[DeTomaso] Erratic firing

[Richard Greenblum]

I'm going to check the timing if I can keep it running long enough.  I suspect you're right about the mark jumping around.

Thanks to everyone who replied.  I'll let you know what it turns out to be...

Sent from my iPhone

> On Dec 29, 2013, at 22:20, Pantdino <pantdino at aol.com> wrote:
> 
>  
> Assuming you're using a timing light triggered by the spark to #1 cylinder and looking  at your crank timing marks, if the ignition box is sending that signal at random times you will see the timing mark jumping all over the place. 
>  
> I guess if you see the mark at a stable retarded position you could conclude the timing is retarded, but whether that would be due to the box malfunctioning or some other cause would still be unclear.  But I suppose  if the box has failed the "all over the place" condition is most likely.
> (Plug firing while intake valve is still open -> backfire thru carb, etc.)
>  
> But then I could be totally wrong.  :-)
>  
> Jim Oddie
> -----Original Message-----
> From: Richard Greenblum <pantera at austin.rr.com>
> Cc: detomaso <detomaso at poca.com>
> Sent: Sun, Dec 29, 2013 1:27 pm
> Subject: Re: [DeTomaso] Erratic firing
> 
> The timing chain is a double roller high quality steel unit, and the distributor 
> (and entire ignition system) came from Dennis at PPC in CO (I'm pretty sure he 
> takes care of the pin issues when he provides the setup).
> 
> You're right though, I should check the timing before yanking the box off.
> 
> Thanks Sean.
> 
> Sent from my iPhone
> 
> > On Dec 29, 2013, at 14:51, Sean Korb <spkorb at gmail.com> wrote:
> > 
> > Um... shears.  The distributor pin shears.  Geeze.  Spell check just
> > isn't helpful.
> > 
> >> On Sun, Dec 29, 2013 at 3:50 PM, Sean Korb <spkorb at gmail.com> wrote:
> >> Sounds like the timing is retarded.  Check the timing and see if it is
> >> stable.  Sometimes if the distributor pin stears or timing set wears
> >> it can get retarded fairly dramatically.
> >> 
> >> sean
> >> 
> >> On Sun, Dec 29, 2013 at 3:21 PM, Richard Greenblum
> >> <pantera at austin.rr.com> wrote:
> >>> All,
> >>> 
> >>> Rebuilt the Holley because it bucked when under load, otherwise ran great.  
> Before putting it back on, welded up the door panel holes in the right door 
> because they were stupidly enlarged by the shop that painted the car.  Put the 
> carb back on and it wouldn't run for longer than a few seconds before losing RPM 
> and misfiring and back firing, then dying.  Assumed it was a bad rebuild.  Put a 
> brand new carb on, same symptoms.
> >>> 
> >>> It also seemed to gain temp from cold very quickly.  I turned on the fans 
> (they're manually switched).  The engine immediately backfired twice, so I 
> turned off the fans and killed the motor.
> >>> 
> >>> In between the flat, misfiring, and rough running, it ran smoothly.
> >>> 
> >>> I forgot to disconnect the battery before welding on the door, then figured 
> (hoped) the few spot welds wouldn't do what Jack has warned us about.  The box 
> is a Mallory HyFire, and it's been on the car for a long time.
> >>> 
> >>> Suggestions welcomed.
> >>> 
> >>> I thought I was going to finally get the car back on the road...
> >>> 
> >>> Richard
> >>> Austin, TX
> >>> 
> >>> Sent from my iPhone
> >>> 
> >>>> On Dec 29, 2013, at 11:26, "Stephen Nelson" <steve at snclocks.com> wrote:
> >>>> 
> >>>> Did some of the Panteras come with 2 bolt mains?
> >>>> 
> >>>> Stephen Nelson
> >>>> 
> >>>> 
> >>>> 
> >>>> _______________________________________________
> >>>> 
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> >> 
> >> 
> >> 
> >> --
> >> Sean Korb spkorb at spkorb.org http://www.spkorb.org
> >> '65,'68 Mustangs,'68 Cougar,'78 R100/7,'60 Metro,'59 A35,'71 Pantera #1382
> >> "The more you drive, the less intelligent you get" --Miller
> >> "Computers are useless.  They can only give you answers." -P. Picasso
> > 
> > 
> > 
> > -- 
> > Sean Korb spkorb at spkorb.org http://www.spkorb.org
> > '65,'68 Mustangs,'68 Cougar,'78 R100/7,'60 Metro,'59 A35,'71 Pantera #1382
> > "The more you drive, the less intelligent you get" --Miller
> > "Computers are useless.  They can only give you answers." -P. Picasso
> 
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