Author Topic: 1974 CB550 No Spark (Read 13239 times)

shade · « **on:** May 26, 2012, 01:06:53 pm »

1974 CB550 with about 20,000 miles

In my last posts I detailed what I've done with this bike so far but here is a quick summary:

The bike was left behind my building in NYC about 8 years ago. It hasn't been started since then. I have no mechanical experience and have been relying heavily on the suggestions from the members of this forum.

I have:
Changed the Oil
Replaced the Spark Plugs
Replaced the Battery.
Bought a new key
Replaced the fuses and cleaned the fuse box.
Cleaned the Points.
De-rusted the Gas Tank through electrolysis, and cleaned the fuel filter in the tank.
Removed the Carburetors and soaked them in Pine Sol.
Adjusted the Floats
Replaced the carb jets.
Also added a little oil to the Cylinders.

I did a spark test in the beginning and it was getting spark, I did a spark test today and it IS NOT.

Any help would be greatly appreciated. Thanks.

LesterPiglet · « **Reply #1 on:** May 26, 2012, 01:13:05 pm »

What spark test did you perform? Is there power to the points? Is there still power in the battery? You will need to start with eliminating the obvious.

shade · « **Reply #2 on:** May 26, 2012, 01:19:03 pm »

I took the spark plugs out one at a time, placed them back into their connectors and placed the bottom against a metal part on the engine, and pressed the ignition. No spark after a few seconds of turning it over. The first time I did this test about a month and a half ago I could see a spark, and on one I held it wrong and actually got a shock.

I have been charging the battery as needed.

I don't know if there is power to the points. How could I check?

Thank you.

LesterPiglet · « **Reply #3 on:** May 26, 2012, 01:26:05 pm »

Remove the contact cover and bridge the contact gap with a screwdriver, with ignition on and kill switch on run. It should spark and also make two of your plugs spark. One set of contacts serves one coil which in turn serves two plugs.

Bodi · « **Reply #4 on:** May 26, 2012, 01:28:17 pm »

"I don't know if there is power to the points. How could I check"
Either get a multimeter or a 12V test light. Remove the tank, the coils each have a black wire and a colored wire. The black wire should have 12V on it with the key and kill switch on. Measure voltage to the frame, the coil holding bolt heads will be a good ground.
If no voltage then you have to find where it is being disconnected. Get a wiring diagram.
If there's voltage, the points may be super dirty or the points wires are cut or disconnected. Least likely is a failed coil especially both at the same time.

shade · « **Reply #5 on:** May 26, 2012, 01:39:58 pm »

Quote from: LesterPiglet on May 26, 2012, 01:26:05 pm

Remove the contact cover and bridge the contact gap with a screwdriver, with ignition on and kill switch on run. It should spark and also make two of your plugs spark. One set of contacts serves one coil which in turn serves two plugs.

Just to be sure I understand do you mean stick a screwdriver into the gap between the points?

LesterPiglet · « **Reply #6 on:** May 26, 2012, 01:49:09 pm »

Quote from: shade on May 26, 2012, 01:39:58 pm

Quote from: LesterPiglet on May 26, 2012, 01:26:05 pm
Remove the contact cover and bridge the contact gap with a screwdriver, with ignition on and kill switch on run. It should spark and also make two of your plugs spark. One set of contacts serves one coil which in turn serves two plugs.

Just to be sure I understand do you mean stick a screwdriver into the gap between the points?

Yes. If the contacts are open bridge the gap with the screwdriver. If they are closed separate them with the driver.

CafeWild34 · « **Reply #7 on:** May 26, 2012, 01:54:18 pm »

When you do that you should see a little spark and if you pull one of the plugs for the points that you are bridging it will also spark. I believe one set of points are for 1 & 4 and the other set is for 2 & 3. I had a problem recently were my points were not adjusted properly and it caused it to get no spark.

shade · « **Reply #8 on:** May 26, 2012, 02:16:24 pm »

I stuck a flathead screwdriver between into the gap between the points and got no spark The key was on and the bike was set to run. Now what?

Thanks.

LesterPiglet · « **Reply #9 on:** May 26, 2012, 02:21:56 pm »

Check your battery and the connections to the points. Do you have a wiring diagram? If not download one from this link.

http://www.sohc4.net/index.php/cb550/books-manuals-guides-2/

Recheck your fuses. The 15amp is the important one in this case.

shade · « **Reply #10 on:** May 26, 2012, 02:38:06 pm »

Battery is good, and connected properly, points seem connected fine, this wiring diagram is out of my league. What could I have done to cause the bike to lose spark? The fuses are all proper. Could it be the timing, that is another part that I just can't seem to figure out.

LesterPiglet · « **Reply #11 on:** May 26, 2012, 02:49:27 pm »

Timing has no effect if you don't have a spark. Make sure you have power to the fuses. Do you have lights?

shade · « **Reply #12 on:** May 26, 2012, 02:50:04 pm »

Yes I have lights.

LesterPiglet · « **Reply #13 on:** May 26, 2012, 02:56:52 pm »

There are yellow and blue wires coming from the points, there are bullet connectors on these wires up behind the carbs. Make sure these are connected. A multimeter would make tracing the problem much easier.

shade · « **Reply #14 on:** May 26, 2012, 03:05:19 pm »

I have a multimeter but I am just going to admit that I really don't how to use it properly. I don't anything about electricity. I really appreciate the help and open to any suggestions.
Of course it started downpouring again outside so it looks like I might be done until tomorrow.
Thanks again.

LesterPiglet · « **Reply #15 on:** May 26, 2012, 03:25:41 pm »

I don't know a lot about electrics or multimeters. I just switch it to continuity and follow the wires.

And here we are having the hottest week in a long time. So hot I can't keep my bike running long enough to sync the carbs.

shade · « **Reply #16 on:** May 27, 2012, 07:58:23 am »

Looks like I will have some dry hours to work on the bike today. Keeping in mind that I am clueless when it comes to wiring and electric, and the list of completed task above, does anyone have any advice for how I should start to figure out why I am not getting any spark?

Thanks

Spanner 1 · « **Reply #17 on:** May 27, 2012, 10:28:17 am »

I'd start over with a fully charged battery. Then I would pull the headlight fuse ( 7A) so as the headlight will not drain the battery while working on the ignition... this will happen fast! if the headlight is on and the bike not running down the road to allow some charging .
Why not use your meter ?.... set the meter to DC volts ( 50 or 100v setting ) and read the voltage at the battery. Then place a piece of card between each point-face and turn the ign 'on'.
With the Black lead still connected to the battery - , touch the Red lead to the 2 point wires, Blue and Yellow at each point. Each must read close to the battery voltage...... Got voltage?.... then 'short' across each point with a screwdriver as suggested by Piglet ( don't remove the card holding the point faces apart ) Need to have a good plug in each plug-cap with the plug threads sitting on the head ( for ground / continuity ).... Any spark now ?

shade · « **Reply #18 on:** May 27, 2012, 12:53:16 pm »

The battery is reading around 11 which I think is correct. I'm trying to read the wires by the points and not getting anything. The meter reads 1 when I connect to the metal where the wires connect to one set of points.

Do I need to replace this entire part?

Thanks for the help.

TwoTired · « **Reply #19 on:** May 27, 2012, 02:08:32 pm »

Name/brand/model of meter?

shade · « **Reply #20 on:** May 27, 2012, 04:14:58 pm »

Sears 982015 Digital Multimeter

Spanner 1 · « **Reply #21 on:** May 27, 2012, 04:28:04 pm »

Did you separate the points with card ? Points closed = no voltage at the point wires .
From TT's chart above you can see 11v is not good

... is the headlight turned off or fuse pulled ?

shade · « **Reply #22 on:** May 27, 2012, 09:29:24 pm »

I put a piece of cardboard between the points, I did remove the headlight fuse (which was very hot to the touch.) I will put a charger on he battery again, it is a brand new battery...

There was also a clicking noise that started the last time I tried to starting it from near where the wires are under the seat.

dragon79 · « **Reply #23 on:** May 28, 2012, 04:26:53 am »

is kill switch on right handle bar switch in correct position? hondas usually turn over with it in the off postion.
adam

LesterPiglet · « **Reply #24 on:** May 28, 2012, 04:42:35 am »

The clicking is likely the starter solenoid. Probably not enough power to activate it or it has a fault. Check it's operation by bridging the two terminals with a screwdriver or something metal. The starter motor should turn over if there is enough power in the battery.

News:

Author Topic: 1974 CB550 No Spark (Read 13239 times)