Resto. of Wiper Bay & GM Vacuum Valve Comparison

[Juliet P.]

Anyone have any photos which shows what is / isn't painted, what the correct (as in NCRS correct) colors for things are in the wiper bays? IE the wipers, the mechanisms, valves etc. The manuals aren't overly detailed other than flat black paint. What about the bolts? Black oxide coated?

Is there any overspray in there at all? When things are blacked out, does that mean masked form body paint, or painted black? Should the bottom sides of the wiper door and grille be painted? How neat is that chrome edge between the paint and chrome, up against the base of the w/s supposed to be?

What is that stuff peeling and cracking on the bottom of the wiper bay? Can that be restored somehow? Is it OK to get water down in there or will that cause a problem? I'm thinking heavy soap & water & scrub down followed by a hose rinse. Also how much windshield goo should be oozed out?

Is there supposed to be a red and white dot / label on the valve hoses to align with the valve colored painted dots? I think I found a red wrapped paper on one hose, but it's mostly painted blue. There are some corresponding (?) colored paint dots on my new valve. Are those NCRS correct or should I clean them off?

I purchased the GM vacuum valve (at the base of the pass wiper arm) Part # 5638487. The plastic is slightly differently molded in the groove between the screw slots. The original has an extra plastic piece in the center, with 2 slots, whereas the current GM replacement part has one long groove. Is this something NCRS judges? Is the button thing on the top supposed to be white? My old one is again totally blue. I didn't see a line item on it in my manuals or judging sheets. Is the spring thing on the wiper actuator also flat black or black oxide coated or some other finish? EVERYTHING in there is blue on my car.

I could definately use some photos. I'll put them online if you want. I got a few pictures of the 1700 mile '72 at Glen Burnie (Thanks!), but with the cover closed and wipers tucked away, you can't tell much of the details inside the wiper bay. And I didn't look that closely at the time.

Also are these infamous "be careful of these, it's a good thing you have them so protect them" rivets the ones in the sides of the wiper door support pieces? I think I'm seeing some domed rivets (partially corroded) on the lower portions (with bushings) whereas the screw parts which attach to the cover itself are on the upper portions (with bushings)? How would one restore those rivets? Should they be black / shiney / painted or what?

..as you can probably tell I've got the covers off and the new vacuum valve about to go in. I'm trying to figure out just how much cleanup / restoration I need to do in there while it's apart. I've taken a bunch of pictures and will get them developed soon. Sheesh, I really NEED a digital camera. Thank you! ~Juliet

[Joe L.]

Re: Resto. of Wiper Bay & GM Vacuum Valve Comparis

Juliet-----

Wow! You've got a lot of questions! That's what I call "getting your money's worth" out of a post. I'll see if I can offer a little assistance and, perhaps, others will "chime in" to help keep my fingers from getting too worn out here on the keyboard.

The area under the wiper door was, in my opinion, originally a medium gloss black, just a bit "flatter" than semi-gloss. If by "overspray" you mean car color overspray, I don't recall any on my 69 when it was new. I expect that the blackout took place after painting of the body color.

I believe that the underside of the wiper door was was black; I don't know about the underside of the grille; it's probably moot since it can't be readily seen.

The exposed stainless edge of the wiper door reveal molding showed a very sharp line of "demarcation" between the paint and the exposed stainless. That's because, originally, this molding had a special yellow plastic, slit tubular protector over it. After the body color was applied, the tubular protector was removed. The two corner lower reveal moldings also had this protector. In fact, SERVICE parts came with the protector, too. That's so they could be painted without exposing the stainless bead to the paint, just like in production. I have NOS examples of the corner moldings and the w/w door reveal molding(the long one)and all have the protector on the stainless "bead".

The "peeling and cracking stuff" in the bottom of the wiper "bay" is body caulk used to seal this area. It was always "gungy" even when new. You can freely apply soap and water to this area without fear. That pretty much happens anyway when the cars are washed or driven through rain. If the area couldn't survive "the wets", we'd have been in real trouble a long time ago.

I believe that the colored "dots" on the valve are supposed to align with the colored STRIPES on the hoses. But, I've kind of forgotten this, to be honest.

More later.....

[Roberto L.]

Re: Resto. of Wiper Bay & GM Vacuum Valve Comparis

I cleaned and restored recently the wiper bay area in my 70 engine detailing task. It is helpful to dissasemble the main components there. After Wiper door, arms and grille are out you may dissasemble wiper linkage which is secured to firewall in four points.

Three of them are visible and one is hidden by wiper actuator bracket (this is the more difficult point, you have to dissasemble wiper actuator which you probably have to do). Each point has two nuts and oblong reinforcement in the engine side as you see in the TCS relay position. When dissasembling check position and any other detail as reassembling is critical to get grille and wiper door flush with fenders. There is a very good post, recently, by one of the UJs, I think that was Jack Humphrey's, regarding this critical adjustment.

Then, with care you will be able to take out the full linkage (asume you disconnected central motor shaft nut) and wiper bay will be easy to clean. Lower sealant is very messy, as JG states, I reapplied it just for the next twenty years... Wiper linkage is semiflat black, and a nightmare to clean with so many links. Cleaned hoses reaching pass. arm base and switch. Grille brackets are semiflat black, if you find blue all over it probably is due to repaints, probably not original. I found red (my car is Monza Red) all over brackets due to repaint.

I think it is a good time to clean side "holes" which goes to lower fender area where you can find many things, even a previous owner saying hi! :)

Well this is what I can add to Joe's good info. Don't have good photos this time, not enough light without flash, good luck

Roberto, NCRS #30019, RMC

[Terry M.]

Re: Resto. of Wiper Bay & GM Vacuum Valve Comparis

Juliet,

This wiper area is a place NCRS does not judge very thoroughly since, as you have noted, it is not very visible.

As Joe & Roberto mentioned the cracked messy stuff is a form of sealer used in a futile attempt to keep water out. It likely was not cracked when new and if you have some interior leakage you think might be coming from this area some renewal might be in order especially if you have the linkage and doors off. I believe the original material was called Plastisol and I would check at a body shop and see if 3M has anything like it. I know they sell a light gray flowable body caulk that is paintable. If that material is available in black it would be the cats ankle for that job. I can get you a 3M number for the gray stuff (comes in a tube somewhat larger than toothpaste tube) later today on a visit to garage.

This area was painted as part of the engine bay black out procedure. Before windshield was installed, black messy stuff was in there and windshield wiper pivoting posts (I think Chevrolet calls them transmissions) were installed & sealed with same sealant, but no vacuum stuff or wiper linkage was in there. Guy painting black out stood in engine compartment and shot underside of hood, engine side of radiator support, inner fender panels, top of firewall (I think Chevrolet calls this the dash - can't have fires in these cars, so no firewall.)and windshield wiper area, up windshield pillars (this is how the VIN plate and rivets get black). Someone else got the tops of the doors (after early 1968) and the rear deck vents. Thus the same black out paint (which has been discussed several times - check the archives, although I believe Joe posted the paint part number just a day or two ago for someone else) is used for windshield wiper area as for engine compartment.

Yes colored dots on vacuum switch match up with colored stripes on hoses. I believe the contact at the top of the valve is a different color on the current replacements than original. I would have to look to be sure, but I believe original is black and current is white. Others may chime in on that to be sure. Savvy exterior judges will look for that difference. After you are sure of the colors and that I have not mixed them up - simply refinish the part. Should not be too hard as this is generally low light area and hard to judge fine details.

Yes the little rivets on the side of the wiper door are the ones some folks fuss over. If you must change them let me know and I'll tell you where to get them, but you will have to buy thousands at a time. They are not that big a deal, just another minor PITA like hundreds of other things on these cars. Later in 1971 or 1972 they went to small Phillips head screws here, those might be even harder to replace.

Good Luck - sorry for the long post.

Terry