Author Topic: Bike is all back together, but no spark...(SOLVED!)  (Read 2059 times)

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Offline Dave-and-his-550

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Bike is all back together, but no spark...(SOLVED!)
« on: July 30, 2010, 08:22:09 PM »
This is on a '76 550F

Ok, so I've looked over the board and I've done a few tests on the bike. This is what I've done so far:

After adjusting cam chain, I adjusted all the tappets to their proper spacing. I set point gap on 1-4 and 2-3 to .014 in. Points probably need replacing because they are pitted bad. I have yet to clean or sand them down...Is this a must do even if I'm not getting voltage at the blue/yellow wires on the breaker plate? Speaking of which...

I checked for voltage at the breaker plate. First on the yellow wire and then on the blue. Didn't read anything at all. I had negative terminal on multimeter connected to battery ground. Bike was powered on and killswitch set to run.

All fuses are good.

I pulled one capacitor off and tried charging it with a 9v battery for a few seconds, then touched the end of the capacitor to the big part and there was no spark. (Must I use a 12v source for this check?) I'm not sure how to test resistance of it yet. But I'm thinking, maybe the capacitors are bad? Would this cause no voltage at the breaker plate yellow/blue wires? Thus no spark?

I checked my coils. Yellow and black/white wires read 5.3ohms, blue and black/white read 5.2ohms. I checked resistance of plug wire 1 to 4 and it read 15.3 on the 200k ohms scale (So thats 15,300 right?) and 2 to 3 read 15.2.

Not sure what to do now, I'll go back out and pull the other capacitor and check that. Maybe try cleaning the points (Business card damp with brake fluid right?) I need some advice! Can I check for voltage to the coils? The voltage goes from the breaker plate then to the coils right? Should I check the electrical wiring somewhere else?

Also, if someone can tell me how to check resistance of the capacitors. Do I just probe the two ends like in the pic below?



What to do next?  ???
« Last Edit: August 01, 2010, 03:59:09 PM by Dave-and-his-550 »

Offline scottly

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Re: Bike is all back together, but no spark...
« Reply #1 on: July 30, 2010, 08:58:30 PM »
You will only read voltage at the breaker plate if the points are open. If the points are open, and you read no voltage, then check for 12V to the coils, on the black wires.
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Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...
« Reply #2 on: July 30, 2010, 09:07:57 PM »
Ah, there doesn't seem to be any voltage there. I checked it at the little connector from the harness that connects to both black/white wires that go to the coils. Nada.

Offline Spanner 1

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Re: Bike is all back together, but no spark...
« Reply #3 on: July 30, 2010, 09:53:47 PM »
'All fuses are good'.... did you test for voltage on both sides of each fuse with your meter? +probe to each end of fuse and -probe on ground ( battery - is best ). Does your headlight work with ignition 'on' ? and/or.... are the yellow and blue point wires and their capacitor wires connected correctly ( and not grounded) at each point?
« Last Edit: July 30, 2010, 10:01:19 PM by Spanner 1 »
If your sure it's a carb problem; it's ignition,
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Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...
« Reply #4 on: July 30, 2010, 10:44:26 PM »
Give me a moment, I'll go check all the fuses now for proper voltage. They should all read about 12volts?

Also, I have the capacitors out because I was checking them. But when they were in, they were both connected proper.


Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...
« Reply #5 on: July 30, 2010, 10:56:30 PM »
*Update*

Ok I guess they are not all "good"  :D  I'm not getting a voltage reading from the first one or the last one. SP7A Tail, and SP15A. I cleaned the fuse holder and I'm using new 7 1/2 amp fuses (Is that ok?) I couldn't find 7 amp fuses any where locally. (Ok I admit I didn't check the Honda Dealership yet, thats in the town over)

Also, I found a 20 amp fuse in the 7amp main holder, wtf!? I know I did not put that there...

And ya, the headlight works when on.

Offline Spanner 1

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Re: Bike is all back together, but no spark...
« Reply #6 on: July 30, 2010, 11:15:19 PM »
Dave, with the ignition 'off' you should only have voltage ( both sides ) on the 15A( Main ) fuse, ign. 'on' all 3 fuses must show voltage both sides.....
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...
« Reply #7 on: July 30, 2010, 11:33:22 PM »
I do get a voltage reading on the 15A fuse when the ignition is off. Any explanation as to why the first and last one are not getting any voltage with the ignition on?

I'll have to check the manual tomorrow for fuse info, gotta get some sleep for now ...

Offline Spanner 1

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Re: Bike is all back together, but no spark...
« Reply #8 on: July 30, 2010, 11:37:56 PM »
Bad ignition switch...would be the first suspect.
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...
« Reply #9 on: July 31, 2010, 03:40:36 PM »
Ok, so if no voltage at the coil wires, then I should inspect the ignition switch connections?

I'm going to try and clean the connectors and check the fuse harness to see if there are any issues there with melted wiring and such. I guess I'll look through the headlight bucket for any loose wires. There are a few wires I've seen just dangling without knowing where they should go...But I figure they are just non-important loose ends considering the bike powers on, and it turns over. I've looked through the wiring diagram and couldn't seem to place them.

Is there a way I can be certain the capacitors are good?

Offline TwoTired

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Re: Bike is all back together, but no spark...
« Reply #10 on: July 31, 2010, 03:48:19 PM »
The CB550F has a 5 position fuse holder.  The positions at each end are spare fuse holders and not wired.

Power get to the points via the coils.  Power to the coils passes through the main fuse, the key switch, and the STOP RUN STOP switch on the bars.

With Key switch on and the switch in the RUN position power should be on the Black/white wires.

Cheers,
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...
« Reply #11 on: July 31, 2010, 04:25:58 PM »
The circuit is grounded through the spark plugs right? I read that somewhere. I'm getting voltage at the main fuse, but nothing at the coils. Key switch is 'ON' and starter switch is set to 'RUN'

It is a rebuilt kit by the way, that I purchased from a member here. It does have one spare wire that doesn't plug into anything that I could figure. It's a black wire with brown stripe. My original starter switch doesn't have that.

Battery voltage is 11.6 with the ignition switch 'ON' my headlight seems a little dim though.
« Last Edit: July 31, 2010, 04:34:04 PM by Dave-and-his-550 »

Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...
« Reply #12 on: July 31, 2010, 05:01:29 PM »
Hahahah so I found out what my problem was. Apparently it's the 'rebuilt' starter switch that isn't working. I hooked up my old broken one and sure enough the coil wires and the breaker plate wires had voltage readings. Great! After I installed the other one...

My old one has five wires: black, black, black/white, yellow/red, black/red. This new one has five as well: black, black/brown, black/white, yellow/red, black/red.

And I also took apart a little bit of heat shrink on the black wire and found this soldered mess:


So i guess THIS was my real problem, unless there is something else in that starter switch that isn't making a connection... I'm going to go ahead and cut it out, resolder it and see if it'll work. Still dont know what that black/brown wire is for though on the new one  :-\

Should I use 60/40 Rosin Core Solder for PC work? Will it be fine with the copper wiring?
« Last Edit: July 31, 2010, 05:13:20 PM by Dave-and-his-550 »

Offline TwoTired

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Re: Bike is all back together, but no spark...(Found the Culprit!)
« Reply #13 on: July 31, 2010, 05:46:29 PM »
Your solder will work.

Does the "new" switch have a lighting switch on it?
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline Spanner 1

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Re: Bike is all back together, but no spark...(Found the Culprit!)
« Reply #14 on: July 31, 2010, 07:26:56 PM »
Nothing wrong with that soldered connection in your pic. once it was insulated..........with the switch unpressed you must have power on the black wire and the black/red wire ( ign. 'on' of course).... passes power to the headlight fuse ( no power at fuse you report) also must have power to black/white, passes power to the coils.
Your original start/ kill switch has 2 black wires... the new one has 1 black and 1 black/brown.. i.e. black/brown needs to go to black in the headlight shell along with the plain black........... one feeds the start button, the other feeds the kill switch.
« Last Edit: July 31, 2010, 07:49:42 PM by Spanner 1 »
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...(Found the Culprit!)
« Reply #15 on: July 31, 2010, 08:07:14 PM »
The new starter switch has no lighting switch on it for anything.

Spanner, I'm sorry but I'm not quite following ya. The black wire and all the other wires from the starter switch run to connections directly under the coils in that small black box at the harness. They don't run into the headlight bucket. And I do not have a problem with my three fuses, as TwoTired pointed out to me, the other two that I reported as not working were actually just spares being held in place by the unit...Good thing he answered that for me lol

Are you saying that black/brown wire needs to run into the headlight bucket somewhere? One other thing I should mention, I was told the starter switch came off a new model year 550, maybe a 77, 78? So I'm not sure if the black/brown wire applies to my bike  :-\

Offline Spanner 1

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Re: Bike is all back together, but no spark...(Found the Culprit!)
« Reply #16 on: July 31, 2010, 08:33:52 PM »
Didn't know that.... I was sure your righthand wires would go from the start/kill switches either on or in the handlebar and comnnect to their 'mates' in the bucket.... but you say not and go under the tank... is that the stock set-up?
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....

Offline Dave-and-his-550

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Re: Bike is all back together, but no spark...(SOLVED!)
« Reply #17 on: August 01, 2010, 03:58:37 PM »
Yep, its the stock setup. Well I went ahead and repaired the solder joint with some heat shrink tubing. I hooked up the black and black/brown wire to the female mating plug and thankfully everything is powered normal. So it must have been that little soldered joint that was bad.

Thanks for the help Spanner and TwoTired.


Offline Spanner 1

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Re: Bike is all back together, but no spark...(SOLVED!)
« Reply #18 on: August 01, 2010, 06:34:40 PM »
Yeeeeeaaaah  :) ;D
If your sure it's a carb problem; it's ignition,
If your sure it's an ignition problem; it's carbs....