75 Cranks - No Start - No Spark

[Viperwolf1]

Probably bad stator. You can replace it by itself but it probably isn't much cheaper than the whole distributor.

 

[danh25]

Hi there!

Update on this one just in case someone can help or someone finds this thread later. Now I am getting just a tiny little weak spark from the coil.

History:
Out of no where, Bronco would not start (after installing new headlights)

Walked though a lot of help above and have pretty much replaced the whole ignition system.

1. Replaced the coil and ignition module before do much diagnosing.
2. Used the Mitchell manual suggested by viper and though I had a bad distributor. So I replaced the distributor. This took forever, I had a lot of oil shaft problems. Finally got it in and have it very close to TDC, etc (I think...all new to me).
3. Also replaced the starter solenoid because it looks pretty beat up and I saw some burn marks on the positive post.

Now, when I crank it I get a very very weal spark when I put a spark tester between the coil and the distributor. Like just a little blip...no spark at the 1 plug. I have nothing to compare it to but it looks very weak to me.

Any ideas at all?

 

[Keek]

Off the top of my head and remembering from decades ago,

Check rotor bug and check cap to ensure it's not cracked, fouled and causing a short.

Spark should be a sharp snap, not 'weak'.

Check Coil to Distributor Wire. A bad coil wire to distributor can cause no spark.

 

[danh25]

Add new cap and rotor to the mix. That is pretty much an entire ignition system change out.

I am using one of those spark tester light things. Something that is interesting it the 'weak spark' that I think I am getting only comes right when I bump the engine...it does not pulse at all. So I am not sure that is even a real spark or just power getting to there.

Pretty desperate at this point and any pointers would be appreciated.

To recap.

Started just fine previously. Changed out some headlights...and tried to start it a few days later and it cranks but no spark.

Replaced the:
Coil
Distributor, Cap, & Rotor
Ignition Module
Starter Solenoid
Battery is good and it even has a new shiny ground cable

The parts that I could have messed up are..
First time replacing a distributor but I think it's good to go. From what I understand, if I jacked that all up it would just run terrible but I would still get spark right?

When getting a new ICM - I got it from autozone. It looks like it has a blue grommet and not the green. I don't think my old one was really ever bad but I have tried both in there.

 

[Viperwolf1]

Blue grommet is for '76 and later wiring. Won't work with '75 wiring. Take it back and get the right one.

 

[danh25]

Thanks Viperwolf1!

I got the correct green grommet one in and no changes.

I think that is pretty much 100% of the ignition system beside wires but since I am not getting a good spark from the coil I would guess that it is something before that.

What's next?

 

[ol gray mare]

Shot in the Dark

Just a shot in the dark; back in the '80s I had a similar problem with my 1970 (still had points then). The ignition switch was letting the engine crank, but not giving spark to the ignition. New switch and she lit right off.

 

[danh25]

thanks Gray!

Is there a way I can test this without just replacing it?

 

[danh25]

Also I have been using a remote starting switch...I would imagine that takes the ignition switch out of the mix. Correct?

 

[ol gray mare]

Do you have the switch on run when you use the remote? If so, I'd think it would eliminate the switch not supplying power on start. Might try to hot wire it and see.

 

[danh25]

Yes, switch set to on. Then the remote switch connects to bat pos and to the Ignition side of the starter solenoid.

 

[gr8scott]

Might try to hot wire it and see.

X2, run a jumper wire from BAT+ to COIL+ and then try the remote starter.

 

[danh25]

Can you be more specific? I suck at this stuff.

Do I leave the current wire on the Coil+?
When I crank it, what am I looking for?

Thanks

 

[ScanmanSteven]

Just add the jumper from the +battery to the +coil. This way you're bypassing the ignition switch, so what you're looking for is a running Bronco. Sorry, had too.