Ported Vacuum Switches
#1
Ported Vacuum Switches
ok, I went to the junkyard and got all the vacuum lines that I needed to replace the broken ones. They come off of the vacuum switches on the rear driver's side of the motor, under the EGR and EVP. One vacuum line goes to the EGR valve, and 2 lines connect to the Thermactor System. and One, I don't know where it goes, but my guess is that It has to connect to the vacuum tree to supply vacuum to the ports but I'm not sure, Can anyone tell me where this one goes, It's the thicker black vacuum line. I have no vacuum to the ports, so I was thinking that maybe the ports are bad. Also when I hooked up the vacuum lines, The Thermactor system stopped working because of the no vacuum. This is on an 87 300-6.
#2
Look around the engine compartment carefully for a sticker with the vacuum diagram - if not there see if you can find someone with a similar truck preferably 87 so you can copy the diagram down. The service manuals do not show anything except a generic diagram; also appparently 87 was a pretty rapid transition period so there may even be changes during that model year. I will look further for anything in 88 manual but not sure i can come up with anything. Good luck.
#3
#5
Thread
Thread Starter
Forum
Replies
Last Post
dtkkc
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
6
09-23-2016 04:49 PM
grandpas1974
1973 - 1979 F-100 & Larger F-Series Trucks
4
04-08-2016 11:34 AM
mpmccarthy
1968-Present E-Series Van/Cutaway/Chassis
1
03-31-2013 04:57 PM