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Spark Problem

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kodanja

kodanja

Obi Wan
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I cant figure it out
my 71 TR6 started fine the other day now i turn the key and it wont start. I tried pulling a plug and i dont see any spark when i turn it over, but then I get one spark when I turn the key to the off position....?/
I changed the coil, I checked the wires & i checked all the grounds /ubbthreads/images/graemlins/nonod.gif
any thoughts /ubbthreads/images/graemlins/nopity.gif
 
Dumb question, but how is your battery's charge level. Seems you are running a stock alternator and lots of amps in your stereo. Have you considered upgrading to a Delco-style alternator? Is your ignition stock or are you running electronic. Electronic ignition "brains" will burn out after about 3 minutes with the key on and no engine running. If no to the above, a short somewhere in the ignition bundle. Good time to get a test light out and start looking for unwanted current.


Bill
 
The 3 minute warning TR6Bill mentioned above applies primarily to the Pertronix conversions. I've never heard it mentioned for the Crane/Alison ignitions so it may not apply to them.

If the car is turning over on the starter but not catching, I wouldn't start your search at the alternator as the battery must have a reasonable charge. Take a read over my PDF:
https://home.mindspring.com/~purlawson/files/LucasPointsIgnitions.pdf
and see if it helps you troubleshoot the spark.
 
I spoke with John from Quantum Mech. he seems to think it may be a bad Ignition Switch.....

/ubbthreads/images/graemlins/crazyeyes.gif /ubbthreads/images/graemlins/crazyeyes.gif /ubbthreads/images/graemlins/crazyeyes.gif /ubbthreads/images/graemlins/crazyeyes.gif /ubbthreads/images/graemlins/crazyeyes.gif /ubbthreads/images/graemlins/crazyeyes.gif
I'll hot wire it later and find out


/ubbthreads/images/graemlins/england.gif
 
No knowing if you have points or not it is hard for me to tell but I offer this. With points the spark happens when the points open, that is when the current stops flowing through the primary of the coil and the megnetic field colapses (sp?). So if you are getting a spak when you turn the key off and at no other time, it seems to me that your coil primary is being fed a continuos current instead of an iterupted one. So I would look at what ever is suppose to be makeing and breaking the primary current in the coil (either the points are shorted out some how or the electronic module has latched components in it and has failed). My two cents from where I sit and with what I have.
 
I apologize for not giving the info about the points or "lack there of". Yes in fact there is a Crane electronic ignition system installed in the car, but I was not the owner at the time it had been installed,

looks like it may be time to replace that system.
 
Gello Kodanja,

the interesting point is the one where you get the spark on shut off. Check the starter solenoid connections, I think it is a white/orange cable that connects full battery voltage to the coil only when the starter is being cranked. This cable goes from the starter solenoid to the + terminal on the coil, as does the ballast resistor feed from the ignition switch, i.e there are two cables on that terminal.

Alec

PS, missed the bit about the Crane, so I would expect that the ballast resitor setup has been by passed.
 
[ QUOTE ]
The 3 minute warning TR6Bill mentioned above applies primarily to the Pertronix conversions. I've never heard it mentioned for the Crane/Alison ignitions so it may not apply to them.



[/ QUOTE ]

I burned out three (countem, 3) Crane setups.


Bill
 
Lots to think about while i'm here at work
thanx everyone for there input,

when I get home later i'll have my work cut out for me....


I'll let ya know how it works out
thanx again!
 
Success!

TIME, PATIENCE, MONEY & BLOOD!
after taking the voltmeter to every connection that Could find, It turns out to be something very simple.

There is a 3 wire connection plug between the distributor and the crane unit, one of the wires had disconnected inside the aluminum connection (not visible to the eye). So when I corrected the connection the car started right up.

It's always the little things you overlook. /ubbthreads/images/graemlins/crazyeyes.gif

Seems like I always think its the larger compontents gone bad.

Thanx everyone for your input! /ubbthreads/images/graemlins/england.gif

Well onto the next adventure!
 
[ QUOTE ]
and the crane unit


[/ QUOTE ]

You called it "the crane unit" so I will assume that that is the brand that you bought. (Used to be called Crane-Allison)If it is the standard Crane unit (I believe the number would be like 700, or something) then you do have just a few minutes with the ignition on and the engine not running before the unit becomes toast. The Crane 3000 unit (I think this is the number) has electronics built into it to avoid this screw-up. Vicky Brit are the only vendor that sells this unit, to my knowledge.

I am a slow learner but after a phone call to Crane, they finally admitted that this is a shortcoming. And then, only after much prodding.

Bill
 
yes in fact it is the crane-allison unit.

I purchased the XR3000 unit but it has not arrived yet
 
[ QUOTE ]
Success!
one of the wires had disconnected inside the aluminum connection (not visible to the eye).

[/ QUOTE ]

Congrats on the find!
That little problem (wire disconnect from connector) has stumped me in two different cars and it was recently reported by others-- easy to miss or not search for (and lots of wires) but in our 40 year old cars probably happens fairly often.
 
Congrats! It's always good to put problems behind you whether they were small ones or major ones.

Based on TR6Bill's experiences it sounds like you'll be OK with the existing Crane unit if you don't leave it on too long. I'll add that you need to be careful around water also. I ruined the one on my GT6 by getting it soaked during a hose down of the engine bay. Whether you install that new Crane unit or not... I assume a water-warning should still apply.
 
I have the unit mounted on the wheel well right now but I'll take your advise and silicone the openings around the wires as well

thanx
 
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