Repo RS vacuum lines

[Tinkerr]

I purchased a repo vacuum line kit for 68 RS headlights.  Does anybody know if packaged hoses are precut to exact length or are they to be trimmed as necessary? I think I could tighten some of lengths up a little. I don't have any originals to reference for length. Thanks

[169INDY]

While I don't have length data, I can offer advice: Esp at the canisters and the "T-ee's be a little generous to allow for slight trimming at later dates if the hoses are stressed and spit over time.

[Dave69x33]

About 3 weeks ago, I purchased a replacement RS hose kit from Heartbeat City Camaro out of Detroit for my '69.  I am posting this note during my lunch break at work and don't have the package who see who manufactured the hose kit at the moment. 

All told, the hoses in my kit came with extra length. I test matched them to the lengths of my older hoses to make sure they were long enough, but I made sure that there was some extra slack length before I trimmed them to the usable length. My experience has been that the hoses tend to deteriorate, split, and crack where they get pushed (stretched) over the fittings.  The extra slack allows you to trim an 1/2" - 1" off the hose the reconnect it if needed in the future.

[Charley]

Are the colors any better or can you instantly tell they are repo when the hood opens ?

[Jonesy]

I have never had much luck with repo RS hoses. They all end up splitting where they connect on to something.

I saved all my originals just in case.

[68SSL35/M40/O2]

Purchased a repo kit years ago, hooked everything up. did'nt work. searching and searching. come to find out, the "T's" where not drilled out, just plastic "T's". drilled them out and worked good.

[Tinkerr]

I'm going to install the hoses this weekend, hide a little excess under the dash and at the actuators. Thanks for the input.

[cook_dw]

Something you might try is to use a heat gun on the portion of the hose that goes over the barbs and make the rubber pliable to allow it to stretch and then cool so that it relaxes the rubber so it isn’t under tension.  Just a thought.  Of course try it on a scrap piece first to make sure the rubber will hold up from the heat.

[69Z28-RS]

Are the colors any better or can you instantly tell they are repo when the hood opens ?

Here are my original vacuum hoses laying atop the CHQ package of repro hoses I purchased in 2012 (still unopened).  Other than the 'dirty' originals, the colors look very good and close to the originals.  It appears they've only gone up $7 on their price (less than 10%) in the past 10 yrs which isn't bad in these inflationary times!
http://www.autometaldirect.com/chq-headlamp-vacuum-hose-set-color-coded-69-camaro-rally-sport-p-1882.html

[bowtie68iho]

I don't have either a 68 or 69 AIM in front of me, but I recall that on 68 RS Camaros, one of the smaller RS vacuum hoses from the headlamp switch had an orange stripe , the other one was black (uncolored).  The repro hoses for these two hoses are red and black.  The 69 AIM may show orange for this hose too, like the 68 AIM.  You'll have to check.

I guess you could use a 1/16-inch pinstripe paint roller with orange ink (flexible type ink made for rubber hoses) to color a small black ribbed vacuum hose to be correct.

[Charley]

Have a pic of a yellow stripe hose ?

[169INDY]

Yes. Orig Factory GM Hoses Scrap kept from the 1980's hose kit swap outs:
LOS/VN 68 & 69 R/S Cars.

The yellow is very aged and almost beige (ish)

Note, I cannot be sure or remember where I harvested the white hose, posted as color resolution (sp) reference for the requested "Yellow"

Jim

[Dave69x33]

In the repro RS hose kit I used and mentioned earlier in this discussion thread, the striped hose from the headlight switch had a reddish stripe rather than orange as called out in the 1969 AIM.

Good tip to verify that the plastic tees that come with the kit are clear with no plastic molding flash to block the vacuum pressure.

[169INDY]

I can post a (PIC) of the  smaller diameter preserved factory hose to the underdash switch on a LOS 69.
Red-Orange LoL,,,,

[firstgenaddict]

First photo - original orange on the left and the one I did for the L78 Pacer on the right.
Second photo on the L78 Pacer
I used a Pinstriping brush and created a little V shaped guide to pull the hose through while keeping my hand in a braced position over the guide.

[Dave69x33]

firstgenaddict,


Nice work! Many years ago I did some logo design, sign painting, and a small amount of pin striping.  Using a pin striping brush is a bit of a lost art!

Questions:
1.) What paint did you use, enamel from a hobby store (i.e. model paint)?
2.) Did you first clean the hose with alcohol or other cleaner to remove the red stipe or just paint orange over the red?
3.) Was it tricky to keep the new hose straight, and prevent it from twisting, as you pulled it thru?

The toughest task I had was removing and then installing the two vacuum hoses and grommet that go thru the fire wall to the headlight switch.  I had to remove the bolts that secure the power brake booster/master cylinder assembly to the firewall, pull and tie forward (away from the firewall) it with rope forward to gain access to the grommet hole. Prior to that, I had to disconnect the brake push rod clevis from the pedal.  I forgot how tight that space is to work in under the dash! 

I disconnected the old hoses from the switch and left them in the grommet and pushed and pulled the old grommet out of the firewall from the engine bay side. I used small zip ties along the hoses so they would not slip by each other.  I installed the new hoses in the grommet with a bit longer slack length, secured them with a few zip ties along the hoses, then pushed the grommet/hose assembly into the hole in the firewall from the engine bay side.  It took several hours to install the grommet in the firewall. I had to use a small flat blade standard screw driver to push the inside lip of the grommet thru the hole, as the grommet has lips to seal on both the outside and inside surfaces of the firewall sheet metal.   Its very tough reaching around and behind the brake booster and brake lines when the car is fully assembled. It was a much easier job installing the hoses/grommet during the restoration without the brake booster and front end sheet metal in place!

Has anyone done this RS hose replacement on a finished 1968-69 RS differently?  Is there an easier way without dismantling the front end sheet metal?

I thought about installing the grommet in the firewall then pushing/pulling the hoses thru the grommet; first applying something like liquid dish soap or Vaseline to the hose. 

Sorry for hijacking this discussion thread.  Perhaps this discussion belongs in the "Maintenance" topic category?

   
 

[Tinkerr]

I’ve found the hose installation is straight pretty forward on a assembled car. I’m going to tackle the firewall grommet as soon as my son is available for the under the dash work. I think it will be easier with people and he’s a hell of a lot more flexible.

[cook_dw]

Excellent work as always James.

[Tinkerr]

James, The techniques and tools you come up with to recreate the factory markings are nothing short of amazing.

[firstgenaddict]

I used orange one shot which I thinned way more than you would to pin stripe a panel.
It was not very difficult to keep the hose straight, however I had left the hose hanging from one end for a few days so it had no curl in it from the beginning.
I used a lab tower with clamps to hold the guide at head height and then without lifting the brush pulled as far as I could then, re-gripped without lifting and pulled the last 2 feet, there is IIRC a slight, 10%? fattening of the line at that point, however it is either under the dash or at the firewall grommet area and is not even noticeable when fully exposed and pointed out.

FWIW I take the hoses out a week before I am planning on doing anything with them... lay them out, organize, and then hang them on the wall or draped over something so they have a big lazy arc with the ends hanging. If they are allowed to relax and untwist from the coiling, they are much easier to get into a new position.
 
Easiest way- first the grommet and then the 2 lines through grommet-I think I used windex.

[Sauron327]

I've only been  doing this four decades. Fab work, mindless panel replacement, restoration, pinstriping and hand lettering. Not a big deal. I guess the cars on the the cover on Muscle Car Review I've done do not count. Nor does the owner who is my best friend who owns over 50 cars not including historic flop top cars. He is a real gearhead who understands mechanics and paintwork. Chuck Fisher. Last name Fisher by the way.

HOK makes a lettering and striping paint also. I've only been using that for ten years or so. I like it for certain jobs. Buy some brushes and see if you have the ability to do it.

[Tinkerr]

I have a follow up question. If you guys will indulge me. When the vacuum lines travel down the front of the core support to the canisters do they route down and around the frame horns or on top of the horns between the inner fenders? Thanks

[Dave69x33]

Tinkerr,

I am still working on my '69 RS headlight system, testing the components, and trying to get my system to work correctly. I'll post pictures how I routed my hoses to the actuators within the next few days. 

To answer your question, the RED and GREEN actuator hoses do route down and secure to the front of the core support with a plastic retainers. See item 2 #3830786 called out in the '69 AIM Z22 RPO option Section B6. If you don't have the retainers, the base of the retainer pushes into the hole in the core support, wrap around the hoses, then the tip of the retainer pushes in to the base of the retainer.  I used small wire ties along the hose to help keep them together until the hose were secured in the retainers.  I left the wire ties on for a few days until the hoses warmed up and conformed in position as everything is a bit stiff - here in Indiana it's still cold in my garage!  The hoses then route between top of the frame extensions and bottom side of the inner fenders.

BTW...I took apart a repo vacuum relay and an old headlight switch to see exactly how these components work to control the vacuum signal. I will post pictures of these components in the next few days.  All told, I believe the 1969 AIM covering the how the RED and GREEN hose connected to the vacuum relay is incorrect.  When I reversed the hose to place the GREEN hose on the top "R" and place the RED hose on the bottom "G" port, my headlight system "attempts" to function correctly. I need new actuators as my original units leak too much vacuum to fully open and close the headlight doors.  I also found that the "over center" springs that help hold the headlight doors open and closed are very stiff. If an actuator will not hold strong vacuum (old leaky seals), the vacuum force cannot overcome the spring and the door may only start to open, or only partially close.  I believe this is the situation with my actuators. If I pull a door 3/4 of the way open or closed, it will finish its travel.

If you review the RS hose routing in the 1968 AIM, the GREEN hose connects to the top port and RED hose connects to the bottom port on the vacuum relay. The GM parts books call out vacuum relay GM#5638498 for 1968-69  All, Sup #5638272.  The superseded part number 5638272 may have had the R and G ports opposite those on the newer 5638489 relay.  After bisecting my vacuum relay and studying how it works, the GREEN and RED hose must be connected as instructed in the '68 AIM: GREEN on the top port and RED on in the bottom port.
   

[Tinkerr]

The hoses then route between top of the frame extensions and bottom side of the inner fenders.

That's what I needed to know. I couldn't discern that from the assembly manual. I've been having a issue with the relays. I have a original vacuum relay that functions well, but really looks like HELL. I purchased a OER relay that doesn't work. I have another relay on the way, will see if that works. The relay ports are labeled R on the top port and G on the lower port which coincides with the assembly manual and information sheet included with the repo hoses.
Thanks for the reply. Paul

[Dave69x33]

Tinker,

Who did you purchase your newest vacuum relay from and do you know the brand?  I need to replace my original vacuum relay as it will not "relay"more than about 2" of vacuum to the actuators. I would like to know if your new vacuum relay works well.

Testing A Vacuum Relay: 

With my engine at idle producing 9" - 10" of vacuum, I used a vacuum gage and found that only about a 2" vacuum signal was being supplied to the actuators from the relay.  I verified that I had a full engine vacuum signal to the relay via the back hose from the check valve to the T-fitting that connects to the YELLOW hose that is spit between the reserve tank and the Y-port on the relay.  I was glad to see that my vacuum reserve tank will hold the 9" -10" vacuum without any leak down.  At that point I tested the R-port and G-port on the relay to confirm that the relay is functionally bad.  I expected to see full engine vacuum through the relay to the actuators.

I recently cleaned 50+ years of debris that got sucked up and stuck to the control valve. After using foam engine cleaner and warm water to flush the debris, I used a digital bore scope and tooth picks down the R, Y, and G ports to clean around the valve and walls. Tried my best to salvage the relay; the diaphragm in the relay still works and will hold vacuum (tested with a Mityvac gun). The relay responds quickly to the vacuum signal via the ORANGE hose from the headlight switch. My vacuum relay still looks very good but unfortunately vacuum is leaking past the seal diameters that control the direction of the vacuum signal between the R and G ports.

I have an older repro vacuum relay that did not work well. I took it apart to better understand how it works.  I'll post some pictures with an explanation how it works that others may find helpful. I also took an old RS headlight switch apart to clearly understand how it works.  My headlight switch would not transfer the vacuum signal to the relay and now I now understand why.

[rich69rs]

Who did you purchase your newest vacuum relay from and do you know the brand?  I need to replace my original vacuum relay as it will not "relay"more than about 2" of vacuum to the actuators. I would like to know if your new vacuum relay works well.

I had to replace my original relay last Aug.  I purchased an OER reproduction relay from Classic Industries and it works very well.  Both doors open and close together, quickly, with no hesitation or intermittent movement or hesitation.

Richard

[Dave69x33]

Thanks Richard.  I'll purchase the same OER relay.

I also need to replace both actuators as neither one functions well.  Like my relay, the actuators are the 50+ year old originals.  The piston seals must be hard, cracked, and leak vacuum. I tested their function with my Mityvac. The piston rod will move about an inch or less then stops. I spraying Boeshield T-9 in them to lubricate and try to get the piston seals to work but that did not help.

All,

Here are a few pictures of the internal components in a typical 1968-69 on the vacuum relay that show how they work.

[Dave69x33]

A couple more views of the vacuum relay internals.

[rich69rs]

I also need to replace both actuators as neither one functions well.  Like my relay, the actuators are the 50+ year old originals.  The piston seals must be hard, cracked, and leak vacuum. I tested their function with my Mityvac. The piston rod will move about an inch or less then stops. I spraying Boeshield T-9 in them to lubricate and try to get the piston seals to work but that did not help.

In 2005, after I had completely disassembled/rebuilt the front end of the car, sub-frame, engine, trans, etc., and was then in the process of re-assembly, one of the decisions I made then was to replace the vacuum canisters.  My originals were still working and I wasn't aware of any issues at the time, but my reasoning was that they were 36 yrs old at the time and that it was only a matter of time before I would have an issue and there was no better time than now to replace them. 

I had a couple of issues with the repros. 

1.  Mounting to the existing bracket was an issue requiring a minor bracket adjustment to accommodate the new canisters. 

2.  Connecting the vacuum hoses to the canisters as per the originals resulted in the canisters (and hence the headlight doors) operating backwards, i.e. headlight switch pushed in, doors would be open.  Pull headlight swithc out, lights would be on, doors would be closed.  This was aggravating but an easy fix - I simply swapped hose connections on the canisters and everything worked fine.  Canisters and hoses are covered by the gravel shields and aren't visible - so the hoses being swapped from original is not visible unless you drop the gravel shields.

That was 17 years ago and I have no idea as to whether or not this is still a potential issue.  A lot has probably been fixed, improved since then.  Just mentioning it FYI.  As an aside, the repro canisters still work fine - I haven't had any issues with them once I installed them with the mods mentioned above.

Thanks for the pictures of the disassembled relay valve.  I still have my original one and plan to dissect it as well - just haven't gotten  around to it yet.

Richard

[Dave69x33]

And illustrations that explain how the relay works.

[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.

[Dave69x33]

All,

Found this article on the 1968-69 Corvette headlight door opening system. The Corvette vacuum operated system is similar to the 1968-69 Camaro RS except the Corvette requires two vacuum relays! That would be a pain; I am struggling with a system that requires only one relay! The article has good tips how to test all the components in the system which are common with the Camaro.

http://www.corvette-101.com/vacuum.htm#relay

[Dave69x33]

Other than requiring two vacuum relays, the Corvette system uses a “Pull-Down Switch” which functions similar to the slider switch located on the top of the Camaro vacuum relay. Otherwise the Camaro and Corvette systems function the same.  In fact the GM headlight switch Type AC Delco D1542, GM #1995191 is listed for:
1968-77 Corvette
1968-69 Camaro RS
1968-77 Chevrolet Caprice
1968-68 Chevrolet Impala

[Dave69x33]

Tinkerr,

As I thought about the issue you are having, if this was my car I would run the car at idle, and with the headlight switch off, disconnect the green hose at the rear of each actuator (one at a time) and connect a vacuum gauge. See if you have equal vacuum in the green hoses at each actuator. It may take a few minutes for the vacuum system to build back up to whatever your normal engine vacuum produces. Reconnect the green hoses to the actuators then turn the lights on and perform the same test with the red hoses connected to the front on the actuators.

If your vacuum signal to both actuators is the same, it possible that the left actuator with the slower acting door, is leaking vacuum past the piston seal. If you have a vacuum pump, you can test the actuator opening  and closing function. This will be easier to do with the actuator off the car but removing it is not necessary. If the actuator is leaking, try capping off the other port and try to pull vacuum.

Hope you can get your RS system working. Would like to know what you find out if you
perform this test.   I am few weeks behind you doing the same work!

[Dave69x33]

One last thought - someone else earlier in this discussion suggest to inspect the T-fitting that split the red and green hose feeds from the relay to the actuators,  to verify there is no plastic mold flashing partially blocking the vacuum flow. I found a small about in my T-fitting and used a drill bit by hand to ream the IDs clean.

[firstgenaddict]

If you can get a hold of a vacuum pump put it in another room or outside the garage with a long hose running to your port off the engine. That way you can trace things without the engine running.

[Dave69x33]

All,

To follow up on the vacuum relay testing I performed, I wanted to share some picture of my original relay and the build up of debris that can get sucked up into the unit during years of use.  I used a digital microscope connected to my laptop to get the images.  The pictures show views thru the R, Y, and G vacuum ports before and after cleaning.  I blocked off the small vacuum hose connection at the slider switch on the top of the relay then sprayed foaming engine degreaser into the three vacuum ports, and into into the bottom of the relay. Any mild cleaner such as Simple Green will work. I let the cleaner soak for a few minutes then rinsed the relay with warm tap water. A considerable amount of dirt and debris flushed out of the unit.  I repeated the cleaning 2 - 3 times.  In between the cleaning cycles I used the microscope and tooth pics (both sharp and blunt ends) to wipe away the clusters of debris soften with the cleaner, kind of like arthroscopic surgery! I finished by used very low pressure compressed air to help flush out the water.

As I mentioned and showed earlier in this discussion topic, my original relay will no longer transfer a strong vacuum signal to the actuators. I assume after 50+ years of usage and wear, vacuum leaks past the control valve seal diameters.  This is unfortunate as the vacuum relay still looks very good with a little restoration touches.  NOS vacuum relays are very hard to find and they cost $450.00+!

[Dave69x33]

Pics of the middle Y port. This is the port that transfers vacuum between the upper R and lower G vacuum ports.  If clogged with debris, the RS system will respond slowly, or not at all.

[Dave69x33]

After watching a YouTube video of a person who restored a set of Corvette vacuum relays, he replaced the filter that is installed in the lower window frame of the relay.  The Camaro relays include the same window frame for a filter.  I am not sure why the Camaro vacuum relay did not receive the same filter.  I decided to add soft foam filter material in my relay.  I cut the foam to size from a large piece of foam I had on hand.

While the Camaro relays are mounted higher up in the engine bay compared to where the Corvette units are mounted, there is still a fair amount of air borne dirt and debris that gets wiped up under the hood (hence the reason for a good quality air filter to the engine).  The relay is under a constant state of vacuum so debris getting suck up into unit is always a risk.  The filter material is not very noticeable in the relay when mounted in place.

Caution: The filter material must be soft and pliable so that it does not limit the tip of the valve from fully traveling downward in the relay. 

[Tinkerr]

I wanted to give a update on the issue I was having with the headlight doors. I was using the engine for my vacuum supply(open headers). After plumbing a vacuum pump to the tank I could hear a leak at the T fitting on the green line going to the left door. Once I eliminated the leak both doors operate evenly. Hope this helps somebody.

[David K]

My restoration was done in 1994. They still look great.