Observations on heater Vacuum Lines
Thread Starter
Racer
Joined: Jan 2001
Posts: 495
Likes: 0
From: ma
Observations on heater Vacuum Lines
Currently I"m replacing the vacuum lines to the heater doors,some would work some would"nt .Guess what, in cutting these hoses off,I found what looks like black rocks {read carbon}in the hoses.This explaines alot.Oh yes the vacuum filter was really bad,when I replaced it.This might be the cause of low air flow at the outlets and the hot feet that many of us suffer from because of a lack of air .This might be something to keep in mind when trying to trouble shoot this system :blueangel:
Thread Starter
Racer
Joined: Jan 2001
Posts: 495
Likes: 0
From: ma
Re: Observations on heater Vacuum Lines (virtue4u)
Just finished pulling every duct out of the car{its on my table },what I found besides the bad hoses that some were not even connected,a door that Bubba must have put in and jamed, shut and duct work that had crud that I could not belive, in the ducts{27 years worth}The only thing that made me happy was that all the diaframs are in good working order.Also one of the doors has a plastic clip that connects to the door to open and close it that was broken,{luckly the previouse owner gave me a spare heater+ air box} I looked it up with zip CC etc... no one even carries it. tommarow it all will go back together,Knock on wood :cheers:
Melting Slicks
Joined: Apr 2000
Posts: 3,286
Likes: 8
From: San Jose California
Re: Observations on heater Vacuum Lines (rdrman)
As it would happen, I am now doing much of the same thing in order to re-install my interior. Does anyone have a schematic of where all the hoses go. I don't want to waste time with a trial by error. Also, I have tested the diaphragms with a vacuum tester and they seem to be pretty good, but one does bleed down a little.
The metal valves with the hose fittings that rotate with the knurled discs that control the heater settings are not a perfect vacuum seal. How much is too much? Replacement vacuum lines, because of the very custom fitting to the metal valves, are going to impossible to duplicate without finding reproduction ones. I don't think anyone is making them. Mine are in pretty good shape, still feel quite pliable. Is there anything that they can be coated with to preserve or perhaps soften the rubber?
How much bleed down from lines, diaphragms, and valves is ok before it causes rough idle problems?
Chuck
The metal valves with the hose fittings that rotate with the knurled discs that control the heater settings are not a perfect vacuum seal. How much is too much? Replacement vacuum lines, because of the very custom fitting to the metal valves, are going to impossible to duplicate without finding reproduction ones. I don't think anyone is making them. Mine are in pretty good shape, still feel quite pliable. Is there anything that they can be coated with to preserve or perhaps soften the rubber?
How much bleed down from lines, diaphragms, and valves is ok before it causes rough idle problems?
Chuck
Team Owner
Joined: Jun 2000
Posts: 38,923
Likes: 1,481
From: Southbound
Cruise-In II Veteran
Re: Observations on heater Vacuum Lines (rdrman)
Chuck -- Assembly manuals usually have good schematics for AC/heater vacuum hose routing and attachment points. They also contain directions for the system testing done on the assembly line.
Burning Brakes
Joined: Dec 2000
Posts: 1,183
Likes: 2
From: Des Moines Iowa
Re: Observations on heater Vacuum Lines (Chuck Harmon)
Chuck, I'd suggest you lubricate the disc/seal area with a good synthetic grease, or at least vasoline. I have mobile one synthetic grease (big) tube, in a grease gun that I use for things like this, where I want the lubrication to stay put and last a long time. I believe some lubrication like I've described, can help seal this area and prevent what otherwise might be an area of vacuum loss. Bought the grease at Auto Zone.
Melting Slicks
Joined: Apr 2000
Posts: 3,286
Likes: 8
From: San Jose California
Re: Observations on heater Vacuum Lines (Easy Mike)
My 69 assembly manual only has detail for A/C cars which has completely different routing. No test procedures listed. The simple picture shown for the non a/c setup is not detailed enough to determine routing. It would be greatly appreciated if you could e mail me a copy of the 77 manual for the heater vacuum lines? The testing procedures would be particularly helpful. The silicon grease is a very good suggestion that I will use.
Thanks,
Chuck
harmonch@pacbell.net
Thanks,
Chuck
harmonch@pacbell.net
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