CDI 174-5721 Installation And Troubleshooting Manual

This unit replaces the following P/N's: 855721A 4 and 855721T 8.
Warning! This product is designed to be installed by a professional marine mechanic. CDI Electronics cannot be held liable for
injury or damage resulting from improper installation, abuse, neglect, or misuse of this product.
THIS STATOR IS DESIGNED TO BE USED WITH THE FOUR MAGNET FLYWHEEL. PLEASE VERIFY THAT YOUR FLYWHEEL HAS
FOUR MAGNETS, NOT TWO, WHEN INSTALLING THIS STATOR. IF YOUR FLYWHEEL HAS TWO MAGNETS, THE ENGINE YOU
ARE WORKING ON HAS ONE OF EITHER TWO OLDER DESIGNED IGNITION SYSTEMS AND THIS STATOR WILL NOT FUNCTION
AS DESIGNED!
1. Disconnect the Negative battery cable.
2. Disconnect the old Stator from the Switchbox.
3. Remove the flywheel according to the service manual for your engine.
4. Remove the old Stator and save the original bolts.
5. Check for signs of rubbing on the old Stator and the inside of the flywheel.
6. Using the original bolts, install the new Stator with a good thread locker applied to the bolts.
7. Connect the Green/White and White/Green Stator wires to the Switchbox.
8. Reinstall the flywheel according to the service manual for your engine.
9. Reconnect the Negative battery cable.
NO SPARK ON EITHER CYLINDER:
1. Disconnect the Black/Yellow stop wire AT THE SWITCHBOX and retest. If the engine now has spark, the stop circuit has a fault. Check
the key switch and harness.
2. Verify the Flywheel has Four magnets and not Two. The older ignition systems has a Two magnet Flywheel and this Stator will not
work.
3. Inspect and clean all engine and ignition ground connections. Make sure the Switchbox and Ignition coils are grounded properly.
4. Check the cranking RPM. A cranking speed of less than 250 RPM may not allow the system to spark properly. This can be caused by a
weak battery, dragging starter, bad battery cables, or a mechanical problem inside the engine.
5. Check the ignition system resistance and DVA as given below:
Read from
Green/White (Stator)
White/Green (Stator)
Green/White (Stator)
Brown/White (#1 Trigger)
Green/Yellow (#1 Primary) Engine Gnd
Green (#2 Primary)
7. Check the DVA on the Black/Yellow kill wire coming out of the Switchbox. You should have a reading of at least 150 DVA or more. The
Stator and Trigger should be connected to the Switchbox for this test. If you do not, check the DVA on the Stator and the Trigger. If the
DVA on the Stator and Trigger is good but the DVA on the Black/Yellow Kill wire coming out of the Switchbox is low, the Switchbox is
likely faulty.
8. Swap the Green/White and White/Green Stator wires and retest. If the problem moves, the Stator is likely faulty.
9. Using a set of jumper wires, cross connect the Brown/White and Brown/Yellow Trigger wires so that you have a Brown/White
connected to a Brown/Yellow. If the problem moves, the Trigger is likely faulty. If the problem stays on the same cylinder, the Switchbox
is likely faulty.
10. Check the flywheel magnets for cracked, broken, or loose magnets.
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Rev C • 6/19/2023
Installation and Troubleshooting Guide
This installation is to be completed by an Authorized Dealer or Professional Service
Technician. For questions regarding installation or warranty, call CDI Tech Support
at 866-423-4832. Do not return to the Dealer or Distributor where the part was purchased.
Contact CDI Electronics Directly for Return Material Authorization.
CDI P/N: 174-5721
INSTALLATION
TROUBLESHOOTING
Read to OEM Ohms
370-445 Ω
White/Green (Stator)
Engine Gnd
Engine Gnd
650-850 Ω
Brown/Yellow
Engine Gnd
CDI Electronics, LLC • 353 James Record Road SW • Huntsville, AL 35824 USA
www.cdielectronics.com
CDI Ohms
310-385 Ω
Open Open
Open Open
650-850 Ω
- -
- -
• Tech Support: 1-866-423-4832 • Order Parts: 1-800-467-3371
Page - 1 of 2
DVA Connected DVA Disconnected
150 V Minimum 150 V Minimum
150 V Minimum Less than 2 V
150 V Minimum Less than 2 V
4 V Minimum
150 V Minimum 150 V Minimum
150 V Minimum 150 V Minimum
4 V Minimum
QF-358