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Engine running w/ key off question

  • Thread starter Thread starter TireSmoknWindsr
  • Start date Start date Apr 6, 2004

TireSmoknWindsr

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Half past whup'n some import's ass
Apr 6, 2004
#1
  • Apr 6, 2004
  • #1
What causes a motor to still turn over and try to start back up after the ignition has been cut off for a few moments?
 

allcarfan

The Answer Man
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Apr 8, 2001
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Apr 6, 2004
#2
  • Apr 6, 2004
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I believe that this is referred to as dieseling.
 
P

paintballtommy

Member
Jan 31, 2004
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concord, ca
Apr 6, 2004
#3
  • Apr 6, 2004
  • #3
high compression ratios when the engine is warm will actually generate enough heat to ignite the fuel/air mixture.
 

dodgestang

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Dec 15, 2003
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Apr 6, 2004
#4
  • Apr 6, 2004
  • #4
TireSmoknWindsr said:
What causes a motor to still turn over and try to start back up after the ignition has been cut off for a few moments?
Click to expand...

You can try to combat it by properly tuning your timing and your carb(and/or just idle screws). Often times you will find that one is out of whack and someone dialed up the other to compensate.
 

skywalker

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Pensacola, FL
Apr 6, 2004
#5
  • Apr 6, 2004
  • #5
I think I had a similar issue not to long ago when doing my T-5 swap. Is it just turning over some more after you turn it off? That's deiseling and from my experience is usually a timing issue. Is it actually cutting off and then trying to start back up? If that's the case try and change your ignition switch, it's easy to do, takes 10 minutes.
 
6

68restoman

New Member
Jun 5, 2003
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Apr 6, 2004
#6
  • Apr 6, 2004
  • #6
On older engines this can be caused by carbon build-up in the cylinders. It raises the compression and holds heat in which will cause deiseling. Poor timing and low octane gas can also contribute to the problem. I had this problem on my 68 until I started using premium fuel.

68Restoman
 

TireSmoknWindsr

Founding Member
Sep 12, 2002
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Half past whup'n some import's ass
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#7
  • Apr 6, 2004
  • #7
It would turn over about twice then seemingly die then sputter back up a few more times after seemingly dying. Set the timing down a little on it and it seemed to help but I think its the carb mostly. Put a different one and it needs some tuning...abit lean for one...gap down on it and it just bogs and dies.
 
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