Trouble shooting vacuum accessories
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From: Northern California
Trouble shooting vacuum accessories
I’ve got 2 ‘66 big cars with fairly complex vacuum accessory systems. Each car has the usual vacuum heater/AC controls in the dash, plus a vacuum trunk release, plus vacuum door looks. The TRICO company made most of these systems.
So there are several linear miles of vacuum hoses in each car. 55 years later these systems can have leaks as the rubber ages.
What’s weird is the Starfire will hold vacuum for 8-12 hours with a very, very slow leak down. Buy my convertible accessories won’t work much after 15-20 minutes.
From experience I know the hoses, particularly at the tips where they connect to connectors, actuators or other thing, can crack and leak. Especially the smaller diameter striped ones. Usually I just snip off a half inch, spray with silicone lube and reconnect. That’s worked o.k. for 35 years or so.
I also know that the actuators - whether trunk, or doors, should hold vacuum and not leak. I just got an NOS one and can confirm that, when new, they didn’t leak.
What I don’t know is if the dash heater controls should hold vacuum for a long time, or if a controlled leak is part of the design.
Just trying to come up with a sensible method for chasing down the leak(s) and wanted to understand the design better. At this point I’m going to isolate each subsystem and test with a vacuum pump to check the rate of leak down and test the end point actuators individually just to be sure. Is there a better way?
Any views, experience or suggestions?
Thanks in advance,
Chris
So there are several linear miles of vacuum hoses in each car. 55 years later these systems can have leaks as the rubber ages.
What’s weird is the Starfire will hold vacuum for 8-12 hours with a very, very slow leak down. Buy my convertible accessories won’t work much after 15-20 minutes.
From experience I know the hoses, particularly at the tips where they connect to connectors, actuators or other thing, can crack and leak. Especially the smaller diameter striped ones. Usually I just snip off a half inch, spray with silicone lube and reconnect. That’s worked o.k. for 35 years or so.
I also know that the actuators - whether trunk, or doors, should hold vacuum and not leak. I just got an NOS one and can confirm that, when new, they didn’t leak.
What I don’t know is if the dash heater controls should hold vacuum for a long time, or if a controlled leak is part of the design.
Just trying to come up with a sensible method for chasing down the leak(s) and wanted to understand the design better. At this point I’m going to isolate each subsystem and test with a vacuum pump to check the rate of leak down and test the end point actuators individually just to be sure. Is there a better way?
Any views, experience or suggestions?
Thanks in advance,
Chris
Running On Empty
Joined: Jul 2018
Posts: 26,056
From: Earth
Two things come to mind:
(1) One, does each hose have a hose clamp at the point of attachment; if not, possibly consider using; and,
(2) I have a (universal) hand-held vacuum/pressure gauge (w/ an assortment of various sized tapered connectors) I can insert anywhere (beginning, middle, end). It has a lock on it, also. When I get to the desired vacuum/pressure, you can lock it in w/ a simple click to hold-off line vacuum/pressure. You can leave this type gauge attached indefinitely and take readings as often as you like - very handy.
I'll note sometimes it's better to use pressure to find a vacuum leak in hoses.
(1) One, does each hose have a hose clamp at the point of attachment; if not, possibly consider using; and,
(2) I have a (universal) hand-held vacuum/pressure gauge (w/ an assortment of various sized tapered connectors) I can insert anywhere (beginning, middle, end). It has a lock on it, also. When I get to the desired vacuum/pressure, you can lock it in w/ a simple click to hold-off line vacuum/pressure. You can leave this type gauge attached indefinitely and take readings as often as you like - very handy.
I'll note sometimes it's better to use pressure to find a vacuum leak in hoses.
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