70 L46 4 spd. Vacuum Hose Routing

[Bill L.]

I was looking at the AIM and Dr. Rebuild's Diagram. I have some questions since starting to replace the hoses.

1. My hoses have a small vacuum hose that is place between the one hose going to the vacuum can. The large hose with yellow strip that has a T in it with a very small vacuum line that has small clamps with the sharp tangs on it. The small hose appears to go in to the passenger compartment via the firewall next to the wiper door actuator. It is not shown in the AIM or Docs diagram. Is what is in the car original?

2. Docs diagram indicates a large hose with a green stripe going to the headlight valve on the passenger side to the middle position. My originals appeared to be with yellow stripe going to both valves, middle position. Maybe there was a problem a someone made a change?

3. Can someone post a picture of the hose/wiring routing along the driver's side on the fender? I think I am missing one of the clips that holds the hose and wiring in place. If I am missing a clip, how difficult is it to install one and can it be done with one person?

4. The AIM shows a clip and a metal tube over by the hood latch on the cowl. Should I have the clip and metal tube? What is the metal tube for and could it be missing and hence the very small vacuum line per question 1?

I looked in the Vette Vues book and the routing sorta looks like mine did. The picture is just not that clear.

Thanks, Bill

[Dennis D.]

Re: 70 L46 4 spd. Vacuum Hose Routing

Some of these observations my be late 70 I do not know that for sure. With that said...

The tee small hose goes to the heater control/vent on the shift console. I have a pic of it somewhere with that little clip I'll try to find and post.

I don't know why it shows the HL relay valve in the pass. side fender in the assembly manual. I believe that didn't start until 71. May explain the different neck length for the washer bottles. Mine is at the firewall drivers side. Also the metal vac tube going accross the firewall was a 71 thing as well I think. (does clean that area up nicely)

Think the clip arrangement is wrong in the assembly as well. Much "loop-ier", Thats a word right?, on the 70 than the nice straight parallel hose routing of the71.

[Bill L.]

Re: 70 L46 4 spd. Vacuum Hose Routing

Well I think that answers almost everything. I sure like the 71 routing better. Do not like loopiness

The only other questions is the two large hoses with yellow stripe versus the one yellow and one green Dr. Rebuild shows on his diagram going to the valves under the nose.


Bill

[Dennis D.]

Re: 70 L46 4 spd. Vacuum Hose Routing

It ain't pretty but this is an untouched 70 front clip. This the relay you mean?

[Terry M.]

Re: 70 L46 4 spd. Vacuum Hose Routing

The tee small hose goes to the heater control/vent on the shift console. I have a pic of it somewhere with that little clip I'll try to find and post.

I don't know why it shows the HL relay valve in the pass. side fender in the assembly manual. I believe that didn't start until 71. May explain the different neck length for the washer bottles. Mine is at the firewall drivers side. Also the metal vac tube going accross the firewall was a 71 thing as well I think. (does clean that area up nicely)

I seem to remember a discussion and picture of the small hose going to the interior in another thread recently. The five free searches at the bottom of the opening page didn't have subject matter that looked like that question, but knowing how often we stray from the original topic of the thread .... ????

[Dennis D.]

Re: 70 L46 4 spd. Vacuum Hose Routing

I seem to remember a discussion and picture of the small hose going to the interior in another thread recently. The five free searches at the bottom of the opening page didn't have subject matter that looked like that question, but knowing how often we stray from the original topic of the thread .... ????

Thanks the truth Terry. Thats why I usually print to save. Problem is the old mind's archive is down

[Dennis D.]

Re: 70 L46 4 spd. Vacuum Hose Routing

Here's the connector from the discussion....







found the clip pic. Not on the tee but I think its on that line and same type clip.

[Terry M.]

Re: 70 L46 4 spd. Vacuum Hose Routing

Ah Ha! Go find another of those. Good Luck.

[Bill L.]

Re: 70 L46 4 spd. Vacuum Hose Routing

That is the connector and those would be the valves!


Thanks.

[Terry M.]

Re: 70 L46 4 spd. Vacuum Hose Routing

Those are the headlight valvs, and they are under the nose between the headlamps on ALL 1968-1973 (and I think some years later as well) Corvettes. There was only one relay in 1968 and most of 1969, but then they added a second relay for faster headlight response.

[Bill L.]

Re: 70 L46 4 spd. Vacuum Hose Routing

I am still curious regarding the color of the hoses. The diagram I received from Dr. Rebuild indicates a hose with green stripe to the middle of the passenger side valve. The hoses for both valves were yellow striped on the hoses I removed.

Any thoughts? I might put some of the original hoses back on for correctness where they are still pliable.

Bill

[Terry M.]

Re: 70 L46 4 spd. Vacuum Hose Routing

If memory serves, there are letters (R, G, & Y) by each of the ports on the original vacuum valves. I have also seen some originals with a dot of color by the port on the valve that matched the letter -- although those with the colored dots may be for certain years.

I believe it is more important where the hose goes to than the color of the stripe. The stripe colors were an aid to the assemblers of the vacuum hose assembly, and the installers of the vacuum hose assembly into the car. I don't know of a single judge who can look at the vacuum hoses and tell you if they are connected correctly. If the hose connects the wrong parts f the system some function of the system will almost surely be lost.

Ask yourself if your job was assembling a bunch of hoses all day long, and you ran out of a hose with a green stripe -- what would you do? Especially if you were paid by the number of hose assemblies you produced.

[Bill L.]

Re: 70 L46 4 spd. Vacuum Hose Routing

HI Terry.

Thanks for the input. Makes complete sense.

Thanks everyone as always. I just keep on learning.

Bill