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Just wondering if anyone knew how to fix a spark issue I'm having? I'm new to the luv scene but so far I'm loving it. I have a 75 with the stock Isuzu 1.8 and I just replaced the coil and resistor. Engine turns over but still no spark from the coil. Any suggestions??? Thanks for the help.

Check your wires, this is a gen wire diagram, but the info is the same. Hope this helps-

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I have checked every wire that runs to and from the ignition and coil and still no spark. Don't know what to do.

Have you measured for voltage at the ''+'' terminal of the coil? While your wires may be in good shape, the fuse boxes are one of the worst trouble makers in the truck. The pieces are riveted together and sometimes corrode and fail to transfer power to the wires. You may have power in, a good fuse, but no power to the wire.

Yea I check the coil and it's at 11.92.what do you mean the pieces are riveted?

The things that hold the fuse are riveted to the terminals for the wires. Current may not make it from one terminal to the fuse, or from the fuse to the other terminal.

I'm stumped. I checked all terminals on the fuse block and still no spark. I dont know what is wrong with it.

How are the points and condensor? They must be in good shape and gapped correctly. Remove the cap, have someone crank the engine and make sure the distributor is rotating.

Everything is moving freely and I traced all wires from coil to ignition and no spark. What to do?

Here is out to check out the coil: Remove the center cable from the coil, plug in a spark plug cable you borrow from the cap, plug in any spare spark plug you have laying around and lay it against the block to ground the case. Remove the wire/wires from the coil - terminal. With the key on engine stopped, ground and unground the - terminal with an insulated jumper wire--plug should spark every time you do this. If this works then the only place left is the points, condensor, wiring broken somewhere in the distributor, etc. The points job is to do exactly what you did with grounding and ungrounding the coil. Look for a broken wire ground from the points mounting plate to the distributor body.

Listen to EGG. He got mine running! Question for you. Is everything stock? I ask because I changed to a MSD Blaster II coil and it requires the resister THEY recommend. The resister I originally tried was generic which was my problem.

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I've never been wrong! Once I thought I was, but I was mistaken.
Rick
Loranger, La
1980 Stepside LUV (Again)

Yes every thing is stock except the carb, it's a redline. I bought a new resistor and coil the other day and put them on and still no spark. The only wire that wasn't plugged in was on the distributor. I plugged it in and tried to start it and my resistor started smoking. I checked the power to the resitor and coil and they are both at 11.9. I will try egg's suggestion after work. Hope it works.

That's odd, if you have a ballast resistor for your coil, your coil should not be seeing 12v, but closer to 8 (if I remember correctly).

The coil should not be connected directly to a 12v like in the picture. It should be (switched) 12v source -> ballast resitor -> coil +.

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1975 Project LUV
It's ALIVE!

It's a Chevy diagram, early Chevys had resistor wires instead of ballast resistor. Drawing is labeled as so.

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So I did what Egg said and no spark? Wonder if I got a dud coil?

It took me 3 tries to get an alternator that worked from AAP. I will say they were under warranty from the one I bought 10 years ago. If you had an ohmmeter, you should get a reading from the + to - terminals.

So I hooked my multimeter to the coil lead that goes to the cap and cranked it and had plenty of power, just no spark. I was wondering if the capacitor on the distributor is dead and not allowing spark to be created? Any ideas??

You can do a rough check on the cap with an ohmmeter. Check from the lead to the case. You should initially get a reading, but quickly climb off scale. If no reading at all, or a steadin reading, it is bad. If you have an old one laying around, you could try it. They really seldom go bad.

Just an FYI on the resister. I installed the one recommended by MSD for my Blaster
II coil and still get a 12 volt reading! Don't understand it, but the truck is still running.

_________________
I've never been wrong! Once I thought I was, but I was mistaken.
Rick
Loranger, La
1980 Stepside LUV (Again)

I have tried everything I could think of. I tested the whole system and put a new cap and rotor on the damn thing and still no spark. I want to push it off a cliff.