Captain Obvious

I don't think any of that is at my end. I think all the printer settings should be at your side. I'm no tech guru, but I'm pretty sure I can't do anything about that?

Thanks again for the help guys. I added the speaker wires and here's the latest. I've been trying to stay very close to the original diagram style and wording, but I agree with the use of the designation "cooler". I changed it to "blower motor". I have no outstanding known issues at this point. If anyone turns up a problem somewhere, let me know. Lower resolution thumbnail pic good enough to get the idea, but if you want a higher quality version, download the pdf. <V5.0> removed in favor of newer version below later in the thread

Got it, and you're right. I glommed onto this thread because it was talking about the seals, but the original intent was the later style. I'm the one who's guilty of the time shift into the older O-ring style.

I think those are for after they went away from the grooved valve cover and moved the seal to the cap.

Thanks for the help. Strange that the OEM wiring diagrams include the radio, but don't include the speaker. And I will most certainly add a speaker icon. Still not sure how to connect it, but I'll add one! So here's a couple pics of an early radio, but not the earliest. It's the one with the horizontal antenna switch, not the vertical one: I'm assuming the blue wire is 12V power in (because of the fuse and the noise filter choke ). Then that would make the other two the speaker connections: And here on the chassis side, I've got this connector: This connector seems to have basically the same colors as the one that goes to the radio. Blue power, plus the W and W/B for the speaker: But the connector shape and is different than what you posted above? And your's has four wires, while what I have here only has three? I guess I need to see where that W and W/B go.

Oops. Probably my mistake. I knew it was just the "early" valve covers, and I assumed that "early" meant "2400". I may have been a little to confining with that.

Here's the latest version of this diagram. I made it more clear what was on each side of the firewall bulkhead, and also changed the oil pressure sender wire color from Y/W to Y/B. <V4.0> removed in favor of newer version below later in the thread

The grooved valve covers designed for an O-ring were only the early valve covers "2400" style. The later style design had the seal as part of the cap like your car.

I figured that somebody went through that. I sent you PM. Thanks for the help!

So the O-ring for the early 2400 valve covers. Anyone got a source for those? Fits in this groove as pictured above: I assume it would be easy to measure the size and find a suitable replacement, but I also assume someone has already done that work so I don't have to do it again?

Here's what happens to the inside of the ignition switch after it switches the starter solenoid a bunch of times: And here's what you should do about it (note that this is for the manual trans. The auto already has a relay, but as mentioned above, they didn't wire it like this):

I've never liked the way they run the starter solenoid current directly through the ignition switch. I think they should have put a relay between the switch and the solenoid. That solenoid draws like 8-10 Amps and really chews up the contacts in the switch. Kinda stupid how on the automatic they DID put a relay in, but didn't actually use the relay to switch the starter solenoid current. They just used it as an interlock. They COULD have put the inhibitor switch on the contacts and the pull in coil on the ignition switch (instead of vice-versa). Operation would have been identical, but it would have switched the higher current load side with the relay.

Oh, and your AFR numbers look great too. And just for a data point, they are pretty much the same as my 77. Idle should be a small amount rich, cruise could be a small amount lean, and WOT should be about two points lower than the others. On my 77, mine runs a little leaner at cruise. Not sure how I managed to do that, but I'll run low 15's at light load cruise. But if I stick my foot in it, it'll snap down to 12.8 just like yours. Kinda cool to feather the gas pedal right where the WOT switch on the throttle body opens and closes and watch the AFR gauge snap back and forth between 12.8 and 14.7.

Awesome. I love it when a plan comes together. If you get energetic and want easier trimming of the gauge position, use a 200 Ohm pot instead of 2K. It would be less sensitive and easier to adjust.

And let me guess... You've never seen Aircraft paint remover either:

Those numbers look great. Here's hoping it was as simple as bad gas!! Hope it doesn't come back!!!

I looked at an early car here and the oil pressure sender uses the Y/B. So the Y/W must go to the temp sender. I'll update my diagram.

Awesome. I suspected the switch from the beginning, but was reluctant to send you there right away because of the recent replacement. Glad you got to the bottom of the issue, and hope you're good from this point forward. If you haven't already... Don't forget to remove the jumper around the starter relay and reconnect the relay. You don't want to accidentally start your car in "D"!

Yes, the click coming from the area near the passenger feet is probably the ignition relay. But it's a non-problem. The B/Y jumper across the starter relay takes all that out of the equation. in other words... With the starter relay bypassed (by shorting the B/Y wires), the ignition relay does not have any effect on the starting circuit. You should be able to completely remove the ignition relay from the car and it should still crank. So what next? I'd go upstream... Next time it acts up, I'd hotwire directly across the ignition switch and see if you can get the starter to engage. I know you said it's a new switch, but who knows. Jumper from White/Red to the Black/Yellow and the starter should spin. If it still won't crank under those conditions, I'd wiggle your fusible links around and try again. Failing that, it's time for a meter and really start digging into things.

So thinking about projects that still need attention... I still am am looking for a front spindle. Anyone got something laying around?

Yeah, there are a bunch of mistakes in the early wiring diagram. Another example is that the wire colors on your car are not the same as the diagram. The diagram indicates that both TEMP and OIL use yellow/white, but your car uses yellow/black for one of them. So a while ago I worked up (what I think is) a better version of the diagram and fixed some mistakes as well as cleaned things up a bunch. I've not uploaded my latest version, but here's the thread where we talked about it: https://www.classiczcars.com/forums/topic/69026-1970-wiring-diagram/ Which of the gauges uses the Y/B wire? Does that go to the TEMP, or the OIL? I'll change that on my diagram. And let us know how the bench testing goes.

So Zedhead posted a good pic of the starter relay earlier... it's up in the engine compartment in front of the battery. If you disconnect the starter relay and short the two black/yellow contacts together (on the car side of the harness), it will take both the starter relay and the transmission inhibitor switch completely out of the starting circuit. In other words... With the two B/Y wires shorted together, when you turn the key to START, the starter should spin even with the transmission in drive. If it still fails to crank even with that jumper in place, then it's something other than the starter relay or the transmission interlock.

The diagram (created by @wal280z , not Eurodat) says the dashed line is for Canada. And there's still no link between the seat belts and the starting of the car. They just changed how the belts and warning light and buzzer get connected.

Gotcha. You probably already mentioned that somewhere. And I hope the under load fuel pressure testing provides some clues to what's going on.

The wiring diagram says the sender units connect to a yellow/white wire (not straight yellow), but that may be on the chassis side of the gauge connector. Sometimes they changed wire colors at the connector right there at the gauge. So if it's as simple as Y on the gauge side and Y/W on the dash harness side, then yes... Your bench test connection plans should work out fine. No, you do not have to have the sender unit (either of them) hooked up. It won't cause any damage, but the needle will just rest way down at the bottom. So you can let the oil pressure connection hang open while you are messing with the temp side testing. Can you snap a couple pics of the gauge? Some of the connector leading to the gauge, and maybe something of the corresponding connector on the dash side. So we can confirm the color change there at that connector? Also, can you snap a pic of the inside of your gauge so I can see the wiring and the adjuster (if there is one). The pics I've been posting are from 280 cars. I assume the 240 stuff is the same, but I've never been inside the early 240 gauges to confirm.