• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

Vacuum/Electrical Question

dprio34

Jr. Member
Joined
Feb 14, 2015
Messages
130
Loc.
Las Vegas, NV
The attached foto is of a switch/valve that is electrically connected but has no vacuum input or output. The Bronco seems to be running fine without it, but the question is, what is it, and how should/where should the vacuum connections be routed to? Or should I eliminate it completely? This is off of a 1972 302 with 2 barrel ford carb.

Any help most appreciated.
Regards, Don
 

Attachments

  • Vac1.jpg
    Vac1.jpg
    48.2 KB · Views: 58
  • Vac2.jpeg
    Vac2.jpeg
    61 KB · Views: 62

jckkys

Contributor
Bronco Guru
Joined
Mar 15, 2012
Messages
5,221
According to this diagram from the Mustang Barn sight;
http://www.mustangbarn.com/images/v...nic spark control, and air cleaner sensor.gif
The vacuum solenoid is activated by a temperature switch, (I don't know where it is or at what temp. it turns on) and the vacuum source is the ported vacuum nipple on the carburetor, that only pulls vacuum under part throttle operation. This diagram looks like the EB 302s in '72, but different delivery locations like Cal. may vary somewhat.
 

Viperwolf1

Contributor
electron whisperer
Joined
Aug 23, 2007
Messages
24,448
The attached foto is of a switch/valve that is electrically connected but has no vacuum input or output. The Bronco seems to be running fine without it, but the question is, what is it, and how should/where should the vacuum connections be routed to? Or should I eliminate it completely? This is off of a 1972 302 with 2 barrel ford carb.

Any help most appreciated.
Regards, Don

That solenoid is part of the transmission controlled spark setup found on some '72s and '73s. Here are some pics from an unmolested original '72 setup.

The ambient sensor switch is in the door post. The spark control sensor switch is in the transmission.
 

Attachments

  • TRS.gif
    TRS.gif
    9.7 KB · Views: 104
  • IMG_3604.jpg
    IMG_3604.jpg
    115 KB · Views: 74
  • IMG_3605.jpg
    IMG_3605.jpg
    126 KB · Views: 66
  • IMG_3606.jpg
    IMG_3606.jpg
    121.8 KB · Views: 65
  • IMG_3607.jpg
    IMG_3607.jpg
    123.2 KB · Views: 69
  • IMG_3608.jpg
    IMG_3608.jpg
    129.5 KB · Views: 65
  • IMG_3609.jpg
    IMG_3609.jpg
    67.4 KB · Views: 68
OP
OP
dprio34

dprio34

Jr. Member
Joined
Feb 14, 2015
Messages
130
Loc.
Las Vegas, NV
jckkys & viperwolf, Thanks for the info. I searched around and couldn't find anything. There needs to be a level higher than Guru for you guys. The PO put a column 3 speed on the floor. Again, seems to be running fine without it being properly connectled. Need to do some further investigation I guess. Thanks for putting me on the right track!
 
Top