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Can't get a spark from the old girl

chicken

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I'm trying to get the BJ7 going but i can't get a spark, i have probably wired someting up wrong !!
However i have power to and from the coil and to the distributer but when i put the low tension lead from the casing to the terminal pillar i get no reading from the voltmeter, am i doing something daft or would there be an earth fault ?
Oh by the way i managed to melt the previous low tension cable so guess i did something wrong, ooops !

Any help would be good.

Bemused Rob
 
Hi Bob, If you changed the points in the dizzy you just may have inadvertently connected the low tension side of the coil to earth by improperly assembling the insulators at the points.---Fwiw--Keoke
 
Koeke

Yes i guess thats what happened, a bit of smoke came up and the lead melted a bit.
So i put a knew lead on but as i say can't get power to the points.
Any suggestions.

Rob

By dizzy you mean the coil ?
 
Dizzy= Distributor---Keoke

Go inside the Dizzy. Take your meter set it on a low ohms scale. Disconnect the low tension wire from the out side. Place a piece of paper between the points. Check from the condenser 's contact terminal [do not touch the center post] to earth if the meter reads a short. Either the condenser failed or the points have been assembled incorrectly at that center post.
 
Keoke

The odd thing is i had the dizzy reconditioned so therefore i asumed everything was put together right, perhaps not !
I have a draper voltmeter but not sure if it reads ohms ? any suggestions what simble to look for.
You wouldn't have a picture of how the points should be assembled would you.

Rob
 
Hi Rob, No I do not have an exploded view of the point assembly. So lets try this.
Take a jumper lead connect it to the terminal on the coil that goes to the connector on the distributor.

Connect the volt meter to earth and the other end to the opposite end of the jumper wire.

Remove the Dizzy cap and put a business card in between the points. Now turn on the ignition and just briefly touch the other end of the jumper with the meter lead attached to the dizzy connector.

If the meter reads 12 Volts the points are adjusted incorrectly.
If the meter goes to Zero Volts you have a short at either the condenser or the point assembly.-Let me know how it turns out.--Fwiw--Keoke
 
keoke, /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif still not sure about the fire extinguisher? /bcforum/images/%%GRAEMLIN_URL%%/grin.gif
 
chicken, just wondering if you have a wiring diagram? if not i believe gregw. has posted one that you may be able to find in our "archives"
 
anthony7777 said:
keoke, /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif

still not sure about the fire extinguisher? /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

Don't need it yet wait till I get a spark---Keoke-- /bcforum/images/%%GRAEMLIN_URL%%/lol.gif
 
Keoke said:
anthony7777 said:
keoke, /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif

still not sure about the fire extinguisher? /bcforum/images/%%GRAEMLIN_URL%%/grin.gif

Don't need it yet wait till I get a spark---Keoke-- /bcforum/images/%%GRAEMLIN_URL%%/laugh.gif
keoke, thats exactly what mrs. leary said to her cow in a chicago barn in 1871. /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif
 
Anthony

I have the wiring sorted up to the coil and power accross to the distributer on the low tension lead but when i connect the other end of the LT lead to the points it earths out !!

Rob
(no use for a fire extinguisher yet !!!!!)
 
OK Rob that's one of the results we were expecting.
So we have to dismantle that center post where the condenser's end connector is located.

Here is the exact order of things you should see:

1] A small nut remove it
2] A small lock washer remove it
3] A smal flat washer remove it

Question: do you now see the connectors from the condenser and from the side of the Dizzy connector ??
If you do there is the problem!!! If not continue.

4] A small plastic insulator with a small extension on it fitted inside the loop of the point spring. Remove it
5] Conectors from the condenser and the side of the Dizzy connector
6] Remove the point spring
7] A second one of those plastic insulators with the extension on it Remove it
8] a small flat brown washer Leave it there

Now lets repeat the test you just finished performing and perform it on the conector at the end of the condenser. The volt meter should jump and then show 12 Volts Not an Earth.
-----------------------Keoke

Let us know how it goes


Somthing just passed through my mind. Do you want to tell the person's who rebuit the Dizzy you have a short in there and have them sort it out??
 
chicken, just a basic question, do you know for sure if this car is pos. ground or neg. ground? /bcforum/images/%%GRAEMLIN_URL%%/savewave.gif
 
won't really matter as far as getting a spark. Besides he can always switch the primary coil terminal wires if he's concerned there. Guess the old fashioned way with a pencil would tell him really easily.
 
chicken said:
Yes i guess thats what happened, a bit of smoke came up and the lead melted a bit.
So i put a knew lead on but as i say can't get power to the points.
Any suggestions.

Rob

One suggestion Rob, Don't take your electrical bits to any shop where a relative of " Lucas, Prince of Darkness " works.
I suspect that unknown to you, a grandson or nephew of old Lucas was in there, working on your distributor. That is why when you installed it back into your car and energized, the Lucas Smoke escaped out. And of course, you will have to find a different shop that knows how to " reinstall " the Lucas smoke back in to your distibutor. Once that has been done, the distributor will start working again.
An alternative solution to reinstalling the Lucas smoke is to install a Petronix ignitor which will eliminate the need for those pesky, Lucas smoke leaking points and condenser.
Always glad to help,
Ed
/bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
RonMacPherson said:
won't really matter as far as getting a spark. Besides he can always switch the primary coil terminal wires if he's concerned there. Guess the old fashioned way with a pencil would tell him really easily.
ron, i was trying to get chicken to "pick himself up, dust himself off, and start all over again" /bcforum/images/%%GRAEMLIN_URL%%/savewave.gif
 
Then you just have to worry about the Pertronix demons striking you one day when you do not have a backup point set in your boot.

My recommendation, based on my usage of it for over 18 years(geeze, I'se getting old) is the allison(now Crane) optical trigger ignition. To me, once installed, it is foolproof. I've seen a number of people who've put in Pertronix to later have it "die" mysteriously. The only Crane/Allison failure I've ever encountered was the installer didn't leave enough slack inside the distributor on the primary wire, so it chafed when the point plate was rotated by the advance. 14 years later it wore through the pigtail and shorted the unit out. Maybe the quality control has lessened, dunno, cause Crane doesn't carry the lifetime warranty that Allison did.

jmho go with the Crane
 
Keoke

From memory, (havn't got back in the shed since the weekend) when the LT wire burnt out i just undid a nut on the top removed one washer and the LT & condenser wire terminals were there, are you saying they should be further down the terminal pillar in between the insulaters ?
Probably make sense when i have a look at it.
If that is the case the numpty that reconditioned it needs some tuition from you guys.!!!
 
chicken said:
Keoke

From memory, (havn't got back in the shed since the weekend) when the LT wire burnt out i just undid a nut on the top removed one washer and the LT & condenser wire terminals were there, are you saying they should be further down the terminal pillar in between the insulaters ?

BINGO BINGO !!--Yes they should be fitted to the extension on that first plastic insulator so they can not touch that center post or the nut washer assy at the top. However, they rest in direct electrical contact with the point contact spring." SPARK "Just around the corner now-- /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif Keoke

Probably make sense when i have a look at it.
If that is the case the numpty that reconditioned it needs some tuition from you guys.!!!

Ops!! I amost forgot on the way home pick upm the FIRE Extinguisher----------- /bcforum/images/%%GRAEMLIN_URL%%/lol.gif
 
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