1986 9.9. Charge coil defective? (update)

[steviecops]

Hi<br />I have a 1986 Johnson 9.9 that I bought as a non runner. Compression is good, but it has no spark. The previous owner had a new powerpack fitted a couple of months ago and the engine has run since it was fitted.<br /><br />I'm just trying to get my head around outboard electrics, so I'm not sure if I'm on the right track with my trouble shooting. I bought a DVA multimeter and heres what I've tested so far.<br /><br />HT leads were both shot, so I've replaced with new. Stop button test checked out O.K. One ignition coil was showing high ohms on the primary side, but I took it off and cleaned the ground tab and now it checks out O.K. Sensor coil checks out O.K. Charge coil is showing very low ohms and low voltage at cranking speed. Took flywheel off, but the charge coil looks good, ie, no burn marks, cracks or goo. Haven't checked the powerpack yet, as I need to replace the coil first.<br /><br />Does this sound as if I'm on the right track or not?<br /><br />Thanks in advance.<br />Steve

 

[R.Johnson]

Re: 1986 9.9. Charge coil defective? (update)

Your DVA will only do static tests, " ohms", for running tests you need a peak-reading volt meter. You should have about 250 - 300 volts to the pack, the same coming out to the coil.

 

[steviecops]

Re: 1986 9.9. Charge coil defective? (update)

My DVA is a peak reading meter, or at least I think it is! It's the quicksilver one and I ordered it through my local outboard parts dealer.<br /><br />I can't remember the exact reading off the top of my head, but the voltage from the charge coil was about 20-25 volts I think. Also, the ohms reading was way down from what it should have been. Instead of 550-650 ohms, it read about 230 ohms. I tested to see if it was grounding out and it wasn't.<br /><br />I'm thinking that the charge coil is at fault, but as I said before, outboard electrics is voodoo to me right now! Is it unusual for the charge coil to go completely bad resulting in no spark at either plug?<br /><br />Thanks<br />Steve

 

[rodbolt]

Re: 1986 9.9. Charge coil defective? (update)

hello<br /> rerun the test with the pack disconnected. much below about 70 volts and the coil primary will not spark.is the motor a pull start or electic and is your meter an analog or digital?<br /> good luck and keep posting

 

[steviecops]

Re: 1986 9.9. Charge coil defective? (update)

Hi Rodbolt.<br />I did the voltage test on the charge coil with the pack un-plugged and jumper wires connected to the A and D terminals of the armature plate side of the plug.<br /><br />The motor is a pull start and my meter is an analog one.<br /><br />One thing confusing me is something written on the instruction booklet for my meter. It says that OMC motors produce a negative spike and to reverse the leads as shown in the OMC manuals. I did try reversing the leads, but the voltage reading came out the same both ways.<br /><br />Thanks<br />Steve

 

[rodbolt]

Re: 1986 9.9. Charge coil defective? (update)

if you test the charge coil with the pack unplugged its an alernating current. its when you test the pack output that it becomes polarity sensitive. there is no good way to test the flywheel magnents but weak magnents will cause that problem as well. however with the resistance being about half of spec and the voltage output so low I would say the charge coil is bad. I hate to ask but are you sure your reading the correct scale on the meter face? that is a draw back to analog and has bit me once or twice over the years. <br /> that meter has a range on the lower right quadrant marked DVA. are you sure that is where the selector is set ?<br />what is the scale ranges for the DVA settings?<br /> good luck and keep posting<br />ps also what is the trigger voltage ?

 

[steviecops]

Re: 1986 9.9. Charge coil defective? (update)

Rodbolt.<br />Now you've got me thinking! I'm pretty sure that I read the meter on the right scale, and the meter was definately set on the DVA quadrant. The meter gives scales of 2, 20, 40, 200 and 400 on the DVA quadrant. There are two voltage scales on the centre section of the guage dial, the upper one goes from 0 to 40 and the lower one goes from 0 to 20. That's a bit confusing. The booklet says that DC and AC voltage are both to be read on the upper scale, but doesn't tell me which scale to read DVA voltage on.<br /><br />Having read the booklet again, it says that on the 400 V scale, I have to multiply the reading X 10. So the 20-25 volt reading I got was actually 200-250 V. I'll have to double check that because I'm sure that it was way down on what it should have been.<br /><br />The trigger tests as per the manual. 40 ohms on the resistance test. No voltage when tested to ground. Can't remember exact voltage with test leads connected to terminals B and C, but it was over the 2 volts required in the manual. <br /><br />If the charge coil voltage is O.K, is the low ohms reading significant?<br /><br />Thanks<br />Steve

 

[steviecops]

Re: 1986 9.9. Charge coil defective? (update)

I've read about it a thousand times on here that the powerpack earth connection should be one of the first things to check when you have no spark. I'd assumed that as the pack was replaced a few months ago by a shop, that the earth would be good. Wrong! So I cleaned the area thoroughly and now had a spark on both plugs. However, the engine still wouldn't start, so I re-did all my checks and here's what they came out at.<br /><br />Charge coil 300 ohms instead of the 550-600 stated in the manual. Voltage output from charge coil came out at 70 volts instead of the 230 minimum stated in the manual. Everything else checked out O.K, so it looks like the charge coil is causing the problem. Just to be sure I was doing the tests right, I tested known good Johnson 9.9 and got a voltage reading of 250.<br /><br />My new charge coil is on order, hopefuly it'll do the trick.<br /><br />Thanks<br />Steve