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broomhandle
I'm going nuts. I have spark to my points. They open and close. But I have no spark to my plugs.

I have a 1.8 with a 009 dist.

Any thoughts? It turns over but nothing.
messix
QUOTE(broomhandle @ Oct 1 2012, 09:38 PM) *

I'm going nuts. I have spark to my points. They open and close. But I have no spark to my plugs.

I have a 1.8 with a 009 dist.

Any thoughts? It turns over but nothing.

bad coil?

do you have spark at the coil wire?
broomhandle
Yeah, coil is almost new.
timothy_nd28
The points are either burnt, or your condenser is internally shorted.
ArtechnikA
QUOTE(broomhandle @ Oct 2 2012, 02:26 AM) *

Yeah, coil is almost new.

If you have spark at Terminal 4, but none to the plugs, it's either cap or rotor.
I once had the central carbon thingie fall out of the cap.
I have had rotors explode or otherwise fail.

And 'almost new' is not synonymous with 'known good.'
broomhandle
QUOTE(ArtechnikA @ Oct 2 2012, 02:56 AM) *

QUOTE(broomhandle @ Oct 2 2012, 02:26 AM) *

Yeah, coil is almost new.

If you have spark at Terminal 4, but none to the plugs, it's either cap or rotor.
I once had the central carbon thingie fall out of the cap.
I have had rotors explode or otherwise fail.

And 'almost new' is not synonymous with 'known good.'



cap and rotor were working before. and same with coil. but i have gnomes that come in the night and mess with my 914. so agreed. and new coil is from china. so anything thats new from china dose not count.

ill play around with rotor/cap and wires, and re-check my SP gaps.
bandjoey
Several threads on testing coils. I think if you put a multimeter across the +&- it should read the coil resistance. I. E. 3ohms. &. + to center is about 10,500. (Correct me here guys). Seems like if its over 12k it's a bad coil

Search will bring up the right values.
bandjoey
Here u go on coil
Hopefully that will resolve your idle problem. It worked for me.

~~~

Step 8. Check the Coil.

The following is courtesy ofAircooled.Net.

First make sure you have 12V going to Terminal 15 on the coil (the positive (+) terminal.
Pull the center wire out of the distributor with a rubber-handled pair of pliers.
Hold the end of the wire about 1/4" from one of the metal clips that hold the distributor cap on.
Have your buddy turn the engine over with the key.
There should be a nice blue spark from the end of the wire you pulled out of the center of the cap to the metal clip. The spark should look sound and strong and should be easy to see, even in daylight. If you get such a spark, the coil is like new. If you get a good strong yellow spark, the coil is getting old but is still serviceable. If the spark looks thin and weak (yellow is weak, blue is strong), then the coil windings may be giving out and you will need to replace the coil.
Another test for the coil -

Remove all of the wires from the coil terminals.
Attach the positive and negative, red and black, wires of the Ohmmeter to Terminal #1 and Terminal #15 that are printed (stamped) on the coil. You should get a reading of beween 3 and 4.5 ohms, which is the resistance inside the coil. A bad coil will show a higher reading than 3-4.5 ohms - you want less resistance.
Next, place the red or black lead from the meter to the center of the coil (secondary post) and to either one of the terminals, either #1 or #15. You want 9,500-10,000 Ohms. Sometimes you'll see less but you don't want to see something like 11,000 Ohms. If you have no reading in either case, the coil is trash.
If you need to replace the coil -

See our procedure for Coil Replacement if you need more information.

Remove the old coil simply be removing the heavy wire that goes to the distributor, then the two 10mm bolts that hold the coil onto the fan housing. Install the new one by reversing the process.
The thin wire coming up from the distributor connects to Terminal #1 (-). The wire from the ignition switch connects to Terminal #15 (+), and the big center wire connects to the center of the distributor.
Try the check on the new coil to see what a good spark looks like.

A note from Bob Hoover regarding the coil (black vs blue) -

Question: Is it beneficial to use a Bosch Blue coil with it, or would stepping up the coil help out also?

Bob responded - Joke, right? :-)

Electrically, the blue coil is EXACTLY THE SAME as the black coil.

The joke here is that the amount of energy going into your coil is determined by the contact area of your points. If the coil used more energy you would need larger points.

The black coil uses varnish & tar in its construction, the blue coil uses Formavar (a high temp varnish) and polypropylene. (Cut them open. See for yourself. No mystery here. But lotsa sales hype.)

In theory, the blue coil should hold up better at higher temperatures but in fact, both coils do about the same.

(You don't really believe all the BS in the ads, do you? :-)

The only time you might need more spark than the stock coil can provide is when you have a very high compression ratio or extremely wide plug gap.

* * * * *
broomhandle
cool, ill check that. but i have starting problem. cant even get to idle. and my points are running, just no spark and the plugs. thats why im thinking its not the coil.
Katmanken
Check to see if you are getting 12v to the coil when the key is on. If that's OK then replace the condenser. A bad condenser can let the the points spark but the plugs won't.

Condensers are cheap and are included to allow the voltage to build to spark the plugs. Bad condenser, no voltage build, no plug spark.

Ohm out the coil, it may be bad. I had one recently that measured close to OK, but no spark. New coil and all was good.

Hope that helps.

bandjoey
There are not that many parts. Plugs. Wires. P&C. Coil. Google 'how to check' and you'll see lots of 914 and old VW threads to help.
underthetire
Just gotta ask, the points are hooked up the the - side of the coil, and positive on the +, tach lead on the -, and anything else?
TheCabinetmaker
Ok, you have spark from the coil wire, and the points when opened, but none at the plugs. The rotor or cap or both is trash. Use only Bosch
broomhandle
its a bosch cap/rotor, not that old. i was thinking the condesor as well.... ( how would i check that?)

and yes, hooked up.

i always know because the PO has the positive wire with a black end and the ground red... go fig.
euro911
Is your point gap set at .016" (or a dwell reading between 44 and 50 degrees?)

Are you absolutely sure the 12+ wire to the coil is connected to the positive (+) terminal on the coil, and the ['green'] wire from the points and condenser are going to the negative (-) terminal?

If connected 'reverse polarity', you can still get spark at the points and out of the coil, but it won't generate enough energy to jump the gap between the rotor and cap terminals and the spark plug gap under load.

How to check a condenser (capacitor):

1.Remove it from dizzy
2. Attach the body the to the (-) side of the battery
3. Briefly touch the wire to the (+) side of the battery (may need to use a wire jumper with alligator clips on both ends)
4. Remove it from the battery and toss it to a friend. If he jumps because he gets a jolt, it's OK laugh.gif
broomhandle
QUOTE(euro911 @ Oct 3 2012, 09:59 AM) *

Is your point gap set at .016" (or a dwell reading between 44 and 50 degrees?)

Are you absolutely sure the 12+ wire to the coil is connected to the positive (+) terminal on the coil, and the ['green'] wire from the points and condenser are going to the negative (-) terminal?

If connected 'reverse polarity', you can still get spark at the points and out of the coil, but it won't generate enough energy to jump the gap between the rotor and cap terminals and the spark plug gap under load.

How to check a condenser (capacitor):

1.Remove it from dizzy
2. Attach the body the to the (-) side of the battery
3. Briefly touch the wire to the (+) side of the battery (may need to use a wire jumper with alligator clips on both ends)
4. Remove it from the battery and toss it to a friend. If he jumps because he gets a jolt, it's OK laugh.gif



thanks that helps. im going to check the "green" wire again. green is always neg. but my father in law was saying, "on my chevy"..... so it could be moved now i think about it.

F, if thats its. im gonna be flaming mad!!!!!
rhodyguy
a 1.8 and an 009? carbs?

k
broomhandle
QUOTE(rhodyguy @ Oct 3 2012, 01:29 PM) *

a 1.8 and an 009? carbs?

k



Yes. and carb.
Dave_Darling
Let's just re-state this.

You have power to the (+) terminal of the coil. The points get grounded and then the connection opens, and they are hooked to the (-) terminal of the coil.

You've unplugged the tach wire from the coil to take it out of the equation.

The big fat wire from the coil to the center terminal of the distributor cap has spark. You've checked it with either an extra plug or just holding it close to a grounded piece of metal. The spark was fat and white and happy, not pathetic and orange.

Once the spark goes into the cap, it does not come back out of the cap. You have checked this with a known (TESTED!!) plug wire, either with a plug on the end or held close to a ground as the center coil wire above.

You have checked the resistance of the distributor rotor from the center to the tip, and it is appropriate for your setup.

If all of that is true, then either the distributor cap is effed or the rotor isn't bridging from the center electrode on the cap to the outer electrode.


So, are all of those separate things that I have listed correct? You've checked each and every single one?

If you have a fat wire, you can plug it into the underside of the cap so it bridges from the center terminal to the outer one going to your test wire/plug. Don't even hook the cap on. Then check again for spark on your test wire/plug. This will eliminate the cap itself (or that one part of it) as a suspect.

Isolate and test, methodically isolate and test. You'll find what is wrong at some point.

--DD
broomhandle
it was the bloody green wire...... I told you i have gnomes. its either my chevy father in law, or my 24/7 drunk chevy neighbor who comes over and grabs things.

sorry guys!!!!!!

but, if you makes everybody feel better, this form did fix my issue. smile.gif
Dave_Darling
Isolate and test, be methodical. smile.gif It does tend to work!

--DD
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