sport jet 90 ignition (of course) indywolf

[indywolf]

Kend301 and other boat brainiacs,

Admired your dogged diagnosis of Chronomania's problem. Could you possibly lend me some help?

I have a 94 sport jet 90 in the 33000 serial number range. Same problem as usual: no spark. It ran fine when I parked it in 2004, but now it cranks but won't start.

It has the red stator and newer voltage regulator. Disconnected the yellow/blk wire-no spark. Disconnected the two yellow (voltage regulator-854515 1887 printed on case) wires-no spark. Disconnected all wires to the rev limiter (821889 A6 printed on case)-no-spark

Read some of Kend301s earlier posts and checked what I could:
Stator (green/white to white/green) 685 Ohms
Triggers each in the 1210-1250 Ohm range
Coil primaries .5 ohm each.
Voltage through the 5 amp fuse to the various black boxes.

Is there a way to test the switchbox thingy (xx2-7778A10 0963 printed on case) ?

Haven't pulled the flywheel, but I guess that is next.

Help!

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

Hi Indy , Be sure you have a good battery and also pay attention to the DO NOT RUN OUT OF WATER warnings !! You need at least 250 cranking rpm to fire the system . Do this test before you pull the flywheel.
The switchbox bias test is as follows :
Set voltmeter to 20 volts DC
connect red meter lead to good ground
connect black meter lead to White/black at the box
Crank engine , Volts should be between 2 and 10 volts.
if over or under the switchbox is bad.
If it passes , Pull the flywheel and check the magnets . I will do some research , there is another test not in the book that works , I just need to find it .

 

[indywolf]

Re: sport jet 90 ignition (of course) indywolf

Kend 301,

Thank you for the prompt reply. I will do the test you suggest and get back to you.

Incidentally, I wonder if anybody has opened up a switchbox to see what is inside. I had an intermittent problem in an Electromotive Tec2 (aftermarket fi and ignition computer) that I put on an old hot rod. I peeled away the potting compound, which was some sort of silicone rubber, and found a whole row of cold solder joints. It works fine now.

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

Kend 301,

Thank you for the prompt reply. I will do the test you suggest and get back to you.

Incidentally, I wonder if anybody has opened up a switchbox to see what is inside. I had an intermittent problem in an Electromotive Tec2 (aftermarket fi and ignition computer) that I put on an old hot rod. I peeled away the potting compound, which was some sort of silicone rubber, and found a whole row of cold solder joints. It works fine now.

I have never taken one apart but I suspect that it is as you suspect a custom junction block that probably could be repaired . I have never tried but if you do take yours apart post up what you find I would like to know .

 

[indywolf]

Re: sport jet 90 ignition (of course) indywolf

I checked the box as directed. The battery was good and the engine spun as fast as it ever did. The blk/wht-to-ground voltage was 1 volt, plus or minus about .05 volt.

I also checked the stator. Green/wht-to-white/green was about 198 volts, and yellow-to-yellow was about 6 volts. The trigger voltages were all over the place, but generally around .3 volts, I suspect because the trigger spike didn't coincide with when the meter updated the measurement. Also, using a cheap digital meter.

I guess this means the switchbox is bad, although I don't know why it would go bad while sitting in my yard under a tarp.Where is the best place to get a switchbox?

 

[indywolf]

Re: sport jet 90 ignition (of course) indywolf

Another question while wee are at it. I have looked around the net for a replacement switchbox. Mine is #332-77789A10. I see 332-7778A12 listed as the correct box for my engine on several sites, but they never cross refence it to my number. Is there an important difference between the A10 and the A12 models?

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

I Will cross the number later and post what I find .

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

Switchbox part numbers are as follows :
18495 a 12 is the mercury
114-4953 is CDI electronics aftermarket
The number you posted is for the old style ring and screw connectors , The newer ones have plug in connections. Please clarify which you have and I will confirm numbers .

 

[indywolf]

Re: sport jet 90 ignition (of course) indywolf

Mine has screw terminals. I also de-potted the circuit board for fun. If you cut around the perimeter of the case, then delicately drill a hole in the bottom of the metal case, just barely through the metal, and squirt some compressed air into the hole, the entire potted unit will detach from it's moorings and you can wiggle it out.

Once out, you can cut away the plastic face-plates that surround the terminals, and dig the rubbery potting compound out from between the components. The bottom of the circuit board has no components attached, and the potting compound just peels off. It took me about two hours, but I didn't have anything better to do.

As you can see, the unit consists of a big capacitor, six discrete semiconductors along with a few diodes, a few resistors and three small transformers. No processing electronics, I haven't checked the components to see what is bad, because I don't know what I am doing. Will give the unit to a friend who does and will report back.

Now I am going to try to download the photos I took.

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

CDI makes a ring type box that is only like $115.00 that works just fine , I need to go through my notes and find the part number , I will post it later

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

CDI part number is 114-7778 and is only like 90 bucks. It works just fine with ring connectors.

 

[indywolf]

Re: sport jet 90 ignition (of course) indywolf

Thank you so much. I will order one and see if it cures my problem. I will also report back on the de-potted board, although that will take about a week, since my electronic friend is currently out of state on vacation.

 

[indywolf]

Re: sport jet 90 ignition (of course) indywolf

Forgot to ask if anybody has any recommendations on where to buy this thing.

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

Iboats should have one , Just click on the boats parts tab at the top of the page and it is best to call them as sport jet applications are very misleading and also I got this part number straight from CDI and know one other that got one and it worked just fine.

 

[indywolf]

Re: sport jet 90 ignition (of course) indywolf

Just found the part at Tungsten Marine in Kenner, LA for $99, shipped. Will let you know if it works. If not, I have a lathe and am going to retrofit the damn thing with points and coils.

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

Easy does it , these things are more finicky than the prom queen , You will be on the water soon !

 

[gfa100856]

Re: sport jet 90 ignition (of course) indywolf

I have the same problem on a boat i just purchased. I replaced the switch box and it started up and then stalled out. I cleaned the carborators and it ran for a while and then stopped. I replaced the switch box again and it ran for a little while and then stopped. The second time I could not rev up the engine. I have no spark again. I still have some fuel coming out of the carbs too. I tested the resistence of the trigger and all three wires cam in at 1.2k ohms. I tested the stator resistence and it was around .500M ohms. What do i do next besides removing the flywheel wich i am doing this weekend. I order all new parts except for the adapter and the flywheel.

 

[kend301]

Re: sport jet 90 ignition (of course) indywolf

Welcome to I boats GFA , the first thing you need to do is open a thread for your boat and see the first thread in the PWC section and post test results .