Recently, I purchased a 1973 Toyota FJ40 with the intent to rebuild it with my 14 old Son as a project car. We have a spark problem that has gotten both of us scratching our heads. I have replaced the starter solenoid, ballast resistor, rotor button, and rotor cap. Also, we replaced the coil, condenser, and threw a new set of points in it ("properly gapped"). I have checked all fuses, checked for voltage and continuity with a multimeter, reset the timing. The car runs, "sometimes" but seems to have a mind of its own. AT one time we had it running; rough I might add. We made adjustments to timing and carbourator and it seemed to get slightly better but nowhere near to perfect. At one point we found that #1, #3, and #6 were not firing; now nothing is firing. It's slightly frustrating. Also, I was thinking about worn lobes on the distributor, which would affect spark -right? I was wondering if you had any ideas that perhaps you think I ought to try?
Spark, No Spark, Spark, No Spark - Ugh! HELP (1 Viewer)
- Thread starter Richard Kook
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Check distributor shaft bushing for slop. Measure plug wire resistance. Verify integrity of electrical connections from ignition cylinder to
distributor. ( bright shinny metal with lectrical grease).
If that don't werk I'll give 25 dollars for buggy as is.
Ballast resistor should reduce voltage at points to 6V when engine is running. During starting a terminal on starter solenoid provides 12V
to coil. ---I thimk--
distributor. ( bright shinny metal with lectrical grease).
If that don't werk I'll give 25 dollars for buggy as is.
Ballast resistor should reduce voltage at points to 6V when engine is running. During starting a terminal on starter solenoid provides 12V
to coil. ---I thimk--
S4Cruiser
SILVER Star
You've probably already done this...but rechecking, cleaning and confirming good grounds never hurts.
Is your new coil consistently sending voltage to your dissy? Your coil-dissy wire could be failing.
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- #5
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- #6
Thank You. I will go over again.
If your new coil is producing spark, but you don’t see spark at the dissy, try a new wire. In fact, I’d replace all plug wires, including the coil-dissy, if you do t know how old they are.
Recheck your points to insure they are clean between the points and base also check the wire connection Also check your rotor and cap is setting down completely
JP
JP
A good way to clean points is fold a dollar bill in half, long way is best, and with points closed slip the bill between the contacts and slid it back and forth a few times. Never use emery paper.
Loose wires, bad grounds would be my first guess. A worn dist shaft is usually accompanied with back firing.
JohnnyC
Long ago TLCA# 2231
73' was using a fuse to the coil afaik ...same as or similar to my 74'
@Coolerman would know for sure
... check it could be a bad fuse (yes you can have this without it being blown) or fuse block issue... clean it up and replace fuse
did you check that the power is constant when its running (or trying to) or cutting out to the coil ... could be a ignition switch
Or wires to the coil from switch
BTW the button is in the distributor cap ... sooooo just cap and rotor
@Coolerman would know for sure
... check it could be a bad fuse (yes you can have this without it being blown) or fuse block issue... clean it up and replace fuse
did you check that the power is constant when its running (or trying to) or cutting out to the coil ... could be a ignition switch
Or wires to the coil from switch
BTW the button is in the distributor cap ... sooooo just cap and rotor
The brute force way to check the low voltage circuits is to connect a jumper wire from the + battery to the + coil and from the - coil to the points terminal. Be ready to start the engine when you connect the + wire, and don't leave it connected for very long, the coil will get hot.
if it fires, one of the low voltage circuits is bad. With the jumpers still in place, disconnect one jumper at a time to identify which circuit is in trouble.
If it doesn't fire, use a volt-ohm meter to check the distributor grounding. With the wire to the distributor from the coil disconnected, and the points open, there should be zero ohms from the terminal to the distributor plate. With the points closed, there should be no resistance from the post to the plate, and to the distributor body, and to the negative battery post.
if it fires, one of the low voltage circuits is bad. With the jumpers still in place, disconnect one jumper at a time to identify which circuit is in trouble.
If it doesn't fire, use a volt-ohm meter to check the distributor grounding. With the wire to the distributor from the coil disconnected, and the points open, there should be zero ohms from the terminal to the distributor plate. With the points closed, there should be no resistance from the post to the plate, and to the distributor body, and to the negative battery post.
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- Thread starter
- #13
Thanks for the advice. I will eventually figure this thing out. $25 sounds like a real bargin' ("for you")
Thanks but I am keeping it. After all, it is a father son project.- Thread starter
- #14
Your right! It doesn't hurt to check the grounds. I will over them again. At this point, I am thinking it may possibly be a short through a worn or broken wire.
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- #15
If I recall, I don't remember seeing a pressure spring. I will go check it out over the weekend. Thanks for the tip.
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- #16
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- #17
I will look at it this over the weekend. Thank You very much for the advice!
