Author Topic: Feels like a fuel delivery issue but ISN'T!!  (Read 4273 times)

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Offline Duke McDukiedook

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #25 on: September 20, 2010, 08:05:21 AM »
You never bothered to mention that you tested you coils with an ohmeter. Did you?
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Offline Seafarm

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #26 on: September 20, 2010, 07:07:02 PM »
Not trying to be funny.  Does Dyna have the market cornered?
  I guessing the drawback to drilling holes in the points cover for venting the DYNA, is moisture.?  Assuming high temp is the culprit. 
  Is it possible the Dyna was causing one of the coils to fail and the points won't?  Or is it more likely to be the ignition?
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Offline scottly

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #27 on: September 20, 2010, 08:01:46 PM »
There are other electronic ignitions available. Personally, I wouldn't trust anything that puts the high current switching devices under the points cover, because of the heat. That's just my opinion, after years of working as an electronic tech.
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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #28 on: September 21, 2010, 02:40:21 AM »
There are other electronic ignitions available. Personally, I wouldn't trust anything that puts the high current switching devices under the points cover, because of the heat. That's just my opinion, after years of working as an electronic tech.


Sure, now you share this with us.

Offline Seafarm

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #29 on: September 21, 2010, 01:03:17 PM »
You never bothered to mention that you tested you coils with an ohmeter. Did you?


Ok, so the coil test with ohm meter has been delayed because I didn't know how to do it.  I've done a little studying and I think I've got it.  May I list the steps as I understand them?
Testing Coils
1.  Set the multimeter to the 10 ohm range-touch the leads together and remember the reading.  Subtract it from further readings.

2.  Pull all the spark plug boots and de-screw them from their wires.

 
3. Stick a lead on the yellow wire and the other on the black wire where they meet the coil.    These are the (gozintas) as it were.  Figure the reading. 

4.  Stick one lead in eack of hte spark plug leads.  Figure that one too.

5.  Tell everybody so they can decipher the meaning of the readings. :-*

Am I close?  gonna try it now.


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Offline Seafarm

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #30 on: September 21, 2010, 07:11:21 PM »
Ok.  I'm wrong.  I got a reading off the wires.  1+4 were 14.98 and 2+3 were 14.35.  I couldn't get a reading off  the gozintas.  Is my meter set right?
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Offline Spanner 1

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #31 on: September 21, 2010, 07:45:37 PM »
In my experience on this Forum I have seen lots of folks 'freaking-out' about their coils. Coils, coils, coils and can't remember when I've seen a bad one !!... It's likely always something else IF stock set-up.
Dyna loads the coils with power for far longer ( in a firing cycle ) than points do, so yes, much harder demand, heat, stress on those 30/40 yr. old coils with a looong dwell electronic ignition... IMO.
If your sure it's a carb problem; it's ignition,
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Offline scottly

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #32 on: September 21, 2010, 08:48:01 PM »
Seafarm, do you have the same symptoms after the switch from the Dyna back to points? The problem may indeed be in the coils. Others have had intermittent heat related coil problems. Intermittent problems are the worst to trouble-shoot in any case!!
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Offline Spanner 1

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #33 on: September 21, 2010, 08:57:09 PM »
Scottly... I can't remember an intermittent coil (even  40 yrs. old ones ) or even a bad one , can you.? And imtermittent coil is not possible... work/no work IMO. Again can't remember a proven bad one, many changed without proof tho' for 'fashion' Dyna  or other ones.... with respect :)
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline scottly

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #34 on: September 21, 2010, 09:04:19 PM »
Hopefully this copy-paste will work..

Well they got it today.

They were just as puzzled as I was because when they tested just the coil all the reading were pretty much fine. However when they stuck it on their test set up, no spark. They dont know why but at least now I know I am not going crazy.

They are sending me a replacement even though it is 4 years old. Cant beat that!
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Offline Retro Rocket

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #35 on: September 21, 2010, 09:13:26 PM »
I have had a bad coils on cars before and they usually work when cold and as they heat up they fail, never had it happen on a bike.

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Offline Spanner 1

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #36 on: September 21, 2010, 09:23:20 PM »
The primary side of a coil is the part that carries the current, the secordary side just ' poof' current ( high tension )... so any failure would be always in the primary side first ( secondary, I would say never )... that said can anyone show some proven open-circuit coils ( primary ) anywhere on this Forum, or did I just miss them ( here every day ) ? Very rare... IMO... First thing to be suspect, last thing to be proven.. IMO.
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline Retro Rocket

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #37 on: September 21, 2010, 09:28:48 PM »
Did you guys ever get the red car type "GT40" coils?, i have had a couple of these fail over the years, they always worked cold and started breaking down when hot. Took me a while to work out what it was because i first suspected condensers.

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If You can't fix it with a hammer, You've got an electrical problem.

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #38 on: September 21, 2010, 09:35:46 PM »
No, but the dang gt-45's, remember them, jeez, if I didn't swap 6 sets of them out before the Autoparts Store told me to 'feck-off'.....
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline Retro Rocket

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #39 on: September 21, 2010, 09:43:41 PM »
No, but the dang gt-45's, remember them, jeez, if I didn't swap 6 sets of them out before the Autoparts Store told me to 'feck-off'.....

I was going from memory mate so it may have been "45"s", they were red. They were sold as an upgrade from stock......never used them again...

Mick
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Offline HondaMan

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #40 on: September 21, 2010, 10:01:46 PM »
The general scenario of coil failures on these Honda coils is: when they go bad, they work like the bike is severely cold-blooded, then they become intermittent and erratic after they get good and hot under the gas tank. Almost all of the ones I've seen fail over the years acted just like this, and it comes from the internal connections getting corroded (just from the years gone by). I have also seen the spark wire (copper) burn in two right where they are spot-welded to the internal end wire from the high-voltage side: this usually makes just one side (like cylinder 1 of the 1-4 coil) miss and foul plugs. A good tug on the spark wire will pull these right out, if it is bad. They cannot be properly repaired: pushing it back in might get you home though.  :D
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Offline Spanner 1

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #41 on: September 21, 2010, 10:06:20 PM »
With respect H.M, your descriptions are all on the H.T. side of the coil... the primary side would not fail and 'come back'   which is what I'm saying.
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline scottly

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #42 on: September 21, 2010, 10:24:06 PM »
the primary side would not fail and 'come back'   which is what I'm saying.
It could, as the windings expand and contract with heat. Intermittent failures are always a #$%* to trouble-shoot, whether mechanical or electrical. We used to use "freeze spray" and heat guns to try to identify heat related failures back in the day... 
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Offline scottly

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #43 on: September 21, 2010, 10:28:23 PM »
Did you guys ever get the red car type "GT40" coils?
Never messed with those, but had experience with Bosch blue coils. Never had any failures with them...
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Offline Spanner 1

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #44 on: September 21, 2010, 10:38:20 PM »
Yeah, the 40 lb. Freeze Spray ( Dang it's heavy!) is the only one I trust to freeze'em back to operation, not sure how long it lasts tho'....Did y'all have that at every gas station in OZ ?.. Retro?.. anyone?
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline Retro Rocket

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #45 on: September 21, 2010, 10:45:21 PM »
Well i haven't been in every fuel stop in OZ {not yet anyway ;D} but i have heard of freezing them but never seen anything like that....

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If You can't fix it with a hammer, You've got an electrical problem.

Offline scottly

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #46 on: September 21, 2010, 10:51:22 PM »
Yeah, the 40 lb. Freeze Spray ( Dang it's heavy!) is the only one I trust to freeze'em back to operation, not sure how long it lasts tho'....Did y'all have that at every gas station in OZ ?.. Retro?.. anyone?

When I used the stuff, it was in an aerosol spray can, like carb cleaner, and that was in an electronics manufacturing plant in Californicate. Totally illegal now, I'm sure. ;)
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« Last Edit: September 21, 2010, 10:53:42 PM by scottly »
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Offline Spanner 1

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #47 on: September 21, 2010, 10:53:52 PM »
Lets all invade HUSH... he deserves it ;D ;) ;D
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline scottly

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #48 on: September 21, 2010, 10:55:02 PM »
Lets all invade HUSH... he deserves it ;D ;) ;D

LOL!!!
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Offline Seafarm

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Re: Feels like a fuel delivery issue but ISN'T!!
« Reply #49 on: September 22, 2010, 12:57:17 PM »
Seafarm, do you have the same symptoms after the switch from the Dyna back to points? The problem may indeed be in the coils. Others have had intermittent heat related coil problems. Intermittent problems are the worst to trouble-shoot in any case!!

No problems with the old points at all.  I'm thinking if new 5 ohm coils replacing the old 3's would lessen the strain on the Dyna S- it may be worth it. Could the heat be generated by the Dyna because it's restricted somehow and  added to the engine temp is too muuuch or vice versa. I need new wires anyway and I think they're all 1 part?
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