Having a problem with vacuum line routing. Tried to attach a pic. There are three vacuum connections on the firewall. Left-most under Yellow Arrow reduces to spaghetti hose. The runs to a plastic valve with three connections under Red Arrow. One of those connections run to heater box. The other under the Green Arrow has broken piece of spaghetti hose. I can't see any place this is supposed to connect.

Is the plastic valve supposed to be connected in a certain order or is it merely a connection point?

Where would the broken spaghetti hose likely connect?

Can I replace all this with 1/4" hose that isn't as likely to break?

 

The one you say goes to the heater box meaning it goes to a vacuum tank located on the side of the heater box.
The green arrow hose goes to the vacuum control inside the cab in the dash.

The red arrow is a vacuum check valve sending vacuum to the vent vacuum tank and the dash control.

 

Good info. So the red arrow valve isn't just a three-way connector? As a check valve, I assume it's directional so how can I tell if it's connected properly? And that elusive green arrow connect - how is that routed to inside the cab? Being so tiny, it's tough to see any opening. Don't I have a vacuum leak without that connected?

Sounds like I need to stick with spaghetti hose, regardless?

 

Still having trouble figuring out how to get the broken in at Green Arrow routed into cab. Can anybody help?

 

Not sure on a 1988 but if it is like my old 1983 it is like this:


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