The Stovebolt Site Forums The Shop Area Engine Shop I'm Baffled,Won't Start, Need Help

It ran just a month ago,which is only saying I'm not trying to start this 52 chevy, 235 ci and never heard it run before.
So here's what I got. I have very little spark out of the coil,the spark will not jump a gap 1/16 in and looks so weak I was tempted to hold the wire just to feel what it would do.
Points/cond,cap,rotor,ign wires are new which were put in and I ran it 4 or 5 times after that.
I cleaned bat post again,connection at starter and still the same weak spark.
So then I hot wired it to eliminate any voltage loss in the primary ign circuit- 6v straight to coil.
Then I bought a new coil, cause I can't test the coil and still the same weak spark.
The only thing I don't have is an 8 volt battery which was dead when I got this truck. I put in a 6v, I didn't think it needed an 8v. Ummm, 2 more volts,think that would make it start.
I'm baffled, what do you guys think ?
Dan

Sounds like maybe a bad ground on engine. Is it grounded well? Engine to frame/cab? Battery to frame/cab?

You might try to jump it off with a 12 volt to see if the weak batt is the problem. I assume you know it is getting fuel. What about compression, got any?

Dan,

Sometimes the spark can fool you! It looks weak but can be adequate to start and run the engine.

Your battery should have clean cables and be fully charged. There should be nothing to 'jump around' in regards to your ignition system...when the key is ON, battery voltage should make a bee-line to the coil.

Does the engine POP at all! if you squirt some fuel or starting fluid into it will it POP at all. With all the mechanical stuff working right, you still need fuel AND spark! Make sure the ignition system is dry, including the stuff under the distributor cap.

If the points aren't adjusted properly, the coil can't saturate long enough and it can result in a weak spark.

The bottom line is, if you squirt some juice down the carburetor and it pops, the ignition is OK and you might be dealing with a carburetor or fuel supply issue.

Do some more digging and let us know what happens. Good luck.

Stuart

Okay I forgot a couple of things, I grounded the dist. just to make sure, and I did give it a blast of ether just to see if it would pop,cough, sputter,but nothing. Just cranks and cranks.

As far as comp., no I didn't take any readings cause I just assumed if it ran before it could run now or at least start or make a noise like I think I can start.
Dan

If the system voltage drops enough when it is cranking, the spark will be weak. I would try powering the coil separately from say a battery charger and see if you get different results. If it starts for you then you have to look at why the voltage is low.

I would stay away from the ether it could put a hole in a piston. Instead you could use WD-40.

Hey There,

are you running a ballast resistor in series before the coil?

It could be that this resistor is bad.

Simple and obvious: might the engine be flooded by now? You could pull a plug and see if is "wet" inside.

Can you do a compression check? Maybe the rings are binding to the pistons since it been sitting a while and your compression could be nil.

Do you have the right point gap? Should be .019" I think.

How about the firing order? Timing? Does the dizzy point to the #1 plug when the engine is at TDC?

Keep us informed,
Elias

Sounds like it may have a bad condenser,cheap enough to try a new one.

Turn the headlights on. If they're nice and bright, you should have plenty of juice all around. Sometimes those replacement, bolt-on terminal clamps just won't do it and you gotta break down and buy some proper wires.
My experience is that these engines can lose compression pretty fast. I've been in situations where: It started fine last month. I know it's got compression! And lo and behold ....Check compression. Of course, you gotta have plenty of juice to the starter to do that ....
And if you've been checking plugs and distributor a lot, remember how easy it is to "replace" the wires to the wrong cylinders. I've, ah, done that a time or two.