I bought a new solenoid and hooked it up. I must have it backwards. It cranks and sparks like crazy when I put the battery positive on. I swaped wires and it still does it. The little red and black wire, where do those go? Black to the "I" and red to the "s"? Then battery positive to the side with the I and the wire to the starter on the s side?

 

The small wires should be (1) brown and (1) Red w/ blue trace. The solenoid should be mounted so the battery terminal on the "S" side points to the battery.
Positive battery cable goes to the 5/16" post on the "S" terminal side, the other 5/16" terminal has the cable that goes to the starter.
The brown wire goes to the "I" terminal, the red w/ blue trace wire goes to the "S" terminal.

 

and make sure it's grounded well (both bolts to the mount location on the fenderwell).

 

Where did you buy this new starter solenoid? Who made it? They are mostly junk these days and will often cause lots of problems down the road. Try installing the old one and see if the fireworks goes away.

 

Some what of a upgrade: 97 f250 Starter Relay / Starter Solenoid:

 

Thanks for the help. I'm actually returning the new one tomorrow. Its a Standard brand. The old one wouldn't work sometimes and I would have to hit it to start the truck so I won't put it back on.

Out of curiosity how does the upgraded 97 solenoid wire up?

 

Same way as old.

There is an S and I terminal like the old.

Relay ECH STH404 | Buy Online - NAPA Auto Parts

 

Just installed the new solenoid. Wires it correct. The other one was bad. I measured resistance and had it at all poles. The new one red OL at all of them. Starts fine. But now the starter is hanging up. When I shut it off, it keeps cranking. Even with the key out. I had to pull The battery cable again.

 

That also sounds like a bad solenoid. I had a new one from o'reilly that would do that exact thing. I had to rap the top of it with a mallet to make it quit. I bought a NOS on eBay to replace it

 

X2 on NOT the starter, but a welded solenoid...time to get another new one. Meaning fenderwell mounted starter solenoid.

 

I just went through the exact same thing. Had 2 pieces of junk right out of the box. Scares the crap out of you when you put the battery cable back on and the starter lights off! Glad it wasn't in gear!

When I took the second one back, I had them order me the 'premium' one in. It's baby blue with a copper covered mount. Works like a champ.

 

I'm interested in 460ME's comment about using a '97 F250 solenoid instead. I'd think the electronics in it are better?? than what was used in the standard 70's model, no? Anybody done this?

 

Got another solenoid today. Its a blue one. I guess its suppose to be better then the others. It was $5 more which I dont care, as long as the freaking thing works.

 

These things have always amazed me. They are identical for a lot of make and models even including jeeps and who knows what all. Like millions of vehicles. Even winches have them and who knows what all equipment. Even my bobcat has the same one. And they have never changed (except for the later style). And now the later is the exact same in everything including winches.
I swear it's got to be a Chinese product for every third one is a piece of crap. And you can get them online for $10 all day long. But they are a very important piece. You'd think aftermarket would eye production of a better product???

 

The new solenoid worked like a charm. I used the Standard Blue Streak professional series. Instead of the cheaper Standard.