MAXI Fuse Block Conversion for Datsun S30 Fusible Links
  Craig Borden  
 

None

 
 WARNINGS

THIS CONVERSION IS FOR OFF-ROAD USE ONLY. These instructions are listed for informational purposes only and as performed on a 1977 Datsun 280Z originally equipped with an external voltage regulator. Conversions on ALL other model years will vary and any conversion attempted is not the responsibility of Z Car Creations.

Your Z car's electrical system handles high amperage direct current.  Improper installation or use can cause injury, including fire, burns, and electric shock.  For use only in specified vehicles.
The components listed in this conversion have been designed to handle a maximum current rating of 110 amps, 12VDC.  Do not exceed.

This conversion is designed for an already functioning system.  Batteries and battery cables must be in good condition.  Do not attempt this conversion if your electrical system does not function, your battery is discharged, or there are shorts in your system or any of its components

  1. Disconnect Negative battery terminal. 

  2. Remove Battery cable positive terminal from Starter solenoid.  At the same time, remove second wire connected to positive terminal of solenoid.  Disconnect spade terminal from top of Starter solenoid.

  3. Disconnect all plugs and terminals from Alternator.

  4. Remove Alternator.  Retain Alternator belt.

  5. Remove lower alternator bracket from block by removing 2 bolts and 1 nut.  Retain the nut and bolts

  6. Detach fusible link assembly from electrical shelf.

  7. Detach electrical shelf assembly from fenderwell by removing 4 bolts.

  8. Unplug voltage regulator from wiring harness at provided connector.   Remove voltage regulator from electrical shelf assembly.  Disconnect any remaining connectors on the electrical shelf.  Remove electrical shelf from car.

  9. panmnt1.jpg (56438 bytes)Install Fuse center onto electrical shelf in the following manner. See picture for positioning information.  Position solid bus bar towards the top of the shelf, and the 4 separate bars towards the bottom.  Note - The bottom will have 4 Allen screws and 4 openings with 1 solid red wire attached.   The side of the fuse center that has the 2 red wires and the 80 amp fuse will go towards the front of the car.  Center the new Fuse center on side of electrical shelf assembly where old fusible link assembly used to mount.  Mark holes, and drill for new screws.  After drilling attach the fuse center to the electrical shelf by putting the screws through the screw openings in the fuse center, then slide the rubber insulating standoffs onto the screws.  push screws through drilled holes and attach self locking nuts to screws.  Tighten nuts until a slight amount of compression is noted on the rubber standoffs.  Do not overtighten.  Overtightening will cause the fuse center to bow in the middle, and could cause premature failure.

  10. Place electrical shelf assembly to the side.  Remove old electrical tape from wiring harness.  Start at the firewall below the battery, and continue until all wiring is exposed up to the alternator.  It is not necessary to continue past the alternator.  Make sure that all tape is removed from wires leading to fusible link assembly.

  11. flnum.jpg (8871 bytes)See picture at right.  Label only the wires that are white with a red stripe.  From the right fenderwell looking down, label the wire at position 4 as number 4.  Label the wire at position 3  as number 3.  Label the wire at position 2 as number 2.  The thickest white wire with a red stripe does not need to be labeled.  Cut all white with red striped wires 1/2 inch below bottom of fusible link block.

  12. Separate the white wire that comes from Starter solenoid positive terminal from the rest of the wiring harness.  Separate white wires that come from fusible link assembly from the rest of the harness.  Remove old fusible link assembly from car.  Old parts will not be needed and may be discarded.

  13. Locate white with red stripe wire that comes from the alternator.   Follow down the wire until it branches into 3 wires.  Note that all 3 branches are different sizes.  The thickest wire goes to the old fusible link assembly and can be ignored.  The thinnest wire goes to the old voltage regulator, and can be ignored.   The medium sized wire goes all the way straight to the firewall, and eventually connects to the fuse panel inside the car.  Label this wire as Main, and cut it 1 inch from connection with alternator wire.

  14. vrharness-numbered.gif (12734 bytes)Locate voltage regulator plug near battery.  Hold plug in the position shown.  Locate wire that corresponds to position 1.  Label this wire as L.  Cut wire 1 inch below plug.  Locate wire that corresponds to position 3.  This wire should be yellow.  Label this wire N1.  Cut wire 1 inch below plug.  Cut remaining wires 1 inch below bottom of plug.  These wires will not be needed.  Discard plug.




  15. tplug.jpg (2439 bytes)Locate the two wire "T" plug from alternator.  Locate yellow wire at the top of the "T".  Label this wire as N2.  Cut this wire 1 inch from "T" plug.  Discard "T" plug.



  16. Locate wires labeled 2, 3, and 4.  These wires are white with a red stripe.  Strip insulation 3/8 inch from the end of the wire.  Tin these wires with solder. 

TIP: Tinning involves heating the exposed wire and adding a small amount of solder.  Do not overheat wire.  This will cause the insulation to melt.   Make sure soldering iron is hot, and flow solder onto the tip.  Once the tip has molten solder on it, touch the exposed wire with the molten solder and tip.   After a moment, the wire should be hot enough to add solder.

  1. Install electrical shelf with new fuse center into car using 4 bolts.   Attach any auxiliary plugs that were removed during disassembly.

  2. panmont2.jpg (31445 bytes)Route wires labeled 2, 3, and 4 to the bottom of the fuse center.   Insert wire labeled 2 into the position shown in the photograph.  This is the first empty wire terminal connection next to the solid red wire coming from the bottom.   Insert wire far enough that it will make solid contact with the Allen screw.   Tighten screw until wire is crushed and cannot be moved.  Insert wire labeled 3 into it's corresponding position in the photograph.  This will be the opening directly under the 50 amp fuse.  Tighten as above.  Insert the wire labeled 4 into the remaining opening in the bottom.  Tighten as above.

  3. The following step involves options.  The purpose of this step is to make the electrical connection to your fuse panel inside the car.  This is accomplished by connecting the wire labeled Main to the supplied wire that is located at the junction of wire 1 from bottom of fuse center.  To locate this wire, follow the red wire 1 from the bottom of the fuse center until the junction is found.  Select the smaller wire at the junction. Label this wire New.

Options:

  1. Replace Main with New wire.  Use supplied wire, and route completely into car, making a final attachment on the backside of your fuse panel.   Old wire marked Main will not be used and can be discarded.  Pros- removes another wire connection where corrosion could occur in the future.  Eliminates the need to solder (although soldering is recommended at final connection to fuse panel)   Cons - Adds time and difficulty to the installation.

  2. Splice Main with New wire using Solder.  Cut new supplied wire 6 inches from the junction.  Strip insulation 1/4 inch from end and tin the wire.   Locate wire marked Main.  Strip insulation 1/4 inch from the end.  Tin the wire.  Slide heat shrink onto wire marked Main, and slide away from the end of the wire approximately 1 foot.  Join the two wires with solder.  Inspect joint for quality.  Joint should be shiny and smooth.  If joint appears dull, or solder does not appear to meld with the wire, resolder.  When satisfied with joint, slide heat shrink over joint, and apply heat.  Joint should be completely covered by heat shrink.  If not, apply electrical tape until it is.  Pros - Not as difficult as option A, but just as reliable.  More difficult than option C but more reliable.  Soldered connection will remain good over time. Recommended!  Cons - Can be difficult for those unfamiliar with soldering practices.

  3. Splice Main with New wire using Crimp.  Cut new supplied wire 6 inches from the junction.  Strip insulation 1/4 inch from end and tin the wire.   Locate wire marked Main.  Strip insulation 1/4 inch from the end.  Tin the wire. Slide heat shrink onto wire marked Main.  Insert wire marked Main into one end of 12 gauge crimp/butt connector.  Crimp.  Insert New wire into other end of crimp/butt connector.  Crimp.  Slide heat shrink over crimp connection.   Apply heat.  Joint should be completely covered by heat shrink when finished.   If not, apply electrical tape until it is.  Pros - Easiest of the 3 options.   Does not require soldering (tinning the tips is also optional).  Fastest installation method.  Cons - Least secure connection.  Crimped joints can corrode over time.  Crimped joints can become loose and intermittent over time.

Option B is recommended for long term reliability.  Option C uses a high quality connector and should be nearly as good as option B.  Option A removes the connection from under the hood and would provide the most reliable connection.

  1. Locate wires N1 and L.  Strip insulation 1/4 inch from end.   Tin the tips.

Options

  1. Connect N1 to L using Solder.  Slide heat shrink over wire L, sliding it away from wire end.  Join wires with solder.  Slide heat shrink over joint and apply heat.  If joint is not covered by heat shrink, apply tape.

  2. Connect N1 to L using Crimp.  Slide heat shrink over wire L.   Insert wire L into 16 gauge crimp/butt connector.  Crimp.  Insert wire N1 into other end of crimp/butt connector.  Crimp.  Slide heat shrink over connector.  Apply heat.  If joint is not covered by heat shrink, use tape.

  1. altplug.JPG (2978 bytes)Locate wire marked N2 and new alternator plug with two wires.  Using the figure to the right, determine which wire is number 1 by looking at the connector end of the plug, with the wires pointing away.  With the notch at the top, the wire to the right is number 1.  This will be used for the charge light circuitry.  Wire 2 is used for alternators that are not selt exciting.  Some alternators have this connection made internally.  This is used by the alternator to determine when to start producing voltage.  If you are unsure about your alternator, leave this wire disconnected.   After installation is complete, if alternator does not function correctly, connect this wire (number 2) to the positive output of the alternator.  If alternator functions correctly without this connection, clip wire 2 at the base of the plug.

Options

  1. Connect N2 to 1 using Solder.  Slide heat shrink over wire N2, sliding it away from wire end.  Join wires with solder.  Slide heat shrink over joint and apply heat.  If joint is not covered by heat shrink, apply tape.

  2. Connect N2 to 1 using Crimp.  Slide heat shrink over wire N2.   Insert wire N2 into 16 gauge crimp/butt connector.  Crimp.  Insert wire 1 into other end of crimp/butt connector.  Crimp.  Slide heat shrink over connector.  Apply heat.  If joint is not covered by heat shrink, use tape.

  1. Install new alternator bracket using bolts and nut removed in step 5.   Install Delco Remy Delcotron 10Si or 12Si alternator.  Install original alternator belt.  Tighten belt to manufacturers recommended specifications.

  2. Plug in new alternator plug used in step 21 into the alternator.

  3. Follow the big red wire from location 1 at the bottom of the fuse center.  This wire is the same one that spliced with Main in step 19.  Follow the wire until the end, which has a terminal connection.  Connect the terminal of this wire to the alternator output.  This should be the only terminal available on the back of the alternator.  Make sure you do not connect this terminal to any ground.

  4. Follow the other big red wire from the side of the fuse center.   This wire has no junctions, and ends in a terminal.  Connect this wire to the starter solenoid positive terminal.  Connect battery cable positive terminal to starter solenoid positive terminal.  With both wires on the post, attach nut, and secure both wires. WARNING, Battery should remain disconnected. 

  5. Plug in spade terminal at top of starter solenoid.

  6. Unplug and discard unused condensors from area of voltage regulator and alternator.

  7. Optional but highly recommended - If you have access to an ohm meter, test the circuit using the following instructions.  If not, conduct only test a.   Note, if any test fails, do not proceed.  Stop and retrace the steps, verifying all connections.  Damage to property and person could result from improper connections.  Do not connect the battery until all tests pass, and directed to by these instructions.

  1. Go though the steps, and verify each connection visually.  All needed wires will be connected at this time, and should be in their correct location.   If not, correct.

  2. Set your meter to Ohms, and place one test lead on ground, and the other on the starter solenoid positive terminal.   If meter reads infinite (no continuity), proceed to next test.  If meter reads anything other than infinite, retrace steps to find where the improper connection was made.

  3. Set meter to Ohms, and place one lead on starter solenoid positive terminal, and the other lead on the alternator main output.  Meter should read 0 Ohms (maximum continuity).  If meter reads 0 Ohms (plus or minus 1 or 2 ohms), proceed to next test.  If meter reads infinite or high resistance, retrace steps to find and correct problem.

  4. With meter still connected as in test b above, remove the 80 amp fuse from the fuse center.  You should see a transition from 0 Ohms to Infinite Ohms.   If this test passes, smile and proceed to next step.  Good job!  If step fails, retrace steps to find and correct problem.

  1. Examine wiring harness for loose and unused wires.  Remove any wires from harness that have no connection on either end.  Some wires will be left over from this process, and will remain in the harness.  These wires are grounds, and are no longer needed.  If desired, the large ground from the old alternator may be connected to the frame or block using a suitable bolt.  Unused smaller grounds can be safely taped into the harness.  Form wires in harness into the desired shape, bundling them together. 

  2. When wires are in the desired shape, begin taping wires.  Start by using small strips 1 foot apart to keep the wires together.  Then tape from the ends of the branches towards the main harness.  Tape the wires from the bottom of the fuse center to the main harness.  Tape the wires from the starter solenoid positive terminal towards the main harness.  Tape the wires from the Alternator to the main harness.  Now tape the main harness.  Tape wires from the firewall to the alternator.  Make sure to wrap tape over the tape ends from the branches.  While taping, try to overlap at least half the width of the tape.  Be thorough.  Leave no exposed wiring in the harness.  Leave enough exposed wire at the ends of the branches to facilitate removal in the future.  Example, leave 4 inches unwrapped wire at the alternator to allow for ease of alternator replacement.

  3. Use supplied tie wraps or existing wire tie downs to secure harness to chassis.  Make sure harness is not allowed to move or rub against metal parts.

  4. Connect Negative battery terminal.  Be alert for any sign of a short.  If short is present, disconnect battery immediately! 

  5. From inside car, examine voltmeter.  Gauge should read battery voltage.  Turn key to "ON".  Pull emergency brake.  Verify that both the "BRAKE" lamp and the "CHARGE" lamp should turn on.  If not, verify steps 20 through 23, and correct.

  6. Start car.  Rev engine to 1500 rpm.  Charge lamp should extinguish, and voltmeter should rise, indicating a charging state.  Allow engine to idle, and verify that alternator functions correctly.  Some alternators don't begin charging until a preset rpm has been reached.  If you desire the alternator to charge at all times, either change pulley sizes to a smaller pulley, or increase engine idle to a higher rpm.

  7. Enjoy a worry free charging system.  Get some decadent electrical appliances (toaster oven, laser gun, electric fence) and attach them to your Z with no worries.  You've got the power!