Vacuum Line ID
Thread Starter
Racer
Joined: Apr 2009
Posts: 393
Likes: 0
From: Holcomb Mississippi
Vacuum Line ID
Hello All,
Trying to trace vacuum line problems and wanted to know where the line in the attached pictures goes. I think it has something to do with my heater but need expert opinions. I have attached 2 pics. In the first, it shows a T where the line comes off the line from the Vac tank. In the second, it shows where it enters the firewall below and to the passenger side of the wiper motor. Should this line come from here as I do not see it on any vacuum diagrams?
Thanks,
andy
Trying to trace vacuum line problems and wanted to know where the line in the attached pictures goes. I think it has something to do with my heater but need expert opinions. I have attached 2 pics. In the first, it shows a T where the line comes off the line from the Vac tank. In the second, it shows where it enters the firewall below and to the passenger side of the wiper motor. Should this line come from here as I do not see it on any vacuum diagrams?
Thanks,
andy
Team Owner
Joined: Sep 2006
Posts: 31,202
Likes: 4,287
From: Westminster Maryland
Hi Andy,
I believe you're on the right track. That's the vacuum supply line for the heater controls
AIM UPC1 Sheet M3 in my 71 Manual.
Regards,
Alan
JJ You beat me to it. I'm a pretty slow typer!!!
I believe you're on the right track. That's the vacuum supply line for the heater controls
AIM UPC1 Sheet M3 in my 71 Manual.
Regards,
Alan
JJ You beat me to it. I'm a pretty slow typer!!!
Burning Brakes
Joined: Mar 2006
Posts: 793
Likes: 1
From: Houston Texas
I have only found it in the AIM and it (AIM) is not specific about which line it is to "T" into. My original line, like yours, comes out of the firewall, but then mine terminates after about 3 1/2 inches. AIM says it connects to the wiper vacuum but gives no info as to which line. Other folks on the forum here want to tell you to connect to a line under the dash for heater control vacuum because other diagrams like Dr. Rebuild recommend that, but that's not correct. It might work , but my car didn't come that way from the General. I have asked this question of Mr. Wilcox two different times and have not gotten an answer yet. I'm sure my question has gotten lost in the hundreds he gets. Guess I can't be of any more help than that.
Dan
Dan
Last edited by jetjockey; Jul 12, 2009 at 11:11 PM.
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Team Owner
Joined: Sep 2006
Posts: 31,202
Likes: 4,287
From: Westminster Maryland
In 1971, the AIM shows that the T was to be put in the yellow windshield wiper vacuum hose. By 71 this vacuum supply was in a preformed metal tube that ran left to right along the fire wall behind the engine. The AIM note says to run 4" of yellow striped hose from the right end tube, then cut for the T and then have the yellow hose continue to the wiper relay valve on the inner fender panel. The 1/8" nipple of the T has the hose that runs to the heater control. The look and feel of the hose is unlike the other wiper/headlight hoses but is smooth and shiny like the heater vacuum control hoses.
The info is really tucked away in the AIM, like it's a secret. UPC 1, Sheet M 3.
I guess that because it's not part of the wiper or headlight systems it's so well hidden from the info on those systems. You really need to be looking for heater/console information to come across it.
Regards,
Alan
The info is really tucked away in the AIM, like it's a secret. UPC 1, Sheet M 3.
I guess that because it's not part of the wiper or headlight systems it's so well hidden from the info on those systems. You really need to be looking for heater/console information to come across it.
Regards,
Alan
Last edited by Alan 71; Jul 13, 2009 at 07:28 PM.
Burning Brakes
Joined: Mar 2006
Posts: 793
Likes: 1
From: Houston Texas
I gotta believe Alan is on to something. At this point after re-reading other peoples posts on my similar question several weeks ago it has to be the yellow hose going to the wiper system. However, I suppose some cars could well have come with the manifold source supplying the suction based on the ambiguity of the '69 AIM! Alan, I'm gonna look for the hidden secret in the '69 also when I get home. Thanks for the info!!
Thread Starter
Racer
Joined: Apr 2009
Posts: 393
Likes: 0
From: Holcomb Mississippi
location
I traced this hose to where it enters the firewall and found where it had been spliced back together close to where Mr. Alan mentions. I guess it did T in that area. i also noted that thsi hose is very diffferent from the other vac hoses with a very slick type feel abd very malable.
andy
andy