What is this canister? and What are the lines leading to it? While changing plugs I broke the top red one. I'm thinking that some kind of small rubber line will let me mate the line back together.. Ideas?

 

Vacuum Canister. Yes a tight piece of rubber vacuum line will work fine as a splice

 

It is a vacuum reservoir. And yes, a piece of rubber hose over that broken section in the line will fix it.

 

Excellent! thanks guys! ( always nice to make sure that I'm not completely short bus)

 

One thing to keep in one is that the vacuum hoses get brittle over time. Did it break with little pressure or was it a victim of a substantial blow? If it didn't take much to break it you might want to think about replacing it, as well as the other lines. Here's a great thread from the full size Broncos site Replace Plastic Vacuum Hoses with Rubber - FSB Forums. It's specific to the 305/351, but you should get the general idea and be able to apply it to the 300.

 

you I was hammering on that line pretty hard. but since I'm working the truck over to make it run better, replacing the replaceables, I might go ahead and do the vacuum lines too.
thanks for the link.