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Mike OBryan

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About Mike OBryan

  • Birthday 11/03/1984

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    Chadron, Nebraska

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  1. I talked to a magneto expert and he said either the magnet or the coil or both are the culprit.
  2. Well the war is over and although I came out victorious I still feel like a loser. All I had to do was close the gap on the spark plugs to about half of what they should be. I know this isn't a permanent fix, I'll need to send in the mag to be serviced. Boy she starts like a new machine tho, hand crank no problem! Thanks for all the support!
  3. Well I hooked a welder up to my magnet charger and got that magnet charged pretty good. That magneto has a real nice hot spark that will draw out two about 5/8". Put it back together today and I'm back where I was before with no fire at all. Spark plugs are sparking nice and hot, timing is the same as before. Driving me crazy! I'm going to see if I can get a guy I know to come look at it, see if he notices anything I'm not. I'll let you know if I make any headway.
  4. James, it looked like that snubber ring is a component of the E4A mag coupling, not the F series. I took the mag off and put it on the bench, I don't believe there's any problem with the impulse coupling. I hooked up all the plugs to a spark jig and ran it at different RPMs and there is a spot at low rpm where there is intermittent spark. Do you think this could be from a weak magnet? I built a magnet charger to do this and it's not all that considerably powerful. Although I went from a magnet that could not hold itself up sideways on the toolbox to one than can I would guess it's strength is 5 lbs or less.
  5. Yeah I might check that snubber ring. Although it doesn't seem to be tripping early it is a pretty loud thud when it does. I think I'll work on it tomorrow, I've got that new condenser too. Thanks for all your help
  6. Ok, well then it checks out, I assumed the the other marks were for the other pistons TDC. DC1&6 marks line up when the impulse trips. Here's the instructions out of my book.
  7. My TD18 manual says go rotate the breaker cover all the way up before you take it off, but from the normal position with the timing link it's almost all the way up anyway so there is very little change by doing this. Not near as much as the action of the impulse coupler by comparison. Maybe it's enough to make a difference i don't know. Also I have two TD 18 manuals and they both say the same thing for the f6 mag. And when I'm verifying the impulse trip I was questioning the marks on the flywheel. The marks are PP 3&4 and PP 2&5. Are these not dead center marks? I thought I saw somewhere that stands for positive pressure or something? The way that I'm getting zero spark at low rpm has me looking back at the magneto for a problem other than the timing to the engine. I'm going to take a couple days off of working on it. Also I have a new condenser coming for the mag, the one I had I don't know if it's actually good or not.
  8. Was able to find the international manual for magnetos. Might find a solution in there when I read it. http://farmallcub.com/rudi_cub/www.cleancomputes.com/Cub/Blue Ribbon Service Manuals/GSS-5035 Service Manual Magnetos/index.html
  9. James, I'll add a picture of the mag serial number. As far as I can tell it's the original mag but I don't know. It looks like an F6 in the book. I set the timing precisely as the procedure in the book states. Which is this basically; -------------- Remove spark plugs from #1 and find TDC by feeling for compression, continue to crank engine until DC 1-6 mark on flywheel lines up with pointer. Disengage the impulse coupling and rotate the magneto to the #1 position. Remove the breaker point cover after fully retarding the timing. Rotate the magneto until the breaker points just start to open and then put the bolts in the coupling. Replace the timing link on the breaker point cover ---------- The timing has had me puzzled and I have suspected something is off, here's why. When I set timing per manual instructions then check impulse trips at each cylinder, the mark on the flywheel rotates by quite a ways before it trips. The manual says the mark should never be above the pointer when the impulse trips but it does. Marks 2-5 and 3-4 go past the pointer quite a bit. 1-6 land closer to the pointer. At one point lately I tried setting the timing so the impulse was tripping when flywheel marks were at or below the pointer as the book says. I did not have any successful firing but perhaps there was another issue preventing any firing at that time. There are a couple marks, one on the impulse coupling and one on the part that you bolt it to. These were there before my time and when I follow the timing procedure they line up. And they were lined up before I took the mag off the first time so it seems to be the timing that was used previously. Something that comes to mind now as I write this is that when my Dad first got this machine 8 or so years ago I remember him mentioning something about magneto work. Perhaps finding a new one, I don't know what it was for sure. He passed away 5 years ago so I can't ask him what it was. I would suspect he had the magneto off at one time tho. Thanks
  10. Yeah something just isn't right. I don't believe I'm getting a consistent spark. Fires good right away a few times, RPMs come up enough that you don't hear the impulse coupling snap and no fire. As soon as the impulse coupling snaps again it fires. When I finally managed to get it running it runs great, there's just like a dead spark area at low rpm. There's gotta be something wrong. I probably should get new plug wires too, these are oldies.
  11. Well she started. I tried different point gaps and nothing seemed better than around .20 so I left it there. Seems to be back to normal. I don't know if they're all like this where it's hard to get past that low rpm firing, this is the only one old crawler I've been around. I think you just have to feather the choke to get over that hump. After my phone charges I'll put up a full video from start to change over. Mike
  12. Ok. After a different condenser, polishing the points and setting them and various gaps It is firing good while the impulse coupler is engaged. Once the rpms come up enough the impulse coupler drops out then it doesn't want to fire. Perhaps it is firing but too soon, I cannot tell. This is more how it usually acts, always hard to get going after slow rpm firing. There's probably something I'm missing that one of you can identify. Here is a video link. https://youtu.be/tY0_U6DPS-Y Thanks for the help Mike
  13. Good food for thought Ken. Might be worth trying a different condenser. It almost had to be something like that since no cylinders are firing.
  14. Thanks Vic, I've checked the timing and plug wires multiple times.
  15. Guys I've got a TD18 built in 49, it's in good condition. Last fall I parked it and pulled the engine clutch out for a rebuild and now I cannot get it to for fire on gas. I'm getting fuel and spark, it doesn't make sense. I charged the magneto magnet, double checked the timing, took the manifold off and checked the butterfly dampers. While the manifold was off I taped the main intake ports shut and tried a little either directly in the lower ports, still no fire. Cleaned the plugs which are almost new, gapped them also. This thing has always seemed to not like to fire on gas very well and I've always suspected a weak magneto magnet but that's ruled out now. Also magneto has a new condenser and points. I'm at a loss and don't know what else to check, please help! Thanks, Mike
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