Author Topic: Hate to make another no spark thread but I'm at my wit's end.  (Read 2168 times)

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Offline JamesM

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Hey guys, almost done with my CB750 build. Just got it all wired up and I am getting no spark.

I have a Dyna S ignition, dyna 3 ohm coils, brand new reg/rec, and a three position keyed ignition switch.

My headlight (hi and low), taillight (and brake light), speedo light, and horn are all working.

I'm running kick only.

I've done a voltage drop test, tried using each stud on the ignition switch, checked through all of my wiring, I just can't find something wrong and it's driving me nuts. I want to ride this thing.

Any help is appreciated.
Current Stable:

1972 CB750
1973 Shovel
1978 CB750
1977 KZ750T
1996 Shadow VLX

Offline jamesbekman

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #1 on: May 14, 2013, 07:01:42 AM »
So you have 12v power to the coils when you turn your engine kill switch to On, correct?  12v power to the coils is Off when its switched off?

You have set your points and have done the static timing with a test light? 




Offline lucky

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #2 on: May 14, 2013, 08:49:34 AM »
Hey guys, almost done with my CB750 build. Just got it all wired up and I am getting no spark.

I have a Dyna S ignition, dyna 3 ohm coils, brand new reg/rec, and a three position keyed ignition switch.

My headlight (hi and low), taillight (and brake light), speedo light, and horn are all working.

I'm running kick only.

I've done a voltage drop test, tried using each stud on the ignition switch, checked through all of my wiring, I just can't find something wrong and it's driving me nuts. I want to ride this thing.

Any help is appreciated.

Head lights and tail lights have nothing to do with the ignition.

Do you have a volt ohm meter?

Offline jason41987

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #3 on: May 14, 2013, 09:33:12 AM »
did you double check your coils, make sure they are good and you didnt receive a bad batch... spark plugs, spark plug caps... and you verified you are in fact receiving power to the points system with the ignition on?...

something i did to diagnose the ignition system was wire it directly to the battery to bypass the ignition switches, relays, etc just to verify the ignition system itself works... also, you could use a multimeter to verify the points themselves are putting out voltage to the coils when you kick it.. if so, then itll probably be a timing issue

Offline Duke McDukiedook

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #4 on: May 14, 2013, 12:06:25 PM »
Are you sure the kill switch is not fried?
"Well, Mr. Carpetbagger. We got somethin' in this territory called the Missouri boat ride."   Josey Wales

"It's Baltimore, gentlemen. The gods will not save you." Ervin Burrell

CB750 K3 crat | (2) 1986 VFR750F

bollingball

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #5 on: May 14, 2013, 01:28:26 PM »
Just check to see if you do in fact have 12vdc on the black/white wire at the coils. .
Ken

Offline Xnavylfr

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #6 on: May 14, 2013, 06:42:43 PM »
HERE YOU GO!!!

http://www.dynaonline.com/skins/downloads/Default.aspx

The power wire from your DYNA module HAS to be hooked to a switched wire so power comes on to the module when you turn on the key . The directions say to hook the module wire to the Black/white wire going to the coils. If you don't have power to the B/W wire to the coils then you have lost power somewhere ==KILL switch?????


Xnavylfr(CHUCK)


Xnavylfr(CHUCK)

Offline JamesM

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #7 on: May 15, 2013, 05:22:59 PM »
Hey guys, almost done with my CB750 build. Just got it all wired up and I am getting no spark.

I have a Dyna S ignition, dyna 3 ohm coils, brand new reg/rec, and a three position keyed ignition switch.

My headlight (hi and low), taillight (and brake light), speedo light, and horn are all working.

I'm running kick only.

I've done a voltage drop test, tried using each stud on the ignition switch, checked through all of my wiring, I just can't find something wrong and it's driving me nuts. I want to ride this thing.

Any help is appreciated.

Head lights and tail lights have nothing to do with the ignition.

Do you have a volt ohm meter?

Dude, obviously they have nothing to do with the ignition. I was just stating everything else is working to rule out the keyed ignition witch or the reg/rec.

Yes I have a DVOM.

I'm not running a kill switch.

I'll check for at the wires running into the coils again tomorrow.

The coils worked when I tore the bike apart a few months ago... it ran fine. I did a simplified wiring harness on it.

Can I do a voltage drop to my ignition?

I have a wire from the ignition to the same post on the ignition switch as the wires going to the coils to come on with the key turned on.
Current Stable:

1972 CB750
1973 Shovel
1978 CB750
1977 KZ750T
1996 Shadow VLX

Offline sethdhawkins

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #8 on: May 16, 2013, 10:06:01 AM »
As others said, jump power directly to the coils. It's the fastest way to determine if you made a mis-step in your wiring of the coils. If you don't have power then, check the grounding of the coils (do you have new paint?). Make sure you have a ground strap between engine and frame, as this will make your life miserable if its missing. Finally, be really sure that your reg/rect is working properly once you fire it up. The stock regulator on my CB750F fried my Dyna in an hour of riding, with high voltage.
« Last Edit: May 16, 2013, 10:12:52 AM by sethdhawkins »
All a man needs in this world is someone to love, if you can't give him that, give him hope, if you can't give him hope...just give him something to do!

1972-ish CB750K
1974 CB450
1974 CB360
1976 136' Ocean Going Tug

bollingball

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #9 on: May 16, 2013, 11:10:31 AM »
As others said, jump power directly to the coils. It's the fastest way to determine if you made a mis-step in your wiring of the coils. If you don't have power then, check the grounding of the coils (do you have new paint?). Make sure you have a ground strap between engine and frame, as this will make your life miserable if its missing. Finally, be really sure that your reg/rect is working properly once you fire it up. The stock regulator on my CB750F fried my Dyna in an hour of riding, with high voltage.

I don't think the coils need or have a ground. They should fire even if they are not mounted to the bike. The ground would be the spark plug threads.
You might see a harness ground under the coils but it has nothing to do with the coils. It is just a place Honda picked.

Correct me if I'm wrong
Ken ;)

Offline Vinhead1957

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #10 on: May 16, 2013, 11:47:36 AM »
There is a ground for the mount. The frame is unpainted where it mounts. Unbolt it clean the bare spot dielectric grease reinstall

Offline sethdhawkins

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #11 on: May 16, 2013, 11:47:58 AM »
You are correct. I was thinking about the 350/360 twins that need grounding for the condensers, located at the coils. Good catch.

Seth
All a man needs in this world is someone to love, if you can't give him that, give him hope, if you can't give him hope...just give him something to do!

1972-ish CB750K
1974 CB450
1974 CB360
1976 136' Ocean Going Tug

bollingball

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #12 on: May 16, 2013, 03:09:40 PM »
There is a ground for the mount. The frame is unpainted where it mounts. Unbolt it clean the bare spot dielectric grease reinstall

Not sure what you mean here Vin. Do you think the mount needs a ground?

Ken

Offline Vinhead1957

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #13 on: May 16, 2013, 03:34:35 PM »
No the mount itself hits the frame on an unpainted surface. That is frame ground

Offline JamesM

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #14 on: May 26, 2013, 08:13:31 AM »
Hey guys, it ended up being my Dyna S igntion plate being friend some how. It read .37 ohms of resistance, and the new one zeros out.

Threw the new one in, and she fired right up!

Thanks for the ideas and help guys, appreciate it.

-James
Current Stable:

1972 CB750
1973 Shovel
1978 CB750
1977 KZ750T
1996 Shadow VLX

Offline lucky

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #15 on: May 26, 2013, 11:53:38 AM »
Hey guys, almost done with my CB750 build. Just got it all wired up and I am getting no spark.

I have a Dyna S ignition, dyna 3 ohm coils, brand new reg/rec, and a three position keyed ignition switch.

My headlight (hi and low), taillight (and brake light), speedo light, and horn are all working.

I'm running kick only.

I've done a voltage drop test, tried using each stud on the ignition switch, checked through all of my wiring, I just can't find something wrong and it's driving me nuts. I want to ride this thing.

Any help is appreciated.

Head lights and tail lights have nothing to do with the ignition.

Do you have a volt ohm meter?

Dude, obviously they have nothing to do with the ignition. I was just stating everything else is working to rule out the keyed ignition witch or the reg/rec.

Yes I have a DVOM.

I'm not running a kill switch.

I'll check for at the wires running into the coils again tomorrow.

The coils worked when I tore the bike apart a few months ago... it ran fine. I did a simplified wiring harness on it.

Can I do a voltage drop to my ignition?

I have a wire from the ignition to the same post on the ignition switch as the wires going to the coils to come on with the key turned on.

Why do you want to keep doing a voltage drop test?


You just need to get 12 volts to the coils.
Thats all.

If you have to.... just run a wire from the battery straight to the coils for a test.

bollingball

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Re: Hate to make another no spark thread but I'm at my wit's end.
« Reply #16 on: May 26, 2013, 02:47:22 PM »
Hey guys, it ended up being my Dyna S igntion plate being friend some how. It read .37 ohms of resistance, and the new one zeros out.

Threw the new one in, and she fired right up!

Thanks for the ideas and help guys, appreciate it.

-James

Your Dana-s befriended you ;D ;D