Thermal Vac Switches

Replaced the two thermal vacuum port switches that manage all the smog control devices. I seem to have them back to working in harmony again now.

Unfortunately, when I charged up the A/C system I found that the compressor is leaking at the back where the hose pad connects. Probably just the o-rings but now I need to find a set that work with 134a.

More EGR Investigation

After following the troubleshooting steps in the manual, I see the two ported vacuum thermal switches are bad. The full manifold vacuum that goes into one port is getting sent all the way back up the chain to the ported vac connection on the carb, screwing up pretty much everything. I can get new ones easily, about $35 each. In the meantime, I have plugged the manifold vac hose which seems to only affect the thermac door on the aircleaner.

EGR Issue

I'm having an issue with my '76 regarding the EGR valve operation. The old valve was weak, so was letting exhaust gas pass even with no vac signal. I replaced it with a new valve and it turns out the real problem is that it is getting a vac signal even at idle, so the idle is real rough when the hose is connected. I went all the way back to the carb and it seems the ported vacuum point on the carb body has vacuum at idle too, so the various temp switches are just passing it on. Ported vacuum should be zero at idle, right? Is the Q-Jet due for a rebuild then?

Passenger side mirror finally correctly aligned and functional! I had gotten a electric unit off of an '80s Buick some time ago and replaced the manual, dealer mounted original. I had even made a space in the dash for the control and ran the wires over to the right A-piller. But that was where it sat for quite a long time. But recently I found the head was coming loose and the angle has never been right anyway, having adapted the '80s car mounting arm to the '76 door in a not so great way. Again, quite some time ago I had gotten a correct, cable-controlled '76 model mirror on eBay, figuring I'd use the correct arm when I got around to wiring up the mirror the rest of the way. So this was the weekend make it all come together. New arm nicely mated to the '80s electric head and wired up so it's working beautifully. I tapped the power and ground for it from the clock, as it was convenient and close by.

Radiator

New radiator arrived tonight and Installed it along with a new lower hose. I have not completely buttoned things up and I need to buy coolant to fill the system tomorrow. But hte major replacement is done.

Radiator Again

Over the weekend, I tried to make the small leak of coolant stop, still assuming the drips were due to a trucculent hose clamp. But after double-clamping and still no joy, I decided the best choice is to either have a pro investigate, or just bite the bullet and order a replacement radiator. I just replaced the original a year ago with a new 4-row job. But it really looks like the seam on the right tank is weeping and with hot weather on the way, there is no room for a system that won't hold pressure. So I figured what the cost would be of having a pro look at it and determined I was going to save money by just getting a new radiator, new lower hose and new clamps, plus some coolant. I can then see if it's worthwhile to have the old radiator repaired and set aside as a spare.

Coolant Overflow Tank

Helen's original tank, which was molded into the fan shroud, was leaking and was also in the way of things. My solution was to replace it with an aftermarket job, but I didn't want a cheesey plastic add-on type, so I got a cheesey tuner add-on type instead. At least it's metal and will hold up pretty well. Disadvantage, it's kinda small for this big ol' engine. We'll see how well it works. I think I have another leak somewhere else as well.