1985 K20 4X4 CA emissions vacuum line help!!

[Avatar]

I have a 1985 Chevy K20 4x4 3/4 ton auto trans long bed with a GM Goodwrench 350 and an Edlebrock carb. The vacuum lines were a disaster, hoses missing, no connected, etc. A drunken monkey must have done the work. I found the correct vacuum diagram from autozone's website. It is the UHX codefor the 350ci V8 4bbl federal low altitude with autotrans.

http://www.autozone.com/autozone/repairinfo/repairguide/repairGuideContent.jsp?pageId=0900c1528004c3cb&CJPID=3818435&cmpid=cj

After reconnecting, and adding the appropriate vacuum hoses, I still have a few questions.

1) I can't find the "EGR BLEED SOL" They are nearly impossible to find online for sale, or even a photo of one. Does anyone have a photo of theirs, and its location under the hood? Is it a CA smog necessary item?

2) I'm not sure where the "TRANS CONV VAC SW" and "Delay VLV" are, or what they looks like. There are three switches near the thermostat housing, two of these switches have 4 hose connections (one is the EGR/PURGE/TCC/TVS, the other is the EFE/DIST TVS). The third switch has 2 hose connections and sits on the thermostat housing, driver's half. Is this the "TRANS CONV VAC SW"? If not, where would it be, and can someone post a pic, or a link to a pic?

3) The vacuum choke device at the rear of my carb is currently connected to a vacuum line connected to the rear of the carb (manifold vacuum I believe, however no the same "MANIF VAC SOURCE" in the UHX emission hose routing diagram from autozone). This line is also shared by the EGR. Is this OK? The Edlebrock carb is not stock, however the techs at Edlebrock told me that the vacuum choke device should be connected to the manifold vacuum source.

4) Because this is a California emissions vehicle, am I correct in using the UHX emission hose routing diagram (federal low-altitude with auto trans). The other option is the "federal high-altitude with auto trans", which has a slightly different Air Cleaner vacuum line setup.

[bake74]

     First off welcome to the site.
     From a search on google for the EGR bleed solenoid for a 85 Chevy I found this pic.



     The  "TRANS CONV VAC SW" should be down by the transmission I believe.  Here is a link to one.  And a pic.



      The vacuum delay valve for a 1985 Chevy K20.  See link, that is just one place to get it, open link and see pic.

3) The vacuum choke device at the rear of my carb is currently connected to a vacuum line connected to the rear of the carb (manifold vacuum I believe, however no the same "MANIF VAC SOURCE" in the UHX emission hose routing diagram from autozone). This line is also shared by the EGR. Is this OK? The Edlebrock carb is not stock, however the techs at Edlebrock told me that the vacuum choke device should be connected to the manifold vacuum source.

      I am not sure what you are asking here, but in the diagram (from autozone), your EGR vavle is connected to the EGR bleed solenoid before it connects to anything else.

4) Because this is a California emissions vehicle, am I correct in using the UHX emission hose routing diagram (federal low-altitude with auto trans). The other option is the "federal high-altitude with auto trans", which has a slightly different Air Cleaner vacuum line setup.

     I have looked this up before on the CA. DMV website for smog.  IIRC, you have to be above a certain sea level (I forget what it is exactly) to be tested for the high altitude.  Unless you live in Truckee or by Big Bear or the like I would say the low altitude diagram is the one you want.

[bd]

Avatar, we need a little more information.  Which transmission do you have - 400 (M40), 350C (MV4), or 700R4 (MD8)?  Clarify whether the truck was built to California or 49-state emission standards.  The "UHX" label only applies to vehicles built for original sale outside of California.

For 350C and 700R4 transmissions the "TRANS CONV VAC SW" imaged above by bake74 is located on the firewall above the power brake booster...

Here is the 700's vacuum switch

Typically the "Delay VLV" is blue/black with one port in and one port out; it's generally located within a few inches of the pictured TCC vacuum switch.  The TH400 doesn't use a vacuum switch or delay valve, since it doesn't have a lock-up torque converter.