DO THE TON

Blood Sweat Tears and Grease => Electrical => Topic started by: tahitianrider on Jul 13, 2018, 17:21:55

Title: CB360 spark problems
Post by: tahitianrider on Jul 13, 2018, 17:21:55
Hi!
I have picked up a while ago a CB 360 that was running but with many problems: sometimes running on 1 cylinder at idle, severy misfiring when riding, stalling when hot and couldn't restart etc.

I suspected of both fuel and ignition problems, so I did a lot of work on it :
- Ultrasonic cleaned the carbs and rebuilt them with new parts (jets, o-rings, mixture screws, etc.)
- Tank was rusted with a mix of rust and epoxy (bad previous epoxy job) so I'm cleaning it right now, but testing the bike on my workshop fuel bottle anyway.

On the electrical system :
- I suspected a bad ignition timing, and when checking it with a test lamp it was indeed bad. So I installed new contact breakers and set the ignition timing correctly (it is hard to get it perfect but I'm very close : it fires at less than 1mm from the fire timing marks)

I tried to start the bike (from a workshop fuel bottle so the carb do get fuel correctly) but it wouldn't start at all (although I was starting before I tried to fix everything)
When check the sparks (with a brand new plug of course) I have no spark at all on the right cyl, and a weak blue spark on the left cyl.
The ignition coils are really warm so they get power. But they look like the original ones, they look very old and not in a perfect shape lol.

I would like to know if I can check other things before trying to order new parts (coils, condensator...) ? or do do the problem comes from the coils ? should I try to replace them first ?

Thanks a lot for the help and sorry if a similar problem has been posted already, I did search the forum, I already learned a lot on ignition timing that way :)
Title: Re: CB360 spark problems
Post by: advCo on Jul 13, 2018, 18:15:27
Coils could be suspect. First make sure you have power TO the coils with a test light. From there, you can test the primary and secondary resistances on the coils to determine whether they are within spec or not using a multimeter.
Title: Re: CB360 spark problems
Post by: irk miller on Jul 13, 2018, 19:16:05
Primary should be 3 ohms and secondary around 14 ohms.  If you have resistor caps and testing shows infinity on secondary resistance, take the plug caps off and test without to rule out the caps.  You can test the caps off the wire.
Title: Re: CB360 spark problems
Post by: raptormeat on Jul 13, 2018, 23:13:04
I never knew this one until yesterday, but it explains weak spark,  Check the resistance between the condenser bracket (gold) and ground, the condenser may have a weak ground. I'll be honest the best thing to do is buy a refab  wiring harness, new coils, and an e ignition, about 400 total. Also make sure the points wire is not grounding on cover, take cover off and test.
Title: Re: CB360 spark problems
Post by: irk miller on Jul 14, 2018, 01:23:06
I paint the inside of my points cover with liquid tape.  That takes care of the potential for ground on the cover.
Title: Re: CB360 spark problems
Post by: tahitianrider on Jul 14, 2018, 06:15:25
Thanks for you replies!! :)

So I tried tout measure my coils but I'm not really sure how to do it? I tried to put the multimeter on both each side of the coils where thé cables connect. I get nothing on the right coil and "0.00" on the left coil. But the right cool has some kind of hard plastic goo on its terminals, looks like a 20 y/o fix.
I think I'll be better off ordering new coils right away, wouldn't I ?
Title: Re: CB360 spark problems
Post by: irk miller on Jul 14, 2018, 09:09:27
To test primary, you put each lead from the meter on each terminal for the coil.  You can plug them into the ends of the coil leads.  To test the secondary, you take one meter lead and plug it into the spark plug cap and leave the other meter lead plugged into a coil wire. A good coil is a good coil.   I've actually repaired those old coils to run them by pulling the spark plug wire out, trimming the end to get a clean wire, then plugging and epoxying it back in.
Title: Re: CB360 spark problems
Post by: Sderbyshire on Jul 14, 2018, 10:05:18
The coils on my cb360 look that bad and work fine!

A methodical testing approach is needed, the system is simple.

Primary circuit get power from ignition and earth when points are closed
Secondary earths via the spark plugs as the induced voltage when the points open os ‘large’

So if you have a working primary circuit, ie power and points, then as long as the coils are functional, check their resistance, it ‘has to work’ :-)

Steve


Title: Re: CB360 spark problems
Post by: tahitianrider on Jul 14, 2018, 10:17:19
So I checked the coils corectly this Time, this is what I get :
Right coil : primary 00 ohms, secondary 17 ohms
Left coil : primary 00 ohms, secondary 19 ohms.

Not sure what this means ? Especialyy the "000" Reading ?
I tested primary but connecting the meter leads tout each wire coming out of the coil and secondary from plug boot to ground wire out of the coil.
Title: Re: CB360 spark problems
Post by: irk miller on Jul 14, 2018, 10:49:46
You have a break in your primary.  It could be that the wires need re-soldered or they're really corroded.  Just to be sure, you could make sure the leads are good and clean.  Since you got a good reading on the secondary with ground, you can test with the other wire to see if you still get nothing.  Also, test your meter by touching the two leads together.  Usually, you get about .5 ohms or so,  but just make sure it's not a crazy number like 3 ohms.

I've had to repair stock coils by replacing leads on the primary side.  Sometimes, they get bent back and forth, and pulled enough that they get disconnected where the leads go into the coil body.  You have to remove the old epoxy, clean the contact point, and solder a lead back on.
Title: Re: CB360 spark problems
Post by: tahitianrider on Jul 14, 2018, 11:13:14
I tested the secondary again with the other wire that goes to the contact breakers. I get a solid 19.5 on the left and 17.2 on the right , so about the same.
When connecting my 2 meter leads together I get 000.

The leads on the coils are far from clean Indeed but since I have the same secondary Reading with the other wire doesn't that mean that it may not be thé problem ?
Title: Re: CB360 spark problems
Post by: irk miller on Jul 14, 2018, 11:30:45
What setting do you have the meter when testing primary?  It should be on 200.
Title: Re: CB360 spark problems
Post by: tahitianrider on Jul 14, 2018, 11:43:33
Yes I have it on 200, so does that means that there is a problem with the coils themself and not the leads ?
Title: Re: CB360 spark problems
Post by: tahitianrider on Jul 31, 2018, 15:22:22
So I found a great deal on some coils and installed brand new coils along with new plug wires and cap.

Yet the bike didn't fire up. So I check the right cyl plug: no spark at all, then I wanted to check the left cyl and suddenly no more power at all: the main fuse blew up...
So I'm pretty sure there is a short somewhere... The wires at the points cover seems fine.

The I checked the wiring harness, which was a total mess... The previous owner made this bike a cafe racer and did a terrible job pretty much everywhere. 75% of my work on this bike is about fixing the mistakes he made...

So in the harness, first there are a ton of unplugged female terminals, well I guess that is because he removed all the speedometer and techometer units...
They were somehow insulated though.
BUT I found an unplugged white/red (or green/ red? Im color blind...)wire that was not insulated at all and touching the frame. Givien its color I'm pretty sure it has power and may have cause the short.
I now need to find what this wire is and where to plug it.

Oh and many terminals were loose too which may explain why I had no spark ? But the coils did feel hot when I tried to start previously...
Title: Re: CB360 spark problems
Post by: tahitianrider on Jul 31, 2018, 15:23:11
The wire
Title: Re: CB360 spark problems
Post by: Maritime on Jul 31, 2018, 16:43:55
that is green w red stripe. look it up on the wiring diagram and see what it does.
Title: Re: CB360 spark problems
Post by: tahitianrider on Jul 31, 2018, 17:52:56
So on the wiring diagram there are :
- One green and red wire: this one goes to the starter magnetic switch and the clutch switch.
- One light green and red wire: this one is for the neutral indicator light.

I'm thinking this is the light green and red wire for the neutral light isn't it? Since the previous guys removed all the indicator light and did a terrible job, I would not be surprised if he just let that wire like that after removing the neutral light without even insulating it...
So it may have cause the short and blew up the fuse, but may not be the cause for no spark at all.

Maybe my kill switch is faulty?
Unfortunately I have to wait to receive my new fuses to figure this out
Title: Re: CB360 spark problems
Post by: raptormeat on Jul 31, 2018, 19:11:10
that might be your problem. again, check that condensor mount to ground resistance...the one with all the dust on it...

also, this is worth it, no more fuses.
https://revivalcycles.com/products/waterproof-3-circuit-breaker-block
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 01, 2018, 06:25:55
Yes I'll check that, I also have a brand new condensor I didn't installed yet, I will install the new one and check that ground. What should be the resistance from mount to ground?

That circuit breaker looks nice indeed
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 02, 2018, 15:57:01
So I installed the new condenser and insulated the wires terminal that were not with electrical tape.

I didn't had 15A main fuse so I used a 10A fuse from a CX500 Sport I had laying around,

I turned the ignition key on, it had power for about 30sec, didn't had the time to test for spark before the main fuse blew up again...

I find this weird... it didn't blew main fuses up before... then I changed the coils and it starts blewing up fuses... I mean, if there is a short somewhere on the wiring harness, why did it not happened before?

Oh and do you guys know if the CB uses fast fusion 15A fuses or slow fusion 15A fuses?

Thanks again for all the help
Title: Re: CB360 spark problems
Post by: Maritime on Aug 02, 2018, 15:59:05
If there is a wire with a short, all you had to do was wiggle it the right way installing the coils and make it blow fuses.  check all the wires you wuld have touched or moved while putting the coils in, one must have a crack or something and is now touching the frame or another wire.
Title: Re: CB360 spark problems
Post by: Sonreir on Aug 03, 2018, 14:28:49
What coils are you using?

Stock coils (five Ohm) and headlight alone will pull 8A. Pretty easy to pull an extra two and blow a 10A fuse.
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 03, 2018, 16:40:04
If there is a wire with a short, all you had to do was wiggle it the right way installing the coils and make it blow fuses.  check all the wires you wuld have touched or moved while putting the coils in, one must have a crack or something and is now touching the frame or another wire.

Yeah you're right I'm gonna check that again.

Quote
What coils are you using?

Stock coils (five Ohm) and headlight alone will pull 8A. Pretty easy to pull an extra two and blow a 10A fuse.

I'm using high voltage coils I found on ebay, not sure of their reference, here is a picture.

Yeah the 10A was just a temporary fix because I did not received my 15A fuses yet
Title: Re: CB360 spark problems
Post by: crazypj on Aug 03, 2018, 23:06:13
Check you have the insulating washers in correct place on points bolt. You probably have a green wire plugged into a red/green somewhere or another earth/ground lead in wrong place. It sounds like it's going through some sort of load or fuse would blow instantly. 10 amp will work as long as you don't have any lights on. If you have an old indicator/bulb holder (21w~23w bulb) connect it across fuse contacts. (leaver fuse out, alligator/crocodile clips on leads) If you have a short, the bulb will light up. Leave it there while you check various connections.It saves on blowing a ton of fuses while troubleshooting. The light green/red neutral wire is a grounding wire, it normally will have battery voltage after neutral light bulb (bulb is load so fuse doesn't blow) If you have bulb holders in speedo and tach, neutral will have black in and red/green out
Title: Re: CB360 spark problems
Post by: Sonreir on Aug 06, 2018, 13:14:47
Do you have a multimeter? If so, can you measure resistance between the black and the green wire for the coil?
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 06, 2018, 13:41:22
I just received my 15A fuses but did not had the time to work on the bike today,

Quote
Do you have a multimeter? If so, can you measure resistance between the black and the green wire for the coil?

I just checked the resistance between the black and green wires and I have 0.00 ohms on both coils... (multitmeter set to 20k), shouldn't that be 3 ohms?? Did I just get ripped off buying brand new broken coils?

Quote
Check you have the insulating washers in correct place on points bolt. You probably have a green wire plugged into a red/green somewhere or another earth/ground lead in wrong place. It sounds like it's going through some sort of load or fuse would blow instantly. 10 amp will work as long as you don't have any lights on. If you have an old indicator/bulb holder (21w~23w bulb) connect it across fuse contacts. (leaver fuse out, alligator/crocodile clips on leads) If you have a short, the bulb will light up. Leave it there while you check various connections.It saves on blowing a ton of fuses while troubleshooting. The light green/red neutral wire is a grounding wire, it normally will have battery voltage after neutral light bulb (bulb is load so fuse doesn't blow) If you have bulb holders in speedo and tach, neutral will have black in and red/green out

I will check the points bolts again but I just changed the contact breakers and paid attention re installed them correctly,
The 21w bulb instead of the fuse is a great idea! I don't think I have that in my garage unfortunetaly :(
Title: Re: CB360 spark problems
Post by: Sonreir on Aug 06, 2018, 13:42:38
I just received my 15A fuses but did not had the time to work on the bike today,

I just checked the resistance between the black and green wires and I have 0.00 ohms on both coils... (multitmeter set to 20k), shouldn't that be 3 ohms?? Did I just get ripped off buying brand new broken coils?

Three Ohms should be the absolute minimum. Five Ohms would be better, in my opinion.

Set the meter to 200 and try again?
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 06, 2018, 13:52:17
Three Ohms should be the absolute minimum. Five Ohms would be better, in my opinion.

Set the meter to 200 and try again?

Still 0 Ohms with the multimeter set to 200, damn! Hopefully I'll be able to get my money back through ebay/paypal.

I did check the secondary resistance too (green wire to plug cap) and I have a correct 14.6 ohms
Title: Re: CB360 spark problems
Post by: crazypj on Aug 06, 2018, 14:00:34
Pretty much any bulb holder and bulb wirth some wires will work, old tail light, automotive.With the bikes you have listed I would think you have an old indicator or something?
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 06, 2018, 14:07:52
Pretty much any bulb holder and bulb wirth some wires will work, old tail light, automotive.With the bikes you have listed I would think you have an old indicator or something?

Oh okay, yes I totally have that! I have many indicators and tail light units, I didn't think an old school type indicator bulb was 21w ! I though I needed a headlight assembly for that much watts.
I will make something out of an indicator when I'll search for that short in the wiring, thanks for the trick :)
Title: Re: CB360 spark problems
Post by: crazypj on Aug 06, 2018, 14:21:13
Depending where you are in the world, indicator bulbs vary between 18w and 23w. Headlight bulb will work as well but if you have a dead short it gets a bit bright and a bit hot. Headlights are usually 35~65w plus, it has a higher amp draw so battery voltage will drop faster (over 5amps for 65w, 12v bulb)
Title: Re: CB360 spark problems
Post by: Sonreir on Aug 06, 2018, 14:31:15
Still 0 Ohms with the multimeter set to 200, damn! Hopefully I'll be able to get my money back through ebay/paypal.

I did check the secondary resistance too (green wire to plug cap) and I have a correct 14.6 ohms

Looks like you have CDI ignition coils. You'll definitely want to get those replaced.
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 06, 2018, 15:46:54
Looks like you have CDI ignition coils. You'll definitely want to get those replaced.

Hum, the seller I bought the coils from advertised them as perfectly compatible with the 1976 CB360... as a direct swap from the OEM ones, I will need to get my money back...

Theses should fit without problems right ? Plus I already bough from 4into1 and I know they are reliable, although I need to pay 30% of custom taxes to france.

https://4into1.com/ignition-coils-and-caps-honda-cb-cl-sl350k-cb-cl-cj360/

Quote
Depending where you are in the world, indicator bulbs vary between 18w and 23w. Headlight bulb will work as well but if you have a dead short it gets a bit bright and a bit hot. Headlights are usually 35~65w plus, it has a higher amp draw so battery voltage will drop faster (over 5amps for 65w, 12v bulb)

That is good to know thanks, there is no chance of frying the bulb of the indicator doing so?
Title: Re: CB360 spark problems
Post by: crazypj on Aug 06, 2018, 19:29:57
Only if you drop it  ;D High load or dead short will just make it light up as normal, it should dim if everything is OK as whatever load you have on circuit will 'share' the voltage
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 08, 2018, 11:29:30
Haha okay, nice trick anyway :)

I just sent back my faulty coils, waiting to receive my new set of 5 ohms coils from 4into1 to test everything again.
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 21, 2018, 07:08:35
So I just came back from a week of hollidays (I spent working on my CX500 at my parents place :) )and received my brand new coils, these one are finally fine: a good 5 ohms primary and also my new 15A fuses.

I installed everything on the bike, first of all, I do not blow fuses anymore, even with the headlights on! so this is good.

However, I still have no spark at all on the right cylinder, I do have a blue spark on the left cylinder.

When I did the ignition timing, I only replaced the left contact breaker (because the brand new right one I received was faulty with wrong holes for bolts...), could this be the problem? or maybe the contact gap is incorrect?

Here is a quick slow motion video of the contact breakers when trying to start the bike, I can see sparks on both side:
 
https://www.youtube.com/watch?v=SGoIupHeDSY
Title: Re: CB360 spark problems
Post by: irk miller on Aug 21, 2018, 10:08:57
Do you have capacitors on there?  Doesn't look like by those sparks.  Do you have resistor caps and do they both check out?  If you're getting spark at the points, power to both coils, but no spark at the plug, then the problem is your plug wire- either where it connects to the coil or the cap.  Also a chance you have a fouled plug, so check that too.
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 21, 2018, 11:06:54
I finally figured it out!! well to be honnest the potential problem has been mentionned before here, but when I check it the first I've somehow not seen it.

I tried to start without the points cover and boom, perfect sparks!
So I cheked the wires again and they were not shortening to the cover... but then I check the connector of the wire to the contact breaker of the right cylinder, and it is the connector that was touching the cover so making a short and so no spark on the right cylinder!
So I pushed the connector further back inside, put back the cover and the bike fired up perfectly at first try!! :)

I feel so stupid for not seeing this the first time, plus you guys mentionned the problems with wires touching the points cover.

The bike idle smoothly and is no longer running on one cylinder at idle :) I'm going for a test ride right now !
Title: Re: CB360 spark problems
Post by: irk miller on Aug 21, 2018, 11:10:48
I paint the inside of my points covers with liquid tape.  Just a little extra insurance against shorting.
Title: Re: CB360 spark problems
Post by: tahitianrider on Aug 21, 2018, 11:38:14
That's a great idea! I had the exact same one I thought "hum I should liquid tape the inside of the points cover", I was worried the performix liquid tape would not hold the heat but if you don't have any problems I'll do it too :)

I just came back from the test drive: the bike runs perfectly!!
Before it was bogging as hell, I couldn't rev the bike properly and it was running on one cylinder at idle, plus it was stalling when not and would not restart...

Now that I did the ignition timing, new coils, condenser & plugs, plus I fully rebuild the carbs and gas tank, the bike is perfect I love it :)

Thanks a lot for your help on this problem!!
Title: Re: CB360 spark problems
Post by: crazypj on Aug 21, 2018, 13:29:15
It's a good idea to put a drop of engine oil on the felt and a tiny bit of grease on the 'ledge' where points hell contacts the points cam. It reduces wear on the rubbing block so timing stays set longer although new points will always 'bed in' and need re-setting at 300~500 miles