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As I was looking at the engine bay of my 77 (L48, auto trans, with A/C) yesterday, I noticed a broken hose.
I really don't know how it broke, because I never touched it, and my car has been in the garage for the last 3 weeks...
My cat may be responsible, because now and then he spends the day in the garage, and I left my hood open for one day.
I think it is related to the A/C - 'heater'? I don't know for sure, because my AIM is still on its way to Belgium (Are such hoses even specified in the AIM?).
The only thing I know about my A/C is that it already didn't work before this hose broke.
Can it do any damage, when I drive my car with that broken hose?
Can I repair it myself, or is it better to leave it because my A/C doesn't work?
This winter I will get my A/C system fixed by a workshop anyway...
That looks like the vacuum control line to turn off coolant flow thru the heater core. I'm not sure if 'no vacuum' allows flow or blocks flow, but it will not hurt at all to drive it that way.
Just connect those two hoses back together by replacing the broken plastic line. Copper tubing or more plastic line will work fine.
and I agree it’s just for your heater core shut off when you select max ac it stops the water flow to the heater core. Much of the time it doesn’t work in any case and the core still gets hot water to it.
Last edited by REELAV8R; Jun 27, 2018 at 10:33 PM.
I agree vacuum shutoff valve for 5/8" heater hose. My white plastic line went south on me years ago. I just followed the line back and just before the firewall grommet clipped and removed old cracked white line. Bought 5 or 6 feet of 1/8" id rubber vacuum hose and connected both ends. The 1/8" id hose fits nice on these old plastic lines. Someone has already done a repair to that white line, see rubber hose over white plastic line, your photo.
Last edited by bmotojoe; Jun 28, 2018 at 07:48 AM.
Broken 'A/C - heater' hose
