How to patch heat valve vacuum line?

[91coMANche]

While doing my engine swap, the vacuum line that goes from behind the firewall to the heater valve broke. What does that line do? I assume shut off hot water to the core? Well the heat works just fine at the moment. What can I do to fix that situation? Can I sleeve the line in rubber hose up to the valve? I have some hardline coming out of the firewall and some coming off the valve but there is a break in the middle.

[mvusse]

Just cap the line. Heat is controlled both by that valve, as well as a door that directs the air either through the heater core or around it. Without vacuum the valve defaults to open, and the door by itself works just fine to control the hot/cold air setting.

 

Why we needed a redundant heat select function is beyond me.

[91coMANche]

Ahh so that closes the valve in the summer I suppose. I guess I'll just wait until the summer to fix that line if I even fix it. It doesn't look replaceable unless I pull the dash or something like that because it is fed through the firewall. The line is sooo fine that I don't even think I could sleeve it with anything.

[mvusse]

Be aware that with the line broken and the temperature control set to anything other than hot, you will have a vacuum leak. Would be okay for now, but will you remember when the weather warms up?

[beaterheep]

cut the line back by the firewall, slap a dab of epoxy or jb weld on the end of the line. done

[Lemmon714]

I have used heat shrink tube to fix broken vacuum lines. You need to make sure there is enough vacuum line- about 1.5 inches on each side of the break. I used to get the heat shrink tube from the "Controls" electrician at work. Just be careful if you are using a torch.

[kyleag89]

What not just run a new 1/8" soft line? :dunno:

[91coMANche]

Will I be able to sleeve the line in 1/8" vacuum line?

[kyleag89]

I don't see why not or just run a completely new line in 1/8".

[alleydog]

You can get vacuum hose at the parts store that fits the 1/8" plastic lineI think its 7/64. I've done a loy of them over the years. You only need about an inch of the hose to splice it, or use as much as you need to get where you have to go.

[TrailReadyMJ]

I agree with using soft line to sleeve it as well. As long as the fitting is snug and doesn't leak, the vacuum will hold it together so no adhesives or clamps should be needed. I too have fixed many of those crappy, brittle lines with it over the years (exactly as alleydog described) with no problems. In fact I just did it the other day... they're just way too easy to break in the cold weather!

[91coMANche]

Thank guys...so I'll see if I can find 7/64" rubber line.