1995 Johnson Fast Strike no spark on right side cylinders
Hello everyone.... newbe here to this forum and was hoping someone could provide some assistance. I have a 97 150 Fast Strike that isn't firing on any of the right side cylinders. The engine will start and run but it runs rough and will not stay running. Troubleshooting so far has included disconnecting the shift interrupter switch and temperature sensors but still have no spark on the right side cylinders. Is there any other switches/sensors I should check before spending money on a new power pack? Many thanks in advance for any advice!
Welcome to the forum. Do you have the real OMC service manual for this motor? With no spark on any cylinder on the right side, you need to test the charge coil output in the stator, you have two, one for each side of cylinders. You will need a peak reading volt meter or a DVA adapter for your multi meter.
Thanks 316jughead for your reply. I do not have the service manual or a DVA but looks like I will need to invest. I do have an ordinary digital multimeter. Could I sill use the multimeter to get some kind of reading from the charge coils?
Is the black/yellow shift interrupter wire supposed to be shorted to ground? I unplugged it at the connector, which sits above the rectifier, and tested the male end of connector/wire going into the wiring harness and it's shorted to ground. I unplugged the 6 pin connector (right connector in attached pic) that the black/yellow wire next goes to and the short goes away both downstream and upstream of the 6 pin connector.
I think the black yellow wire should only be shorted to ground if the switch was activated. The easy way is unplug the switch and crank the motor over and see if spark returns. Sometimes the plunger on the switch sticks. There is a ohm meter test for the switch. There is also a blocking diode in the harness that can go bad, but I've never seen that. On the charge coil test only with the DVA can you tell anything.
update.... so i untapped the harness between the 6 pin connector and the shift interrupter wire connector (on top of the rectifier) and found that the black/yellow wire is spliced together to another black/yellow wire that goes to pin G on the left gray power pack connector. So it looks like the wire shorts out within the power pack somewhere? Out of curiosity I cut the black/yellow wire from the power pack (to get rid of the short) and fired up the engine but still no spark on right side cylinders.
You know I want to help, but sometimes it gets frustrating. Why are you going to all of this trouble, when you can just unplug the switch and test for spark?
sorry 316jughead, i didn't see your most recent post. I obviously went above and beyond just unplugging the switch interrupter switch but the short threw me for a loop. The black/yellow wire is shorted to ground regardless of switch position.
I ordered a DVA adapter and a service manual. DVA supposed to arrive on Tuesday after which point I will provide test results. Thank you guys for your help.
The shift interrupter switch has the black/ yellow wire coming out of it which does go to the pack as well as somewhere else in the wiring harness. The other (black) wire that comes out of the interrupter switch goes to ground. So it would seem to me when the switch closes it provides the path to ground via the grounded black wire. It doesn't matter if the switch is open, closed or removed from the circuit the black/ yellow wire is still grounded.
It depends on which side of the shift switch connector is unplugged and tested. The black and yellow wire from the switch would only be grounded if the switch was closed or bad. The black and yellow wire going to the power pack with the shift switch unplugged would still be grounded with the ignition switch in the off position or if the kill switch is pulled. Of course this is with no wiring harness problems.
So here are the test results from performing the OMC service manual steps 6 and 7 which are the charge coil tests and the power pack tests. When doing the charge coil tests (Step 6) I get a very slight voltage output reading of between .01 and .025. When testing the two stator wires I get 200 volts on both the brown yellow and brown white. When performing the power pack tests (Step 7) the readings jump around and get get nowhere near 100 volts coming out of the ignition coil primary leads. But I can get sparks to jump over a half an inch at the plug wires (on the port cylinder bank) so I'm thinking (obviously) my meter is just not accurately reading the output voltage. So do you think the .01 and .025 voltage readings from the charge coil/stator tests are an issue or is this normal. The manual states "Any reading indicates charge coil is grounded. Locate and repair ground, or replace stator assembly". If the previous is not an issue should I purchase a new power pack? Again, I really appreciate you all helping me with this!
Last edited by Dshelton; 09-12-2019 at 06:35 PM.
Reason: grammer eror
Do you have your meter set on DC volts? I think that with the DVA it should be set there. Did you move the meter black lead to the correct wire when testing the output? I'm sure that you must have but I had to ask. Now on the power pack test you must have the PL-88 adapter, or you will not get accurate readings. I don't know for sure about that small voltage, that's almost 0, most of the time if the charge coil is grounded it will show more voltage. You might do the OHM test, but if both coils are putting out 200 volts, that is real good. With that kind of charge coil voltage the high probability is the power pack, I wouldn't think that all 3 coils on that side would go bad at the same time, but strange things happen. If you replace the pack also replace the sensor, with BRP parts.
Last edited by 316jughead; 09-13-2019 at 03:43 AM.
Yes I did have meter set to DC volts and I tested the wires based on the service manual instructions. I switched one of the ignition coil primary leads from a starboard side coil to a port side coil and still got no spark so that eliminated the starboard coils as being the issue. I will order a "BRP" power pack and sensor today and hopefully be back on the water next week. Thanks again for your assistance 316jughead!!
So I replaced the power pack and the motor fired up and ran perfectly, in the driveway sitting on the trailer. Took it to the river and ran it WOT for a couple of 60 second runs. After that it started bogging down when trying to get back on plane but then all of the sudden like a switch was turned on it would just take off and run full speed. It got to the point it just wouldn't even idle anymore, squeezing the primer bulb, choking it at the key switch, pressing on the hot foot, it would start and run for a second or two and then stop. This morning I hooked it up to the garden hose and it ran fine, idled great and would rev up fine. Ran it for 10 minutes or more. Any ideas? I'm stumped.
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