Repo RS vacuum lines

[Dave69x33]

Richard,

Interesting info on repro actuators.  I hope the new units function better.  I read in a related pot on CRG that Jerry MacNeish tested a reproduction "high torque" actuator and said it functioned very well. Not sure what a "high torque" actuator is as it will only produce "X" torque based on a "Y" vacuum signal from your motor.  Would love to know more!

All...

I stand corrected on anything I just posted and encourage feedback.  My diagrams are based on what I learned recently from taking apart some of my old original RS component parts on my 1969 Camaro RS system.  After reading countless posts on the 1968 and 1969 RS systems, and how vacuum hose should be connected, troubleshooting the system, etc.,  I had to dig into my parts to "see" and understand how they were "supposed" to work.  I hope these pics and diagrams help.

I'll post more soon on the headlight switch and how I tested and troubleshoot it.  I also borrowed the full system diagram illustration (sorry I am not sure who made it originally to give them credit) and revised it to show the proper function of the entire...again based on what I have leaned recently.

In short, I believe the original 1969 Camaro AIM covering the RS system and how to connect the GREEN and RED hoses to the vacuum relay is incorrect.  When you study the 1968 RS hose routing diagram, it is correct with the GREEN hose connected to the relay upper "R" port and RED hose connected to the lower "G" port.  This was the only way I could get my doors to function correctly.  The only other option would be to swap the GREEN and RED hose on the actuators.  But that is (4) hose to swap which may not be long enough versus (2) hose at the vacuum relay.  Either way it will function the same!
 

Dave

[rich69rs]

Steve,

Your diagrams indirectly refers to the reverse action of repo canisters that I mentioned previously when they state hook the red hose to the G port and green hose to the R port. 

I left the red hose connected to the red port and the green hose connected to the green port on the relay valve and made the swap at the canisters so it wouldn’t be visible.

I’ll check my restoration files/pictures.  I think I have some “before disassembly” pictures of where the R & G hoses were originally connected on the relay valve - but I’d be surprised if originally R went to G and G went to R.

Interesting that ‘68 AIM and ‘69 AIM show different hose connection locations at the relay valve.

For reference, my ride is an 01C Norwood ‘69 RS.

Richard

[Dave69x33]

Here are screen shots of pages from the 1968 and 1969 AIM showing the difference how to connect the hoses to the relay. Note how the '68 connects the GREEN hose on top port and RED hose on the bottom port of the relay. The '69 AIM instructs the opposite: however, the same relay #5638498 is called out for use on both the 1968 & 1969 RS in my GM Master Parts Catalogue. 

[Dave69x33]

These are view of my old the 1969 RS headlight switch and how it works.

[Dave69x33]

More pictures of the headlight switch and how it works.

[rich69rs]

- but I’d be surprised if originally R went to G and G went to R.

Well, I am surprised!

Found some disassembly reference pictures from when I disassembled the front end of the car in 2005.

First two pictures I just took today of my original relay valve that I replaced in August 2021.  You can clearly see that the relay valve is marked "R" (top port), "Y" (middle port), and "G" bottom port.

However the third picture is the "as found" condition of the hoses connected to the relay valve prior to disassembly in 2005.  (Note: the white markings I added as additional reference as to what hose went ot which port).  Lo and behold.....the green hose is connected to the top, "R" port and the red hose is connected to the bottom, "G" port.....in agreement with the '68 AIM, but not what the '69 AIM shows.

So during reassembly, for whatever reason, I did not refer back to the third picture below, but instead hooked up my new hoses as per the port markings on the relay valve and '69 AIM.  When i did this, the headlight doors operated backward, i.e. closed with headlight switch pulled out, open with it pushed in.  My fix was to swap the vacuum lines at the canisters as opposed to doing it at the relay valve.  However, it does appear that these cars came from the factory with the vacuum lines swapped at the relay valve...go figure.

For those who think GM/Chevrolet (or any OEM for that matter) is infallible..

Richard

[Dave69x33]

How I tested my the RS headlight switch.

[Dave69x33]

Richard,

That is how I currently have my hoses connected, GREEN on top and RED on bottom, otherwise my doors will not open correctly.

Here are a few pics of my original relay.  It cleaned up very nice.  It's a bummer is leaks vacuum in the lower portion and does not work well.

[Dave69x33]

I have a spare NOS actuator #5638486 that I purchased between 1996 - 1999 while restoring my car.  It has never been used. I tested it with my Mityvac.  The piston seal must be dried out and cracked and will not hold vacuum, as the linkage rod will only slightly move under vacuum. My original actuators are in about the same condition and will not hold vacuum. 

My recommendation: do NOT spend big $s on NOS actuators unless it can be proven they will still work!

It is ink stamped "3441" which I assume is a date code for the 344th day in 1971, which would be December 10, 1971.

[Dave69x33]

Here are couple more internal views of the '69 RS headlight switch. The switch on my car is a GM NOS switch Type D1542, GM #1995191.  The electrical switch carriage detail was broken in the switch and would not the move the vacuum boot slide carriage forward (lights ON) or rearward (lights OFF).  I replaced the broken piece from my old original switch and it works good now.

[Tinkerr]

Dave,

I'm now on my third relay, the first was OER brand, the second was CHQ, the third hasn't arrived. The  new relays looked identical, as you would except. The first was in a OER labeled plastic bag, the second was in generic plastic bag inside a classic headquarters box. I believe there is one manufacture and suppliers label and package them accordingly.

When I reinstall the original the system work as it should. Neither of the new units would hold a complete vacuum compared to the original.

[rich69rs]

I have a spare NOS actuator #5638486 that I purchased between 1996 - 1999 while restoring my car.  It has never been used. I tested it with my Mityvac.  The piston seal must be dried out and cracked and will not hold vacuum, as the linkage rod will only slightly move under vacuum. My original actuators are in about the same condition and will not hold vacuum. 

My recommendation: do NOT spend big $s on NOS actuators unless it can be proven they will still work!

Absolutely agree 100%.  Why would you even consider 50+ yr old unit with probable hardened seals.

The canisters are not visible when installed with the gravel shields in place - makes perfect sense to use a new, quality repo unit.

Richard

[Dave69x33]

Thanks for the input on the repro vacuum relays.  It appears it's hit-or-miss on the repro units. In principle, the vacuum relay is a simple ON or OFF vacuum switch but the functional design is critical to get the entire RS system to function correctly and "relay" full engine vacuum to the actuators.

I had the same vacuum leak issue with the repro relay that I purchased many years ago.  I cleaned up my original relay and put it back on the car, and have been manually opening the headlight doors. I occasionally drive the car at night so manually opening the doors is not a big deal.  I recently replaced all the RS hose and was hoping once again to try and get my doors to function correctly for the first time in the 27 years that I owned the car!  I guess my headlights shining thru the door slats is kind of like the newer cars with daytime LED running lights...LOL!

Here are illustrations showing the entire 1969 RS system and how it functions. As I noted earlier in this discuss thread, I would like to give credit to whoever originally made the illustration. I borrowed and edited their illustration to show how the system works based on my recent testing, and taking components apart to study how they function.

Visually, these illustrations help me understand and trouble shoot this RS system.

[Tinkerr]

I received my 3rd relay on Saturday and finished the install today. BTW the 3rd relay was also Classic Headquarters although the vendor didn't disclose that info at time of purchase. I also changed the vacuum lines to reflect the 1969 illustration(68 Car), that Dave provided, verses the routing shown in the 1968 AIM I was using. The system is now performing as it should, although the left assembly closes slower than the right. Thanks for the help and the valuable information provided for me and other members going forward.

[Dave69x33]

Tinkerr, thanks for the info. I plan to order actuators and a vacuum
relay this week.