2F vacuum hose routing (1 Viewer)

[crackdpot]

So, I'm not super-dooper knowledgeable mechanic, but know enough to get myself into some serious trouble.

I'm replacing my worn out 2f with a used heart. The thing that probably concerns me the most is getting all the vacuum connections right...jeez!

I have service manual, and have seen the schematic showing the vacuum lines, but it leaves a lot to be desired. Might anyone know of maybe a color coded version, or something like that?....which would clarify things a bit?....not quite ready to go Weber & spaghetti free....probably soon though.

Also, what are hose specs for replacement? I'd like to get a couple spools....suggestions?

Thanks!

 

[2mbb]

here is a collection of various diagrams. May not be 100% but it's a start. When I did this many years ago (with silicone tubing from Mcmaster Carr) I put on electric wire marker labels--wrapped around each end of each tube, and a corresponding one where it connects. It would help me get it all back together correctly. now more than 10 years later, many of the labels have fallen off, but it was good while it lasted! These days you can get label print that will pring the outside of shrink tubing. I have one of these printers at work, but haven't tried it on the vaccum tubing.

Ideal Wire Marker Booklet: Ideal Wire Marker Booklets (10-Pack)-44-102 - The Home Depot

 

[OSS]

The nightmare overview illustration in the emissions manual is pretty much worthless to guarantee every hose gets connected to the right spot. I don't think it would be possible for anyone (myself included) to correctly route every vacuum hose to the right spot if presented with a cruiser that had all the vacuum hoses missing. The thing that messes up the works for an easy install is the "spaghetti" metal vacuum tubing.

While each vacuum subsystem is detailed in different chapters in the emissions FSM, it would be a daunting painstaking task to try to go by those drawings alone.

The best way to replace vacuum hoses is to swap one at a time. Pull one old hose and replace it with a new one. It helps if the new hose looks a little different than the old hose so you can keep track of what you've done.

For clustered vacuum hoses jammed together, labeling each hose (A, B, C etc) and their associated metal piping or plastic nipple with the same lettering - using blue painters tape and a black sharpie works well.

 

[2mbb]

this cartoon, that should be on a sticker on the inner fender, is pretty good at de-mystifying the spaghetti hard pipe. However, you have to have some familiarity with the components of the various systems and where they are located.

It is unfortunate that there doesn't seem to be one reference source for all the vacuum tubes: The emissions manual doesn't cover the AC idle up (for one), the sticker below and the spare parts diagrams don't show one of the HIC tubes...I end up with six different pages (in the attachment in my post above) to try and show everything.

I suppose if you have a smogged new-to-you vehicle that needs trouble shooting, you would test all the emissions system. Going through the tests is a good time to also confirm the vacuum routing for those systems.

For what sizes, most of the tubing is 3mm ID. While the toyota tubing might be available (I think the longest pieces are the cheapest), most folks use aftermarket silicone tubing. Don't use non-silicone-containing compounds (ie. buna) as they won't last. I get my tubing from McMaster Carr. You will probably need 30ft or so. There is also some amount of larger tubing...I think it is 6mm ID.

Vacuum tubing replacement has been covered many times, so try a search for more details.

 

[batthewmrown]

Like what @OSS said, change the hoses one at a time. Pull it, cut one of the same length, replace. I wasn't super stoked on the MCMaster Carr silicone hose I replaced my lines with. They're a real pain to get off down the road as they are quite snug on the ports. If i had to do it over, I'd just go OEM, even though they're boring and just black. I'm in the process of wrapping up my manifold gasket, so I had to remove all the spaghetti. Best advice I can give you there is get a silver paint pen/marker. Mark each hose, mark each port with a corresponding mark. I used dots. Take a photo on your phone of each one and from there it shouldn't be too terrible.

 

[pv40]

If your motor is out and you can desmog its way easier to do it now. But if you legally can't I get it.

 

[2mbb]

I wasn't super stoked on the MCMaster Carr silicone hose I replaced my lines with. They're a real pain to get off down the road as they are quite snug on the ports.

McMaster Carr offers two different hardness. I used "soft" (Durometer 50) and it works good for me (part K504K12 for red--other colors are available). If you "pull" the middle of the tubing it will stretch and not easily come off the nipple, but if you grab the cut end and "push" it off the nipple, it comes of pretty easily. It doesn't seem to stick like the buna rubber does. I have had this same set installed for 20 years.

 

[batthewmrown]

McMaster Carr offers two different hardness. I used "soft" (Durometer 50) and it works good for me (part K504K12 for red--other colors are available). If you "pull" the middle of the tubing it will stretch and not easily come off the nipple, but if you grab the cut end and "push" it off the nipple, it comes of pretty easily. It doesn't seem to stick like the buna rubber does. I have had this same set installed for 20 years.

View attachment 2298639

Yeah, maybe I got the wrong stuff. Idk, I got it all off with no real problems or breakage, but there were definitely some butthole puckering moment pulling on those emissions ports!