Post-rebuild no spark
 

Post-rebuild no spark

Here’s the checklist:

1. Engine cranking normal, pulley turning normal, battery excellent.
2. Will not start
3. No spark at plug wires
4. Confused and still can’t sort out plug gap and timing. (and the rotor orientation)
A. Tried to install distributor as before see pics below which are showing the distrib. before removal for rebuild
B. Confusion in identifying #1 notch or is it the number marked on the distributor? See pic no.2 as I have a number "1" inscribed on the side of the distributor (can be seen to the right of the wire connector), which is confusing the issue.

Even more confusing in Haynes page 85 states "on some distributors the no. 1 firing position is already marked"

C. I don’t know whether the rotor should be pointed at a "notch" or #1 on the dizzy side. Should there still be spark regardless?
D . Set point gap
E. I’m fatigued as I’ve tried testing CD box (which ran fine before rebuild), swapped coils, changed gap width, etc., tried pulley at 5 BTDC, and then 30 BTDC, no spark…………….
F. Do not want to pump fuel yet if there’s no spark



http://forums.pelicanparts.com/uploa...1109892279.jpg

http://forums.pelicanparts.com/uploa...1109892452.jpg

Even if the distributer's at the wrong angle it should spark. Have you checked the green coax wire to make sure there's a signal?

Actually any one of the holes on the distributor cap can be number one just as long as you are at TDC on the compression stroke of #1 cylinder and the rotor points at that hole on the cap. But to do it correctly I am posting a picture of where #1 normally is. So get #1 cylinder at TDC on the compression stroke and install the distributor so the rotor is pointing at #1 on the distributor cap. Make sure you have the correct firing order. Make sure you have your coil wires installed correctly and have the wires correct on the distributor. If you have the stock Bosch CDI box, you should hear some whining coming from it with the ignition on. Make sure you have the gap set on your points, when in doubt, .016" will always get you started. Have some one attempt to start the car, while the distributor cap is off. You should see the points sparking at the gap. If you have all of that done correctly you should have spark.

http://forums.pelicanparts.com/uploa...1109947464.jpg

"Have some one attempt to start the car, while the distributor cap is off. You should see the points sparking at the gap. If you have all of that done correctly you should have spark."

Well currently I'm at a loss here. First apologies for the double thread with the same title, it must have been posted twice by accident.

A. I tried the above, cap off, looked for spark at the point gap. Result, no spark at the point gap.:(

(If this makes any difference, the Permatune site says.."The Permatune system uses points only as a sensor...")

This is an original Permatune (the type Warren says are dependable), and it looks like a factory/very professional installation. Nothing was changed in the wiring (from what I see) since the rebuild.

The CD box passes bench test, and the connection wire to the distributor shows fluctuation in the points with the multimeter when cranking.

B. Tried disconnecting the ground wire on the chain housing, still no spark.

C. Re-tried spark plug test, with a widdened point gap. No spark.

D. CD Box connection shows 15.27 before cranking, and a solid 11.00 when under starter load.

So if the wire from the box to distributor has fluctuation, maybe it's the wrong intensity and not enough box output for a spark
:confused:

I don't have a spare box handy
Could it be the points? But the points are new.

That leaves only the coil that has been changed after the rebuild. So I suspect the coil. Warren says MSD High Vibration coil can be used. Does any one know the resistance values on this MSD coil?

I called a sales rep and the specs on MSD 8222 High vibration coil : 0.7 terminals 1-15, and the second I'm somewhat confused about: secondary 4.70.

The Haynes gives on my original 0.4 to 0.6 range and then 650 to 790 for terminals 1-4.

OK, if someone could interpret the results of this test:

I did Warren's (Early_S_Man's) "telegraph" spark test, with a spark plug lead and spark plug from the coil output terminal, I then with the black distributor wire repeatedly made and broke with a nearby ground, like a telegraph.

The result is that YES, a spark at the plug does occur everytime the dizzy "telegraph" wire lead is ungrounded.

How do I interpret this test? But still no spark at the plugs with normal cranking.

If the 'telegraph" test works, it means that the CD box is working. You'll notice that the spark occurs when the wire is ungrounded. Make sure that the points are fully closed when off of the high point of the dizzy cam. Rotor good? It provides the path fron the coil to the individual plugs.

Is the little black carbon bit that contacts the rotor still in the cap? It can spring out

Rotor is brand new, I don't visually see anything wrong with it.


The bit is still in the cap, and the cap is brand new.

The only thing I can think of, is that the back-up coil works, but doesn't have sufficient output to get through the distributor cap (arcing?) , so I'm going to try a MSD HV coil.

What do I do next?

I now HAVE, a "faint" spark (my interpretation) with the spark plug wire test.

I did two things:

1. Changed back to the old rotor, and

2. Narrowed the point gap so that dhoward's suggestion would happen.


How "fat" is the spark supposed to be at the spark plug? I do not want to pump fuel down the cylinders if the spark is supposed to be fat, as I'll flood the new rebuild!

Please let me know. Thank you.

The faint small sparking is gone again :mad:

You ought to get a pretty fair 'snap' when the plug fires. Blue, not yellow in color. I wish you were nearby, I like iginitions....
The pictures aren't very clear, but the stud coming out of the side of the distrubutor isn't shorting to the body of the dizzy, is it? Is that a Bosch or Marreli?

It's a Bosch. Distributor bolt (picture taken before the nut was put on), now has the nut on it.

Tried once more tonight and again no spark.

When the faint spark was there today (briefly), no snap with the spark.

Tomorrow, last chance.....I will install an MSD HV coil.

If that fails, either I'll have to try to purchase a complete MSD 6AL, or use the car just to look at. :(

(At least it isn't leaking)

OK, I've just installed the new MSD HV coil, and I am now getting spark with the spark plug test (end of spark plug wire with spark plug on it)

Since I have nothing to relate to, this is the way I can describe the spark.

1. It is a spark which travels between the top of the electrode and the white tip.

2. It does not jump outside the gap and onto the engine block when I hold the wire close to the block. Is the spark suppose to jump onto the block?

3. Is the spark suppose to be so large that it jumps outside the gap?

4. Am I getting enough of a spark to avoid flooding the engine?


Thanks

It won't jump to the block, just the closest ground, which is the electrode. Sounds like you're good to go!