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ignition woes .

Healey Nut

Luke Skywalker
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Ok so Im trying to get this 64 BJ8 running , fresh engine rebuild .
#1 piston TDC #6 cylinder valves rocking ,rotor arm pointing at #1 cylinder, timing mark on crank pulley bang on . Removed the dizzy cap and did the voltage test to the LT wire points open 12volts to ground points closed 0 volts .
Got fuel tried to start she fires shots of flame out the exhaust but she just wont pick up .
So I decide Im going to try a fresh set of plugs , picked them up gapped them installed them ....now Ive go no spark ...nothing not a peep .
Ignition on 13 volts to the coil coil gets warm to the touch . HT lead direct from coil outlet to ground , crank er over no spark . tried the coil out of my running 67 , same result Aaaaaaaaaahhhhhhh .
Voltage test ignition on 13 volts to coil . LT wire on side of dizzy 0 volts point closed ..0 volts points open
Any ideas ??? Pulled all my hair out and gave up before I lost it . Heeeeeellllp
 
Maybe valve timing is off.

Not trying to be a smart ass but how is changing the valve timing going to give me a spark and if you read my whole post you will see that the valve timing is correct .
 
Not trying to be a smart ass but how is changing the valve timing going to give me a spark and if you read my whole post you will see that the valve timing is correct .
\With the Dizzy cap off, check to see if your rotor is pointing to the #1 post on your Dizzy's cap.
 
Ok...seeing that your not getting spark, and it was weak before it went out all together....The same thing happend to me
Last tune up...I had only 500 miles on a fresh tune and nothing! First a weak spark, then nothing at all. I switched out one item at a time to isolate the problem, condenser,coil, cap, rotor, points. Nothing worked until I changed everything at once... Another new cap, rotor, condenser, points and Lucas sport coil. Fired right up and running perfect 4000 miles now. Some of the tune up parts we are getting from the major sources are real Crap! My suggestion is to Change out ALL the tune up parts again, or if you have some known good old tune up parts install them and see what happens.

I know it sounds strange that after replacing one tune up component at a time I had no results...but after replacing everything all at once it solved my problem. I suspect the new Petronix coil I installed may have been the cause of damaging my new tuneup parts. I went back to a new Lucas sport coil and all is well in Healey Land!
 
\With the Dizzy cap off, check to see if your rotor is pointing to the #1 post on your Dizzy's cap.

Yes it is

Ok...seeing that your not getting spark, and it was weak before it went out all together....The same thing happend to me
Last tune up...I had only 500 miles on a fresh tune and nothing! First a weak spark, then nothing at all. I switched out one item at a time to isolate the problem, condenser,coil, cap, rotor, points. Nothing worked until I changed everything at once... Another new cap, rotor, condenser, points and Lucas sport coil. Fired right up and running perfect 4000 miles now. Some of the tune up parts we are getting from the major sources are real Crap! My suggestion is to Change out ALL the tune up parts again, or if you have some known good old tune up parts install them and see what happens.

I know it sounds strange that after replacing one tune up component at a time I had no results...but after replacing everything all at once it solved my problem. I suspect the new Petronix coil I installed may have been the cause of damaging my new tuneup parts. I went back to a new Lucas sport coil and all is well in Healey Land!

Thats what makes it weird as the car was running before I stripped it . Never touched the dizzy or the carbs all the ignition components are the same ones as when I stripped it and she ran like a champ before stripdown . The only thing I have since changed is the plugs , just had a brainwave that maybe the points are grounding out somewhere ,possibly I just disturbed something with all the farting around under the dizzy cap .
 
Ok so Im trying to get this 64 BJ8 running , fresh engine rebuild .
#1 piston TDC #6 cylinder valves rocking ,rotor arm pointing at #1 cylinder, timing mark on crank pulley bang on . Removed the dizzy cap and did the voltage test to the LT wire points open 12volts to ground points closed 0 volts .
Got fuel tried to start she fires shots of flame out the exhaust but she just wont pick up .
So I decide Im going to try a fresh set of plugs , picked them up gapped them installed them ....now Ive go no spark ...nothing not a peep .
Ignition on 13 volts to the coil coil gets warm to the touch . HT lead direct from coil outlet to ground , crank er over no spark . tried the coil out of my running 67 , same result Aaaaaaaaaahhhhhhh .
Voltage test ignition on 13 volts to coil . LT wire on side of dizzy 0 volts point closed ..0 volts points open
Any ideas ??? Pulled all my hair out and gave up before I lost it . Heeeeeellllp


Easy. At this point (pun?) the points are grounded. Electrically, that's what the distributor sees. Nylon insulator block on wrong side, spring of points on wrong side of block, just about anything.
Just use an ohmmeter, disconnect primary to distributor at coil, start checking.
You just never know what has come loose, fallen, shorting to ground.
Dave
 
Simply check...just to be safe.....do the points open and close when cranking? They could simply have closed up (loose screw, worn block, you know....)
You said the points were measured open and closed before you had no spark at all, so double check.
Dave
 
Simply check...just to be safe.....do the points open and close when cranking? They could simply have closed up (loose screw, worn block, you know....)
You said the points were measured open and closed before you had no spark at all, so double check.
Dave

Yes points open and close .

Took the distributor all apart , removed the points and baseplate etc . All parts correctly placed , cleaned everything lubed the weights etc . Put it all back together ...no spark , dissconnected condenser to create arc at points on opening .....nothing no arc no spark sweet dick......I
I need a beer !!!!!!!!!!!!!
 
Yes points open and close .

Took the distributor all apart , removed the points and baseplate etc . All parts correctly placed , cleaned everything lubed the weights etc . Put it all back together ...no spark , dissconnected condenser to create arc at points on opening .....nothing no arc no spark sweet dick......I
I need a beer !!!!!!!!!!!!!
. Before you end up needing a hair transplant, try putting in All new tune up parts including a Lucas sport coil as we talked about....I have a feeling those old ones are shot!
 
Further update . Dissconnected LT wire from side of dizzy . Checked for continuity with meter between LT connector and ground . Ground is there when points are closed but not when open so thats good .
Checked all HT leads for continuity found lead between coil and dizzy bad connection in cap end ....Ureka whooo hoo merry xmas blah blah blah ...... not so fast fixed the lead checked continuity all good . put it all back together still no freakin spark !!!!!!!!!!!!!!!!!
I have given up for tonight , will try my other coil tomorrow right now its beer time .
PS .....hairs all long since gone , shaved my head to help a little guy with leukeamia years ago and never looked back .
Im not into just changing everything that doesnt prove which part is to blame and you end up tossing a whole pile of parts that you dont know the condition of .
 
Well, tomorrow is another day! Merry Christmas and all the best! I am sure you will find the little Gretch that stole Christmas soon! I am going for a beer as well..
 
Ran across similar lack of spark on my son's MGB this summer and it was the insulator inside the dizzy on the wrong side causing a ground condition. As far as firing flames out the exhaust, sounds like distributor rotor is off 180 degrees. Bob
 
If it worked before it should work again its prob a stupid thing that's the cause of no spark if no wiring was changed there should be spark I would see if the fuse was blown, it can only be a combination of the coil or the condencer
 
Update .
NEWS BULLETIN !!!!!!!!!!!!!!!!!!

IT RUNS WHOOOOO HOOOOOO:friendly_wink::emmersed::encouragement::wink-new::D
Turns out it was none of the tune up parts , Dizzy cap, leads , plugs , condenser points etc etc all ok. Valve timing bang on , ignition timing correct .

Turns out it was a faulty battery isolater switch . The main starter connection was good but the small black/white wire connection was still grounded with the isolation switch on so NO Spark . Fixed it now she runs and I can get the new timing light working and start some fine tuning and playing .
:excitement:
 
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