97 GT 40 running great then died

[MDGAY]

Morning! my 97 ski nautique was running great and after dropping a skier went to return to skier in the water and swinging back end of boat around went to go to reverse and engine stalled and wouldn’t restart. Almost like the safety kill switch was released but that is bypassed
engine getting gas and have voltage (10.5vdc) at coil but no spark. Engine was running strong just prior, stalled and now engine cranks but no spark….
thoughts?

[SilentSeven]

If I may kindly suggest....search the archives. There's more posts than you can imagine on GT-40 run problems and how to triage and diagnose.

[MDGAY]

I have done a bunch of research, and checked a lot of the points that the site recommends and it brought me to the coil side of things I have 12VDC going into my coil (purple wire to ground when key in on position), 10.5VDC coming out of the coil to the distributor cap. I disconnected the wires from the coil and did the resistance checks as suggested in the PCM owners manual and both sides of the coil check out mid specification for resistance. I had a little build up on the contacts inside the cap, cleaned those off but still no spark. The Rotor is turning as well. Is there anything else that keeps the spark from happening once power gets to the cap? Does that PIP sensor keep the engine from firing and would that be a sudden failure if it were to go bad? Just looking for some next steps. This site is a wealth of knowledge and history thanks for making it happen

[SilentSeven]

The distributor has a hall sensor that triggers the spark. If you have no spark but power to the coil, that could be the problem. My 97 had run problems that were solved by installing a rebuilt distributor.

https://www.planetnautique.com/vb5/f...e-replacements

[MDGAY]

I just wanted to close off this thread with what worked for me in case anyone runs into the same situation with thier boat.

• Boat: 1997 Ski Nautique, GT40 5,8L, 1550 hours. Runs great
• Symptom: Running strong pulling a skier, went around to pick them up, went from forward to reverse on throttle, engine died like someone turned the key switch off.
• Subsequent restart attempts were unsuccessful. Engine would crank over but not start. Needed a tow....

Troubleshooting steps performed (after getting towed in)

1. Verified gas delivery - Turned key on, heard gas pumps priming, plugs wet with gas after cranking.
2. Verified no spark - Took plug out of cylinder, no spark
3. Went to GT40 PCM User manual that I found here: https://www.planetnautique.com/Corre...e%20Manual.pdf
4. Leveraged "Section 3, Diagnosis" and went to the table on page 72 "Symptom Index"" and took the "No Start/Normal Crank path" (Chart 4)
5. Since I verified gas delivery and I didnt have access to a Start tester I went to section 3F to focus on the ignition THI issues.
6. Started at test 3F1 and followed all test results, making my way down the list, checking voltages, resistance as suggested in the steps
7. Got to step 3F1-13 where you needed a Rotunda tester test out the PIP or TFI sensor. Since I didn't have the tester i disconnected the TFI module and took it to the local Advanced Auto Parts.
8. They used the part number cross reference provided in the forum and came up w/ a CarQuest part number of CBE-1007 ($63)
9. Installed in boat, started right up.

Key takeaway:

1. Follow the diagnostic path's found in the PCM module. Step by step, saves you lots of money, and if you don't have a tester as suggested there is still a way to test things out, our in my case take a gamble on a $63 part.
2. Most of the TFI failures found on this forum behaved differently (Boat is running, stops working, engine cools down, boat starts again, pattern repeats) Mine just failed.
3. Did all of my tests with a digital voltmeter you can get most anywhere. (VDC and OHMS/Continuity tester)
4. This forum is awesome - If not for the helpful suggestions, documentation & manuals, past posts I wouldn't have enjoyed an awesome sunday morning Ski
5. If this forum helps you solve your problem make sure you go back and finalized the topic thread so others can benefit from your troubleshooting steps and outcomes. Lots of threads just die w/ no discernable outcome..

Thanks again for all the assistance.