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  • 1965 - 1973 Classic Mustangs -General/Talk-
  • Classic Mustang Specific Tech

Cuts out when cold.

  • Thread starter Thread starter Mach1 Ian
  • Start date Start date Oct 11, 2008

Mach1 Ian

New Member
Nov 15, 2006
37
0
0
United Kingdom
Oct 11, 2008
#1
  • Oct 11, 2008
  • #1
Any ideas? 70 Mach1, auto, original 2 barrel carb and kept in a garage. On cold days it starts OK, runs on choke OK. The problem is that when i pull off the driveway and drive a few hundred yards up the road the engine dies when i slow down at the road junction and every other time i slow down. It takes about 3 miles for the problem to stop, until then i have to ride the brake and accelerator to stop it cutting out. I only get the problem when it is first driven and no matter how long it has been stood in the same day it doesn't happen again, only that once.

Thanks
Ian
 

zookeeper

Founding Member
Aug 25, 2001
3,415
63
109
Rogue River, Oregon
Oct 11, 2008
#2
  • Oct 11, 2008
  • #2
In colder weather, cars tend to run lean, causing the hesitaion and stumble you're experiencing. My guess is that your car is about right in warmer weather. The cure is perhaps slightly larger jetting, or it's a good excuse to try a 4 barrel carb!
 

Mach1 Ian

New Member
Nov 15, 2006
37
0
0
United Kingdom
Oct 11, 2008
#3
  • Oct 11, 2008
  • #3
zookeeper said:
In colder weather, cars tend to run lean, causing the hesitaion and stumble you're experiencing. My guess is that your car is about right in warmer weather. The cure is perhaps slightly larger jetting, or it's a good excuse to try a 4 barrel carb!
Click to expand...

Thanks for the reply, There isn't any hesitation or stumbling it just dies in a few seconds. If re jetting or a 4 barrel is still the answer what carb would you recommend?
Thanks
Ian
PS the brake lights are still working after the adjustment you told me to do on the switch.
 

zookeeper

Founding Member
Aug 25, 2001
3,415
63
109
Rogue River, Oregon
Oct 11, 2008
#4
  • Oct 11, 2008
  • #4
I've always liked Holley carbs, especially the model 1850, 600cfm vacuum secondary. As long as you buy a new one, they are as reliable as a stone and nearly as simple. It's entirely possible to get 20mpg with a mild small block, streetable gears and a light foot. They are also very well supported by both Holley and the aftermarket as far as tuning parts goes, although I find that generally taking it out of the box and bolting it on is usually the only setup needed.
Also glad to hear about the brakelights still working. I was lucky enough to get to put a few miles on my car this past summer, although I passed up the last show of the year here locally because I had to work around the house. My list of stuff to do got pretty backed up during the rebuild of my car this past 6 years!
 

Mach1 Ian

New Member
Nov 15, 2006
37
0
0
United Kingdom
Oct 11, 2008
#5
  • Oct 11, 2008
  • #5
zookeeper said:
I've always liked Holley carbs, especially the model 1850, 600cfm vacuum secondary. As long as you buy a new one, they are as reliable as a stone and nearly as simple. It's entirely possible to get 20mpg with a mild small block, streetable gears and a light foot. They are also very well supported by both Holley and the aftermarket as far as tuning parts goes, although I find that generally taking it out of the box and bolting it on is usually the only setup needed.
Also glad to hear about the brakelights still working. I was lucky enough to get to put a few miles on my car this past summer, although I passed up the last show of the year here locally because I had to work around the house. My list of stuff to do got pretty backed up during the rebuild of my car this past 6 years!
Click to expand...

Thanks again for the help! I try to get mine out as often as the weather permits which tends not be on a regular basis due to the great British summer
The car looks really good, especially in white, something to be proud of.
Thanks again
Ian
 

zookeeper

Founding Member
Aug 25, 2001
3,415
63
109
Rogue River, Oregon
Oct 11, 2008
#6
  • Oct 11, 2008
  • #6
Thanks for the kind words. I know what you mean about the weather. Here in Northern California everything's green and it's not by accident! Rain, rain, rain, but likely nothing to get excited about by UK standards. In fact, I can't whine too much, since it's actually sunny today, but I still didn't drive my car, aside from pulling it out of the garage to put away some carpentry tools. I've been remodeling my son's room and although I don't mind the type of work, it's not as satisfying as working on my fastback.
 
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