupnow

    Upshur's opposed twin engine

    One thing for sure, for sure. I'ts a heck of a lot easier to make cams with flat flanks.
  20. Brian Rupnow

    Upshur's opposed twin engine

    Today I will take a crack at making the cams for this engine. These cams do not have a curved flank, so they should be easier to make. I have attached a sketch of the finished cams which will be made from 01 steel and hardened. Lucky for me, I have a piece of 1/2" diameter 01 material on hand.
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