I'm going off the gauge, just vapor comes out of the radiator cap but that's it.

As soon as I put it in drive or reverse, it immediately goes up. If I actually drive it, it'll go all the way to the right. If I put the blower on(heat or no heat), it'll go to the right.

Thank you all for the replies.

 

I was going by that description from before, and it sure sounds like a gauge rather than actual heat issue. Just putting it in gear does not make the heat instantly go up. OR at least I can't imagine how. Nor should just turning on the heater.
Normally...

Paul

 

Update: I narrowed it down to a grounding issue. Once I pinpoint it it'll probably solve most of my issues. Again, thank you all for the help.

 

where can one find a replacement spring for the lower hose? Mine doesn't have one and maybe it would help.....those 100+ degree days are not kind to my truck.

 

https://www.npdlink.com/search/produ...0000&year=1977

 

It would be easier to wind up your own from a coat hanger.

 

I replaced the battery cables and cleaned up the surface on the block for the ground, didn't fix it. I added a ground from the battery to the bay/voltage regulator and that solved all my issues. No more gauges pegging, flickering lights, radio cutting off, etc. I plan on going ahead and adding extra grounds throughout the truck.

Thank you all again for the help.

 

Hey, a great result! Thanks for the follow up to let us know.
Hopefully it's a permanent fix, but at the very least we once again see how important that final leg of the electric circuit is on our old rigs. More now than ever, given the age of these things now.

Double check the one from the back of the engine to the cab firewall. That's probably the most important one of all (for oddball stuff happening) next to the main ground to the engine.

Paul

 

got a picture? nice to see how you did it

 

I tucked the cable in underneath the battery rack. I'll be working on the other grounds this weekend.

 

Looking at the condition of the metal in the area, I can understand why it's time to "re-furbish" the grounds. You can definitely benefit from additional grounding.
By the way, the body grounds do not have to use full size battery cable. Nothing wrong with it! At least not usually. But it's overkill.
A few good lengths of 10ga wire are sufficient for most body grounding. But again, overkill is not a bad thing.

The only thing I can think of that might be trouble by using a big fat ground like that is that someday down the road if your main ground to the engine block ever fails, the current now has an alternate path to go to the body, but might not be enough to get back to the engine. Causing perhaps some trouble with some other wires.
But I don't know this for a fact. Just something I picked up from staying at a Holiday Inn Express one night! Maybe some of the more edumacated electricalators here on the forum can let us know if there is any real downside to oversizing the body ground.
Until then though, carry on for sure!

If you notice your headlights are not as bright as they could be, then a small jumper wire between that new ground at the regulator running over to the core support where the headlights get their ground might be called for. Normally not necessary, but you have a ton of surface corrosion on just the galvanized metal we can see. Might be causing a bad connection between the body parts.

And I may be wrong, but I have to mention it anyway. It's possible that you have the negative cable battery lug on upside down. See how the hole is chamfered there at the top edge? And there appears to be a slight gap near the top of the battery stud? The tapered hole in the battery cable lug might be upside down.
Worth taking a peek at at least. Sorry if you have to mess with it because I see you smartly put some grease, or anti-corrosion stuff on the connections. But hey, just about anything once done can be re-done.

Paul

 

That's what my plan was with adding another ground, glad to see I'm on the right track.

I laughed when I seen you said I put it upside down. I don't know why I didn't catch that in the moment, because I did the + side correctly. So thank you for pointing it out.

As for why I used that cable, I had it on hand already. I plan on using grounding straps from this point on. I can't seem to find the ground from the block to the firewall, Usually its on the intake, but it's not there. So I'll be adding from there to the firewall, then firewall to frame, then frame to bed. I believe that's the correct order?

I'm just glad I can actually drive it, and its such a relief to see the gauges working now and my stereo not cutting out every time I hit a bump.

 

Best reason there is!

I use those all the time. Nice pre-made ones on the HELP rack at the parts stores. Looks factory.
Although the factory also used Black wire sometimes, and even braided straps with black wrap too.
I mentioned 10ga wire because if you're going to be putting them here and there, sometimes it's easier to make your own to get it the right length.

They get removed by PO's all the time for some reason. I guess they figured just because the factory put it there does not mean it's important or anything like that!

Don't know there's any correct order or not. But it all sounds good. Not sure if the tail lights ground to the bed or not, but I've always needed a grounded bed because I put lights and other stuff on camper shells and such.
Sometimes they just don't work well enough without grounding the bed. Even though it's metal-to-metal already with the frame (I don't think Ford uses insulators between the bed mounts and frame. Do they?) and bolts, sometimes when they get old it's not enough.
Ford did however ground the body cab to the frame underneath. Bypassing the rubber mounts in at least two places. Serves to double-up on the engine-to-firewall ground, and reduces engine noise through the radio.

And speaking of that, Ford also grounded the hood to the body at the cowl. Possibly for RFI as well, but certainly for the under-hood lights when they were installed.

Definitely a comfort! The rest is cake and not necessarily an emergency anymore. But it's still going to be "better" when you're done.

Paul

 

Thank you for the pic. Greatly appreciated.