Team Chevelle banner
1 - 20 of 22 Posts

·
Premium Member
Joined
·
243 Posts
Discussion Starter · #1 ·
I posted this in Engine section first but thought this might be more appropriate.

I'm trying to start my 66 396 project car for the first time. It's not really a complete car but is probably drivable in a few months. I'm working with only the engine wiring harness and I'm using a remote starting switch. The engine's turning over, but I'm not getting spark at the plugs. I used a test light and I have current at the + side of the coil and the plug wire from the coil to the distributor. But I don't have current when I test the plug wire ends.

I tested with a voltmeter on both sides of the coil and I'm getting 10V. I don't get any spark though from the plugs or any volts when I ground the wires.

Is there someway to test the rotor/cap/distributor, it seems the problem is in there.

Am I missing something here. Any help would be appreciated.

Thanks

Corey
 

·
Registered
Joined
·
7,758 Posts
First check and see if you are getting spark out of the top of the coil. This is a point in the circuit before the cap and rotor.
Sounds like the coil primary is not open because you see 10 volts on each side. When the points are closed, the (-) side of the coil should go to 0 volts. One side of the points goes to coil (-). The other side of the points is ground. This ground-no ground-ground-no ground action of the points "chops" the 10 volts on the coil primary and puts out a high voltage spark out of coil secondary. (The large center lead on the coil).
 

·
Premium Member
Joined
·
243 Posts
Discussion Starter · #4 ·
Well I'm checking the wire out of the top of the coil with a test light (my volt meter went south) and I'm getting continuous current when I spin the distributor.

Is there any way to test the points, condensor, anything inside the dist.

Thanks

Corey
 

·
Registered
Joined
·
7,758 Posts
If you unplug it at the distributor, hold the center wire of the coil near ground, you should get a spark. The same spark one would expect if you hold a plug wire to ground.
 

·
Premium Member
Joined
·
243 Posts
Discussion Starter · #7 ·
No, I don't get a spark.

But if I run a wire from battery(-) to coil(-) and touch and release it, I get a spark when I put the coil wire with a plug near ground. It looks like a faint spark, but a spark nonetheless. I guess that means the coil is good, I think.
 

·
Premium Member
Joined
·
6,740 Posts
Looks like John as left the building. I'll try to carry on until he returns.
I wouldn't expect the test light to be as bright when testing the coil output. The voltage is very high but almost no current. Need current flow to heat the bulb filament to make it glow.
Sounds like coil is ok based on your last test. Now you need to trace the - side of coil back to points, thru points then to ground. You can use your test light. One side to bat + other side to base of points, which should be ground. Then output side of points, while they're closed, then - side of coil with points closed. Actually that's tracing it forward not backwards but you get the picture. Leave ignition switch off during this so you don't burn something up.
 

·
Registered
Joined
·
1,761 Posts
could it be possible that the distributor is not grounded (not getting grounded to the block from grease or the gasket)(just a wild guess)
or are the points not completely closing?
 

·
Premium Member
Joined
·
6,740 Posts
Originally posted by Tom's 68 conv:
could it be possible that the distributor is not grounded (not getting grounded to the block from grease or the gasket)(just a wild guess)
or are the points not completely closing?
Certainly a possibility, I think grd is what he's missing, question is where. Should get grd if it's clamped down tight thru the clamp, should.
 

·
Premium Member
Joined
·
243 Posts
Discussion Starter · #11 ·
Actually I have the distributor in pretty loose, just enough not to pop up when I turn it over. I didn't realize that the distributor grounded through the engine block. I thought it either grouned to the condensor when points are closed and the the plugs when points are open. Anyway I'll try clamping it down harder.

When I trace it back from the coil(-) to points do I have it turning over or not. It's a fresh engine and I don't know how long I can keep turning the engine over and not hurt my cam. I pre-oil it ever once in awhile with the pre-oiler tool but don't know if thats enough.

Anyway tomorrow morning I'll try to test some more with the suggestions posted already. The points are definately closing and opening enough. I replaced the condensor. What else is there really? This one has me really stumped.

Thanks so much for all the replies so far guys

Corey
 

·
Premium Member
Joined
·
6,740 Posts
No you do not need to turn the engine over. You do not need to have the ignition on either. Just hook one side of your test light to bat + and then connect the other to the base of the points. If you have grd to the points the light will light. If that's ok then crank the engine by hand or adjust the points until they are closed. Check the other side of the points, if that's ok then check the - side of the coil. Hopefully you will find that you do not have grd at one of those spots because I think that is your problem.
 

·
Premium Member
Joined
·
243 Posts
Discussion Starter · #13 ·
Well I tried check for ground on the distributor last night and I do get a ground connection up to the points. The base of the points I get a ground but not on the other side. The points are closed. I guess this means the points are bad, but they're brand new.

Pretty slick way of diagnosing this problem. Thanks Much

Corey
 

·
Premium Member
Joined
·
243 Posts
Discussion Starter · #15 ·
I'll try to file the points down and see what happens. I guess I should replace them. I was looking at them and they have a little burn mark on the base but nothing big. You would think it would at least let a little current through. It has been sitting for about 3 years undisturbed.

Points...what am I thinking going all original. Thats why I have pertronix on my 71 daily driver. Never had to even take the dist cap off in the last 40,000 miles.

Corey
 

·
Premium Member
Joined
·
6,740 Posts
Ok new points and 3 year old points are 2 different things, even if they haven't been used much. Once they've been used at all the corrision process starts and will continue given enough dampness/humidity.
 

·
Registered
Joined
·
7,758 Posts
Yeah, sounds like the place to fix. Even if the distributor is loose, it should still get a ground through the shaft. Explains why coil (-) was always showing 10 volts.
 

·
Registered
Joined
·
235 Posts
This may not be the problem in this case ( more then one problem ) but I have said many times Hot wiring a car or using a jump starter switch button with the key off may burn out the ign. sw.
 
1 - 20 of 22 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top