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Hi, I’m trying to track down where exactly this heater control valve vacuum line went as it fell off onto the exhaust and has disintegrated. Pictures would be the most help as everything I’ve read on this has been fairly useless in locating where this plugs into. This is on my 79 350 Auto. Thanks in advance
Firewall grommet yellow arrow, white line is where that line would have been laying.
This is a 77 but same location.
On a A/C equipped car that line starts at the switched side of the Vacuum operated hot water shutoff switch on top of interior heater box. On NON A/C equipped cars that line starts at port #1 of the 5 port heater control vacuum switch.
I see yours is equipped with A/C...
Firewall grommet yellow arrow, white line is where that line would have been laying.
This is a 77 but same location.
On a A/C equipped car that line starts at the switched side of the Vacuum operated hot water shutoff switch on top of interior heater box. On NON A/C equipped cars that line starts at port #1 of the 5 port heater control vacuum switch.
I see yours is equipped with A/C...
yes it is an a/c car
I found the grommet and the white line that is snapped off with hardly any meet coming out of it. Going to be a fun time fixing that.
You admittedly lost me on the second paragraph. Also from what I rememver that line had a t in it. Do you know where the other line went to? I read its somewhere on the carb but I can’t find any remnants of a line or an open port
If the stub of white poly line at grommet is long enough, a 1/8" I.D. vacuum hose will fit sung around the poly.
Just get a length of new rubber vacuum hose long enough to heater hose valve.
Thanks for the diagrams! I guess a previous owner must’ve gotten in here and added that t for some reason as there definitely was one before. Not sure why but oh well. Doesn’t seem like either side is pulling or pushing any vacuum for some reason so I guess this’ll be a problem for another day.
adding a new line to the 1/8th inch of white line that’s sticking out is going to be fun lol. Anyone got any tips for fishing more of it out of the firewall without breaking it off?
There should be a little slack on the white stripe line behind the dash. I’d try grabbing the stump with some needle nose pliers and gently tugging on it to see if you can pull a little more into the engine compartment to work with. Once you have an inch or so you should be able to jam a splice connector in there.
The alternative is to try taking off the passenger lower dash panel and seeing if you can push some slack out from the inside, but I really don’t recall if it’s possible to reach that grommet with the ductwork in place. You may have to do more disassembly to get to it.
Mine broke off at the fire wall, too. No stub. I had to drill out the old line end in the grommet and insert a new piece of hard line to create a stub. Those lines are glued in real well at the factory, no pulling them trough.
Heater control valve vacuum line
