Coil Testing - 18hp briggs and stratton

  1. Welcome to 6x6 World.

    You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!

    If you have any problems with the registration process or your account login, please contact us. Looking forward to seeing you in the forums and talking about AATVs!
+ Reply to Thread
Page 2 of 3 FirstFirst 1 2 3 LastLast
Results 11 to 20 of 22

Thread: Coil Testing - 18hp briggs and stratton

  1. #11
    Join Date
    Jul 2011
    Location
    Kittanning, PA
    Posts
    751
    Pull your fan shroud, the tin work that covers the flywheel. Look at your coils, there will be a wire than runs between BOTH coils, then over to the plastic studd on the tin work. (or there will be a wire that runs between both coils, and then goes somewhere..) Unhook that wire from both coils and see if that helps. Make sure your gap is set correctly, you can use the 3x5 notecard like stated in thee post above. Thats all you need for spark my friend..if you staill aint got spark after youve unhooked that wire, you got bad coils id say, Or bad plugs..Plugs DO go bad..ive seen it numerous times.

    how are you checking for spark?
    I have officially caught the 6-wheel-sickness!!

    "If your gonna be dumb, you better be Tough!"

    "I have done so much, with so little, for so long, that I'm now capable of doing practically anything with virtually nothing...."

    BUY AMERICAN..or...BYE AMERICA!!!

  2. #12
    Join Date
    Jul 2011
    Location
    Kittanning, PA
    Posts
    751
    unless you've only got ONE coil...like racer said, then i'd look at plugs N such. The voltage reg should not have anything to do with it (box with red wire and 2 yellows) Voltage reg creates DC voltage N such for your charging system. Nothing to do with spark. spark is solely controlled by flywheel and coils, via magnets. (unless its a points system...)
    I have officially caught the 6-wheel-sickness!!

    "If your gonna be dumb, you better be Tough!"

    "I have done so much, with so little, for so long, that I'm now capable of doing practically anything with virtually nothing...."

    BUY AMERICAN..or...BYE AMERICA!!!

  3. #13
    Well, The small wire coming off of the coil was the kill switch ground wire. For some reason, the previous owner had it wired to ground (any position the key was at). The small engine place said to remove the wire and see if it sparks. Well, I had the plugs in the motor, unplugged the small wire and it started!! I could not get it stopped, so I touched the small wire from the coil to the engine case, it sparked and stopped. Pul the shrouds back on, ran another wire from the small coil wire to a toggle switch (figured that would ground/unground???) Tried again to start and no spark. unplugged the wire like before and still no spark. WOW, the son and I were excited for a minute then dang. Very frustrating to someone who knows nothing about engines. He was telling me that if I do something wrong at the switch (something, can't remember what he said) it can fry the coil. I'm wondering if that happened. guess I'll take it back to the place and get it tested again.

  4. #14
    Just saw ya'lls post, thanks for the help. Will keep trying I guess. So that stud is plastic, I did not know that, the small wire from the coil was attached to a stud with another wire going to the key switch assembly, that is what i unplugged the first time and it started. Then, no more, LOL.

  5. #15
    Join Date
    Jul 2011
    Location
    Kittanning, PA
    Posts
    751
    well the stud is metal, but it should be encased in plastic? is this a vanguard vtwin 18? or the older opposed (side sitting vtwin) ?

    Mine was intermitent also ragman, sometimes it'd run, others it wouldnt. untill i TOTALLY unhooked wire from both coils, ran new ones to a kill switch, and just looped em together. but once you let us know what motor it is, i think we may be able to help pin point a little better.
    I have officially caught the 6-wheel-sickness!!

    "If your gonna be dumb, you better be Tough!"

    "I have done so much, with so little, for so long, that I'm now capable of doing practically anything with virtually nothing...."

    BUY AMERICAN..or...BYE AMERICA!!!

  6. #16
    I think I read on some site (while looking for the coil) it said "L" engine. It does not look like a "V" twin, I guess opposed like you said. Not a Vanguard according to the sticker on the case. You mean the small wire on the coil that the small engine place said went to the kill switch (ground)? If so, that is when I had it run for a sec (after I disconnected it), then grounded it out on the case to shut down. Then it would not start up again (even with that small wire not touching anything. I think that's what you mean. Thank ya'll guys for sticking with me, LOL. Hard to do over the internet in a forum, LOL. Great to have also, good help here!
    Phil
    Last edited by ragman88; 12-16-2011 at 12:21 PM.

  7. #17
    Went thru all the wiring, The wire from the magneto did connect to the plug on the back of the switch that had the marking "M". I'm guessing that is ok. However, on the back of the switch, there are 5 terminals that go into a plug from the wiring harness. There is a 6th terminal that says "3". It is the ground (as best as I can find on the internet-part of the terminal touches the outside of the plug case). Nothing was connected to this. So, If i'm thinking correctly, even with the wire from the magneto connected to the correct terminal on the switch, with NO chassis ground was connected to the "3" (ground) terminal, a ground was not going to happen, is this correct???? If that is true, could a positive source somehow thru the switch/wiring travel down the wire that connects to the magneto-backfeeding somehow and shorting out the magneto?

    Sorry for the rambling, just trying to figure this thing out LOL. Think I'm in over my head. The small engine place said he really didn't want to mess with it since the wiring harness has been cut/tapped multiple times. I guess could be a headache for him LOL.

    Thanks

    Phil

  8. #18
    Join Date
    Dec 2011
    Location
    Ontario Canada
    Posts
    672
    I am having a similar problem with my kohler k399-2t.
    Only 1 cylinder is firing.
    The box you described is a rectifier that converts ac to dc volts from the magneto behind the flywheel for charging. If you have a magneto type ignition there are points and a primary coil behind the flywheel that sends a spark to the secondary coils on the side of the block and they fire the plugs. Problem could be points, condenser or primary coil.

  9. #19
    Join Date
    Oct 2007
    Location
    statesville, north carolina
    Posts
    2,604
    For some reason the coil on the L head briggs could be really finicky. Try this.... remove the small wire from the back of the magneto, remove the plug wires from the plugs and lay them on the engine so that they are grounded. Grab both with pliers and have someone crank the engine. While its cranking slowly lift the plug wires away from ground. That particular magneto (new ones... the originals didn't) has an internal breaker and sometimes this grounding procedure will reset it. What are the terminals on your ignition switch labeled? The 5 main ones should be : B- battery+, G- ground, M-magneto, L-lights and S-start
    A well regulated Militia, being necessary to the security of a free State, the right of the people to keep and bear Arms, shall not be infringed.

  10. #20
    She's running!!!!! But smoking a lot. Could it be smoking because the oil was half full of gas. when drained, it was approx. 1/2 gas, 1/2 oil. Someone told me that a needle valve or something in the carb was prob. stuck open letting gas drain into the case the last 3 years just sitting. I hope it quits smoking!

    The new problem, it wont go, LOL. It will go forward and backwards, but will not turn. Alway's gonna be something on an old machine I guess till it gets tuned in good.

+ Reply to Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts