Topic: Coils. I know it has been answered but I am still lost.

[cbass*gxc]

Ok so today I got my MM out and started testing all the electrical and everything seemed to test out alright except for the spark plug wires for 1 & 4.  The wires for 2 & 3 were getting action but when I stick the leads in 1 & 4 i get nothing.  Do I need to have the points not touching?   So I just checked and one set of points stays touching all the time.  Does that mean they are bad and could that be the reason I am not getting anything?

Thanks
Jay

[mystic_1]

You should have continuity across the spark plug leads regardless of whether the points are open or closed.

Think of it this way:  the primary coil leads (small wires) form a small coil inside the case, which is next to a larger coil that's connected to the spark plug leads.  There's no direct connection between the two sides.  Thus, position of the points wont effect resistance at the spark plug leads.


mystic_1

[TwoTired]

The ignition wires are isolated from the points side in the DC realm which is what your meter lives in.
Check the 1&4 wires with the plug caps removed.

Check each cap individually.

The spark occurs when the points open.  If the points don't open you will get no spark.  The gap should be set between .012 and .016  inch.  The mount plate is then rotated so the points open with the correct crank position.

Cheers,

[cbass*gxc]

Well I took the caps off and tried it and am getting a reading of 9.14 on 1 & 4 and 9.32 on 2 & 3.  The bike was wrecked on the right side (#1) so could that be the reason it isnt working.  Is there a place I can get new caps or does anyone have an extra few they would be willing to part with?

Jay

[TwoTired]

You should get four measurements for the plug caps, not two.  The readings you have given, are good for caps on a CB550. (assuming your are talking about K ohms.)

If your ignition wires get conductivity between the 1-4 and the 2-3 leads respectively, they ought to work.  The points issue has to do with driving the coils.  So, if that is buggared, you can't expect much from the coils.

The right side of the bike, as you sit on it, is where the #4 cylinder is.  Where was the damage?

Cheers,

[cbass*gxc]

Ya the damage was on the right side so I guess #4.  As for the 4 measurements, do you mean the 2 plug wires and the black and blue/yellow?  If so the readings for the little wires are @ .005 Ohms.


I checked the points and when the shaft is rotated so its on the F 1-4 mark the 1-4 points separate but when it is rotated to the F 2-3 the 2-3 points do not separate.  Is there a way to fix that or do I need new points, points plates, stator plates, or all of it?

[Patrick]

Do you know how to adjust the points? There is a little screw that secures the points to the point plate. Loosen it and move the points so that they open when the crank turns. When you get them to open, then adjust them so that they open to the correct gap.

[mystic_1]

Go here and download the 750 manual:

http://forums.sohc4.net/index.php?topic=17788.0

You want section 2, page 43 of the PDF, which is page 91 of the book.

Do points gap first, then point timing.

good luck!

mystic_1

[TwoTired]

Ya the damage was on the right side so I guess #4.  As for the 4 measurements, do you mean the 2 plug wires and the black and blue/yellow?  If so the readings for the little wires are @ .005 Ohms.

No. There are four plug caps to measure independently.  Each coil is measured from bare ignition lead to ignition lead Eg. 2-3 or 1-4, to check continuity of the secondary, without the plug caps.
The black/white and either yellow or blue to check the primary continuity, about 5 ohms if you have stock coils.

I checked the points and when the shaft is rotated so its on the F 1-4 mark the 1-4 points separate but when it is rotated to the F 2-3 the 2-3 points do not separate.  Is there a way to fix that or do I need new points, points plates, stator plates, or all of it?

I descent shop manual will explain how to adjust and set the points and timing.  In fact, the owners manual even does that.  Do you need us to print that information?
You check the gap and the widest or highest place on the point cam.  Then adjust the plate so it opens at the timing mark.    The 2-3 set has its own plate to adjust its timing.  Don't you have any manuals?  Isn't this covered in the FAQ?

Cheers,

[cbass*gxc]

Lloyd I set the points but it still doesnt get any spark at the plugs.  I have tested the coils 2 or 3 times and they all pass the 4 tests you mentioned but I still do not get any spark out of the plugs.  I have tested all the electrical with my MM and everything is as its supposed to be.  The only thing I can think of would be the points but they seem to be working.  I guess it is back out to the garage to check out the points again.

Anyone have any other suggestions?

Anyone have a dyna ignition they arent using?

Also what is the 12v supply you were talking about here?

Quote TT:

If your spark plug boots are removed, arrange the “gozouta” wires so that their ends are about 1/8 inch apart. Each time you apply and disconnect 12v to the “gazinta” wires, there should be a visible arc between the “gozouta” wires.

The 12v source should have a current capability of at least one amp.


Jay

[TwoTired]

The point contacts can get an oxide coating that prevents them from working.  Do not sand, but file a fresh surface on the point contacts.

Are you getting Battery voltage to the coils on the B/W wires?

Stick a match book cover or some insulating material between the points.

Turn on the key switch and measure voltage across the point contacts.  Do you get battery voltage?
 Remove the insulating material from one set of points.  When the points close, the battery voltage across the contacts s/b very near zero.
Check each set of points in the same manner.

Are other electrical things on the bike working?  Have you examined the negative terminal connections between battery, motor, and frame?

What spark plugs are you using?

Also what is the 12v supply you were talking about here?

A 12V supply can be anything that provides that potential with the required current.  A fully charged 12 V battery would work.

You need to make a connection to both the B/W wire and either the yellow or blue coils wires.  This means connection to the POS (+)  and NEG (-) terminals of a charged battery.  Each time you remove one of these connections, the spark leads should produce an arc if the wires are close enough together.

Cheers,

[cbass*gxc]

The point contacts can get an oxide coating that prevents them from working.  Do not sand, but file a fresh surface on the point contacts.

Are you getting Battery voltage to the coils on the B/W wires?

Stick a match book cover or some insulating material between the points.

Turn on the key switch and measure voltage across the point contacts.  Do you get battery voltage?
 Remove the insulating material from one set of points.  When the points close, the battery voltage across the contacts s/b very near zero.
Check each set of points in the same manner.

Ya i tested them both that way and they are getting voltage.  About .009 + or -.  Dont remember what I had the volts set to but when I tested them closed there was not much.

Are other electrical things on the bike working?  Have you examined the negative terminal connections between battery, motor, and frame?

Ya I went over it again and everything is working properly that I can tell.  All the turn signals, dummy lights, running/parking lights, gauge lights, and all the relays and other electronics on the bike.  Every time I test the 1&4 plug wires with the plug caps on I get nothing but with them off i get a reading.  On 2&3 i get a reading no matter if they are on or off.  My mechanic friend came this afternoon and we tried to get a spark on any of the plugs and couldn't.

What spark plugs are you using?

I am using NGK 7912 D7EA.  The guy that I bought this bike from had purchased these before I bought the bike.

A 12V supply can be anything that provides that potential with the required current.  A fully charged 12 V battery would work.

You need to make a connection to both the B/W wire and either the yellow or blue coils wires.  This means connection to the POS (+)  and NEG (-) terminals of a charged battery.  Each time you remove one of these connections, the spark leads should produce an arc if the wires are close enough together.

I will try this tomorrow when I get home from work.  We tried putting the wires close together today and crank the motor with the kick start and didnt get anything. 

Also my started switch on the handle bars does not make the starter turn when pushed but i checked the starter inside and out today and was getting a continuation. 

[TwoTired]

Ya i tested them both that way and they are getting voltage.  About .009 + or -.  Dont remember what I had the volts set to but when I tested them closed there was not much.

This does not sound right.  You should be getting near Battery voltage (12V) across the point contacts when they are open and Zero V when they are closed.

Cheers,

[cbass*gxc]

http://cgi.ebay.com/ebaymotors/Dyna-S-Hi-Performance-Ignition-Honda-CB500-550-750-Four_W0QQcmdZViewItemQQ_trksidZp1638Q2em118Q2el1247QQcategoryZ34284QQihZ015QQitemZ250178493287QQrdZ1QQsspagenameZWD1V

So would this be the ignition I would need to get to replace my original points?  I think I am just going to get one of these and be done with it.  Or since I am having problems with the coils as well should I just get this whole package?

http://cgi.ebay.com/ebaymotors/honda-cb750-chopper-dyna-ignition-package-w-acel-wires_W0QQcmdZViewItemQQcategoryZ35594QQihZ012QQitemZ220211242795QQrdZ1QQsspagenameZWDVW

Are the ignitions for the 750 and 550 the same? 

Can I run just the ignition with factory coils and be alright?

[andy750]

The Dyna S will work with stock coils...but if you have bad coils (have you verified this?) then replacing the points wont help much. Personally I think the kit for $290!! is overkill here...but hey its your $$s.

Have you checked the wiring coming from the points to the coils? Black/white wire, yellow, blue? Are you getting the starter to turn over when you push the starter button? Condensors could be bad?

For the 550 (and Llyod will correct me if Im wrong) -

"I am using NGK 7912 D7EA.  The guy that I bought this bike from had purchased these before I bought the bike."

Are stock plugs to sue for the CB550.

Good luck
Andy

[HondaMan]

Can you post a closeup pix of the points plate, especially the offending 1-4 points?

[cbass*gxc]

Well I used my MM and checked for continuance through the wires on the coils and I am getting a good reading there but I have not actually tested the wires between the points and coils.  I will add that to my list for this afternoon.  Like I said I tested for continuance on the plug wires and with the caps on i get a reading from 2&3 but none from 1&4 but with the caps off I do get a reading on 1&4.

As for the starter I cant get the button to do anything but I tested the starter motor and the starter magnet like it says to in the manual and am getting the readings it says you should get with these.


Ya I will get some good pics this afternoon.

Man this #$%* is frustrating!

Ok I was looking over the electrical in the manual and I have not done the ignition coil performance test yet but do not have access to a tester.  Where would be the best place to pick one of these up?

All the other electrical on the bike works as it is supposed to.

[cbass*gxc]

 Condensors could be bad?

Ok so I just searched the repair manual and cant figure out what the condensers are.

[cbass*gxc]

I just talked to the guy that I bought my bike from and he said he has an extra set of coils that I can borrow and see if that is the problem.  So when I get home I will see what i can come up with.

[mystic_1]

Ok so I just searched the repair manual and cant figure out what the condensers are.

The condensers are the little metal canisters that sit on your points plate.  They are essentially capacitors that are there to absorb the electrical backlash that happens as your points open, thus preventing arcing at the points.

mystic_1

[cbass*gxc]

Sweet I will check those as well.  I thought thats what they were but wasnt for sure.  I printed out the electrical part of the repair manual and am taking the rest of the day off work and going to go home and start on the first page work my way through marking off as I go.

[cbass*gxc]

Alright here are the pics of the points.  The crank is turned so they are on the F mark.  I see that they are not quite right so I am going to adjust them a bit.

1&4


2&3

[tomswift]

you may be frustrated, but the light ahead is not a train in the tunnel my friend...

there are many reasons why you can get no spark on one side... but let's start at the simple things

1. if I see no spark, I pull the caps and check for continuity...you did this...check... the reading was 9.something, this is good if you meant 9.x K-ohm...or about 9xxx ohm

2. Plug caps die by getting a higher resistance internally... checking each one will determine if only one has died, or if both are ready for the square file... they should be somewhere between 3K and 5K ohm

3. if you have continuity and okay caps, put them together, plug in a sparkplug, lay it on an unpainted surface that is grounded (or use a jumper cable) and manually open/close the points(with key on of course). If this doesn't cause a spark, now you have something unusual happening

4. Check voltage at the supply to the coils... this should read 11.x - 12.x with key on, depending upon your battery. It is very possible that the bullet connectors are corroded, wires broken, or gremlins live in your harness, but we can exorcise all these demons!

5. Eliminate the coil by connecting a wire directly to the battery, then to the disconnected power supply wire on the coil... then a ground from the yellow/green directly to the neg on the batt. Put the positive on the black wire, pull it off, then touch it, then pull it off...you should see those sparkies flashing a nice fat spark. If they do, then go to next step...if they don't then replace the coil

6. Check continuity from ground wire(yellow/green) at coil to points...with wire disconnected at points... all good, keep going....no continuity, find that demon in the wiring

7. reconnect points, read voltage near the coils as the points are opened and closed manually ... it should jump to system voltage when the points open, if not then suspect the condensor (rarely fails, but it happens)

To summarize:
-check plug caps
-check coil internally
-check supply voltage to coil
-check coil operation with jumpers
-check continuity back to points
-check condensor

These old points ignition systems are not bulletproof, but not too hard to diagnose if you have done it 30-40 times LOL. Good luck!
TS99

PS...quick check on condensor... ground the body, touch pos. wire to the pos on the batt... monitor voltage when disconnected...should take about 4-5 sec to get under 0.5V...if it drops too quick you have a short

[mystic_1]

Another quick check for the spark plug caps is to switch them side-for side and see if the problem follows the caps.

mystic_1

[andy750]

Another quick check for the spark plug caps is to switch them side-for side and see if the problem follows the caps.

mystic_1

+1

...Im not sure if you have done this or not...but forget the MM and try and see if you get spark at all at the plug -undo each plug in turn and put it cap back on....touch against engine, press starter button and see if you get spark or not. Do this for each plug. MAY tell you if plug is bad, leads are bad or coils are crap....but easy to do.

good luck
Andy