No Spark 1993 90hp Force (Sportjet)

[cowansauto]

I have a 1993 Sportjet 90hp engine in my Sea Rayder. It has no spark at any coil. The engine will turn over but i have no spark on any of the three plugs using an inline spark tester . I have attempted to use the following links to try to diagnose the problems. It does have the red stator kit installed.

Here the results from the CDI test mentioned in this link:
http://www.cdielectronics.com/InstallSheet/IS-134-7029-3.pdf

NO SPARK ON ANY CYLINDER:
1. Disconnect the black/yellow stop wire AT THE PACK (switchbox) and retest. If the engine’s ignition now has spark, the stop circuit has a fault-check the key switch, harness and shift switch.
Results:NO SPARK on #1 plug

2. Disconnect the yellow wires from the stator to the rectifier and retest. If the engine has spark, replace the rectifier.

Results: NO SPARK on #1 plug

3. Check the cranking RPM. A cranking speed less than 250-RPM will not allow the system to fire properly.

Haven't been able to check this just yet. Having issues with timing/tach light

4. Check the stator resistance

Results:680 ohms from the Green/White wire to the White/Green wire
"OL" reading on meter from the blue wire to engine ground

Also wanted to post:
-Trigger Resistance: ohms read close to spec at 1200ohms

 

[pnwboat]

Re: No Spark 1993 90hp Force (Sportjet)

Make sure the magnets under the inner circumference of the flywheel are intact and not broken or missing. Should be six of them.

Does your ignition system have a switch box? If so, you need to test the out put of the switchbox to the ignition coils. You need a DVA meter to test properly. You should see approx 200 to 360 volts at cranking speed on the switchbox terminals for the wires that go to each of the coils. I guess you could try and test with a regular digital meter and see if you have any output at all. If no out put at all, then I would suspect the switchbox is dead.

 

[cowansauto]

Re: No Spark 1993 90hp Force (Sportjet)

Make sure the magnets under the inner circumference of the flywheel are intact and not broken or missing. Should be six of them.

Does your ignition system have a switch box? If so, you need to test the out put of the switchbox to the ignition coils. You need a DVA meter to test properly. You should see approx 200 to 360 volts at cranking speed on the switchbox terminals for the wires that go to each of the coils. I guess you could try and test with a regular digital meter and see if you have any output at all. If no out put at all, then I would suspect the switchbox is dead.

This is a nice replacement flywheel I recently bought off of eBay. I broke one of the magnets off of the original one that was on the engine when I bought it. Yes it has a switch box. Has the terminals for the coils, stator, trigger, kill switch, etc. I have a DVA meter on order. Hopefully it will be here in a few days. I read somewhere that You could multiply AC voltage times 1.4 to get close to dva readings.

Here's the link for the other manual as well that I've been using:
http://motorka.org/doc/mercury/service_manual/jet/SJ90_120_95xr_125xr_831996r1/sec2a.pdf

What's the proper way to test the coils with a DVA meter. One meter lead on each coil wire at switch box and the other on a good ground?

 

[jerryjerry05]

Re: No Spark 1993 90hp Force (Sportjet)

You check the stator for output??
Check the ohms through the stator?
You really need the DVA.
I doubt all 4 coils are bad???
I think Radio Shack might have a DVA adaptor if you cant wait.

 

[pnwboat]

Re: No Spark 1993 90hp Force (Sportjet)

Yes you can kind of "guestimate" the Stator/Switchbox output with a regular meter just to see if any voltage is present. But whether or not it's the correct voltage, you really need a DVA to be sure.

Since your resistance readings for the stator are within tolerance, I would not suspect that it is bad but it's always good to double check with a DVA. To test, check between ground and each of the stator leads (White/Green and Green/White). Disconnect the leads while testing. Crank the motor over and observe the meter readings. Make sure you have a good fully charged battery. If you have any doubts about the cranking speed, you can remove all of the spark plugs and the motor will spin a bit faster.

To check the output of the switch box, use basically the same procedure. Make sure the stator leads are connected to the switch box. Crank the motor and measure the voltage between each of the four terminals on the Switchbox that goes to each of the coils. You should see basically the same voltage as the stator output. If you don't have the proper voltage output to the coils, then most likely the switch box is bad.

One other thing, do you have an adapter between the SwitchBox and the Stator? A lot of folks refer to it as the "candy bar" adapter because it about the size of a Baby Ruth candy bar. The purpose is to reduce the Stator voltage going to the switch box. If the adapter is bad, you won't have any spark.

Here is a picture of the stator and the adapter.



http://www.ebay.com/itm/MERCURY-MARINER-FORCE-OUTBOARD-RED-STATOR-KIT-834949A4-/271038769813?pt=Boat_Parts_Accessories_Gear&hash=item3f1b2b6a95&vxp=mtr

 

[cowansauto]

Re: No Spark 1993 90hp Force (Sportjet)

One other thing, do you have an adapter between the SwitchBox and the Stator? A lot of folks refer to it as the "candy bar" adapter because it about the size of a Baby Ruth candy bar. The purpose is to reduce the Stator voltage going to the switch box. If the adapter is bad, you won't have any spark.

Here is a picture of the stator and the adapter.



http://www.ebay.com/itm/MERCURY-MARINER-FORCE-OUTBOARD-RED-STATOR-KIT-834949A4-/271038769813?pt=Boat_Parts_Accessories_Gear&hash=item3f1b2b6a95&vxp=mtr

Yes I have the adaptor box thing installed. Here's an actual picture of the side of my engine.


One thing though that I need verified: I had an extra ground wire that I ran to one of the bolts to one of the fuel recirculation ports. I am farily certain that this wire went there but not 100% for sure. I labeled it as "ground wire to fuel port screws" when I initially dissassembled the motor. Could someone look at there engine and verify that this is where it is supplosed to go. Of course if it's a ground wire, then as long as the area where it goes is a ground I guess it doesnt matter..??

 

[cowansauto]

Re: No Spark 1993 90hp Force (Sportjet)

You check the stator for output??
Check the ohms through the stator?
You really need the DVA.
I doubt all 4 coils are bad???
I think Radio Shack might have a DVA adaptor if you cant wait.

The ohms for the green/white & white/green wires coming out of the stator showed 680 ohms. My troubleshooting guide shows 500-700 ohms is what it shold show. The output of the stator is checked with the DVA meter correct?

Heck I've been waiting since I bought the boat first of July to get it done so I guess I'll wait unitl the correct meter comes in.

 

[pnwboat]

Re: No Spark 1993 90hp Force (Sportjet)

Yes a ground is a ground. Doesn't really matter where on the block the ground is actually connected, as long as it is securely attached to a the block.

Yes output of the stator is checked with a DVA meter. Checking output of the switch box to each of the coils is also done with a DVA meter.

 

[cowansauto]

Re: No Spark 1993 90hp Force (Sportjet)

ESI DVA meter came in today. If I can get up at a decent time before work tomorrow I'll post results using this meter!

Thanks for everyone's help!

 

[cowansauto]

Re: No Spark 1993 90hp Force (Sportjet)

Since your resistance readings for the stator are within tolerance, I would not suspect that it is bad but it's always good to double check with a DVA. To test, check between ground and each of the stator leads (White/Green and Green/White). Disconnect the leads while testing. Crank the motor over and observe the meter readings. Make sure you have a good fully charged battery. If you have any doubts about the cranking speed, you can remove all of the spark plugs and the motor will spin a bit faster.

To check the output of the switch box, use basically the same procedure. Make sure the stator leads are connected to the switch box. Crank the motor and measure the voltage between each of the four terminals on the Switchbox that goes to each of the coils. You should see basically the same voltage as the stator output. If you don't have the proper voltage output to the coils, then most likely the switch box is bad.

One other thing, do you have an adapter between the SwitchBox and the Stator? A lot of folks refer to it as the "candy bar" adapter because it about the size of a Baby Ruth candy bar. The purpose is to reduce the Stator voltage going to the switch box. If the adapter is bad, you won't have any spark.

Here is a picture of the stator and the adapter.



http://www.ebay.com/itm/MERCURY-MARINER-FORCE-OUTBOARD-RED-STATOR-KIT-834949A4-/271038769813?pt=Boat_Parts_Accessories_Gear&hash=item3f1b2b6a95&vxp=mtr

Battery is on charger. Disconnected both stator leads (green/white) and (white/green). Placed red meter lead on one of those and other clipped to engine ground. As I cranked the engine the meter never moved on either wire. Basically no change when testing the three coil wires that run to the switch box.

 

[emoney]

Re: No Spark 1993 90hp Force (Sportjet)

Probably a silly question, but it at least deserves to be asked I suppose: Are you sure the kill switch is functional, or have you tried bypassing it?

Outside of that, if the new meter gives you in-spec readings, sounds like the "candy bar" adapter could be bad? I'm not even qualified to ski the same lakes as these experts are, but having owned one I know how frustrating the electrics can be on these little motors, so I figured I'd throw a couple of questions out to keep the conversation flowing (and it keeps your thread on top). On the optimistic side, once you get this electrical issue solved, they're fun little motors inside fun little boats. Just get ready to practice an all new way of steering, lol. Good luck!

 

[cowansauto]

Re: No Spark 1993 90hp Force (Sportjet)

Probably a silly question, but it at least deserves to be asked I suppose: Are you sure the kill switch is functional, or have you bypassing it?

Yes I believe this was the step by disconnecting the black/yellow wire at the switchbox. As far as takin the switch out of dash to test, no I have not done so.

 

[pnwboat]

Re: No Spark 1993 90hp Force (Sportjet)

One other thing you need to check is the resistance between the Green/White and ground, and White/Green and ground. It should read "open". If you do read resistance, then the stator windings are shorted to ground and that will kill any voltage output.

 

[cowansauto]

Re: No Spark 1993 90hp Force (Sportjet)

One other thing you need to check is the resistance between the Green/White and ground, and White/Green and ground. It should read "open". If you do read resistance, then the stator windings are shorted to ground and that will kill any voltage output.

Thanks for the new suggestion. I'll check that in the next couple days.

 

[cowansauto]

Re: No Spark 1993 90hp Force (Sportjet)

I figured out what was wrong with the no fire situation....the switchbox was bad. I recieved the dial type meter that is uesd in the Mercury service manual and went thriugh the steps and found 0 volts on one of the test steps were there should have been alot more than 0. I bought a used CDI unit off of eBay, got it installed and now there's spark on all three but the engine would not go ahead and run. I'm going to make another post just on this new issue I believe.