No Spark from the plugs after new coils.

Arg, I'm back. Kz 650 "77 modelC

Looked at all the forums and still have reservations on a few things. I've talked to Loudhv, Patton and had a few others sent some advice my way and it's been helpful, but..... I'm running into myself probably. I never have much time but I'm trying to get on the bike lately and here's where I'm at. Ohm checks on the coils primary 4.5, secondary 24k +-. Getting power to from the red/yellow just fine before the coils. Checked all connections, they're good. Harness is intact from before (wrapped tightly) and is good. Took the plugs out and reconnected to the caps, left them hanging and turned the starter, no sparks. Now, if there's something I'm missing 'there', let me know cuz I'm no expert on electrical tests but I can run a volt meter. Dyna was good before getting the new coils and I've gotten thumbs up from Patton that my set up is right (splitter from Dyna etc). I tried last week to get er runnin but she barely kicked and then basically nothing and man I tried. I have 2 points. 1, my coils suck regardless and my dyna is good, or (2) I blew the dyna somehow. I've seen writing here that the ohm test doesn't mean shit and your screwed. That the dyna took a shite and won't feed the coils now. Basically it has come down to the tests. If I follow what dynatek says, I have to turn the ignition on, test inside the caps, etc, and see my reading. Fine, but that goes against what I've read here. By doing that, I'm going to short out the coils, or the dyna, or both! Tomorrow, I'm going to test the dyna per their instructions since I have no choice at this point. Can someone enlighten me on the best way to test the spark plugs while they're connected, and perhaps the best way to test the dyna, I don't really trust the steps dynatek states and skips in their instructions. To add to that, the Dynatek instructions that were sent to me, they didn't even list Dyna2 ignitions and ohm readings on their list. Havin trouble finding dynatek reliable on their instructions. I'm afraid to test as dynatek says, and then find out Loudhvx was right (which I'm sure he is) and blow the coils 'AND' the dyna. Missing something here and I'm a little paranoid about proceeding. Ahhahhahahahhahhhaahha should have studied electrical engineering. Thanks guys, you've all been great.

Uncledirt wrote: "Took the plugs out and reconnected to the caps, left them hanging and turned the starter, no sparks."

If you left them hanging you will not get a spark. In order to get a spark the sparkplug body (i.e. the metal hex section) must be held against the engine or some other ground, otherwise the circuit is not complete. Ed

650ed wrote: Uncledirt wrote: "Took the plugs out and reconnected to the caps, left them hanging and turned the starter, no sparks."

If you left them hanging you will not get a spark. In order to get a spark the sparkplug body (i.e. the metal hex section) must be held against the engine or some other ground, otherwise the circuit is not complete. Ed

And where both spark plugs have been removed, both spark plug bodies must be grounded against the engine. Both spark plugs and the metal engine head are parts of the so-called "secondary loop."



Good Fortune!

There must be some misunderstanding. I don't think I've contradicted any test procedure that Dyna recommends, at least none of the ones I've seen. At least, not in regards to damaging coils.

Some tests are only one way tests. That is they can confirm something is bad, but can't confirm something is good. It's like testing for a leaky tire... If you fill it up and it deflates right away, then you know it's bad, but if you fill it up and it stays inflated for 10 minutes, does that mean the tire has no leak? No, there's just not enough data.

Concerning the Dyna tests damaging the coils. The tests they give should be ok to perform. As Ed and Patton explained, there is a path for the high-tension current, and that path must be complete while testing for spark, or coil damage will occur. It may not be complete shorting, but just a mild decrease in potential spark voltage. This type of damage is much harder to detect as it only shows symptoms under certain conditions. Usually at higher RPMs and at wider throttle openings. Thats when there is a lot of air squeezed into the spark gap, and since air is an insulator, the sparks don't want to arc so it takes more voltage to create the spark. If the coils are mildly damaged, it will result in a misfire.

Now, in the high-tension path, a gap of 1/4" is fine in open air. But you really don't want to exceed 1/2". That's pushing your luck. Since the inline fours have two plugs in the circuit, the total combined gap at both plugs shouldn't really exceed 1/2" during testing for sparks. (Usually you can get 3/4" on new coils and a good igniter, but parts are not cheap so it's best to not take a chance.)

One other word of caution; during the testing, don't leave the ignition powered up for long periods. The way the Dyna S is setup, the coils are drawing full current all the time until a magnet comes by the pickup. If you forget to turn off the ignition, you can overheat the coils and cause heat damage, which can sometimes split the coil open.

Doesn't the Dyna website have downloadable instructions?

Ah thanks for helping guys. Hey Loud, I meant where you said I can get a short in the coil or dyna by turning on the ignition w/o a plug in the caps, and the dynatek inst. says to do that to measure voltage in one of their steps. Anyways, I have spark on both sides. I tested the spark plugs as you guys said, worked fine, lil jolt woke me up:) SO, I started to look at the plugs after starting the bike, wasn't getting gas to the pistons. Fixed that. Tested some connections, spun the dyna around taking readings (not too sure about that test). Made sure all the connections were good and hit her up. Could tell immediately I had fire in a few only. Was real shocked to see it was in 1 and 2?! Only!? WTF, so I know I'm getting spark in 3-4, gettin gas in there, what the hell? Decided to ride her to get some real rpm and more gas in there (did this with the old points and sometimes it worked) sure enough, started getting pipe#3 a little hot. #4 is stone cold still and 3 started choking out toward the end of the short ride. Going over the diagrams and I'm stumped. Basically that says my R/Y wire to both (+) is working for 1&2 only? Can it be a case of plugs, gas, weak spark all together there? This out of parallel suprised me and it's got to be real simple or real complex. How? I don't see the correlation. Here's two diagrams I have. Just for sanities sake I'm posting it, the top is what I have installed, the bottom is from dynatek, see where the splice is made "BEFORE" the R/Y go into the coupler and split? I simply do not know.

Grrrrrrrrr, the posts are upside down. The good drawing is from dynatek, the uglier one is from my existing setup. )

swap the plugs and plug wires on 1 and 4, and the same for 2 and 3. If the problems move, then you know it's wires or plugs (or even maybe the coils). If problems stay in the same cylinders, then it's the carbs or the motor.

If the problems move, then swap plug-wire ports on the coil. If the problems move to other cylinders, then it's the coil. If the problems stay in the same cylinders, then it's the plugs or plug wires.

That "Splice" that comes with the Dyna kit is more trouble than it's worth! Many riders using this sytem have had intermittent operation as it's not a good electrical connection.

The best way is to solder the junction and then cover it with heatshrink tubing, making for a moisture resistant connection.

Yessssssss, it was 1 bad plug and another on the way out. 4 was gone and 3 was intermitant. Thanks to all, especially Mr. Loud:) Switched and played around, #3 kept hangin and confusing me when I was rewiring, found 4 out immediately though. Spun her around the block, sounds good and pulls like she used to. Patton, everyone, thanks, this is a great forum and I hope I can return the favor to someone else on here sometime, I'll be reading! Cheers.