Fuel Shutoff Solenoid acts up...then quits

[fortunate1]

This past weekend my truck wouldn't fire up a couple of times, even though the engine turned over fine. I suspected the solenoid, and pulled up on the shaft while the key was on (just as I've heard others in their posts on TDR). That did the trick. The engine would start other times without doing this.

So I took some time today to remove the solenoid and clean it. I also did the "bicycle tire tube" repair since the rubber boot had some holes in it from dry rot. I also replaced the relay for the solenoid in the fuse/relay box with the Radio Shack #275-0226. The relay wasn't the problem, as I switched relays from other functions (horn, A/C, etc.) and everything still worked fine. The other large relay at the top of the firewall won't switch out like the smaller one in the box. It has wires that run directly into it. Could this relay be the problem? How do you change it? Cut the wires and re-splice?

Now the solenoid has quit working altogether. The shaft won't go up OR stay up with the key in "run" position. I tried to get the solenoid to actuate by putting 12 volts directly to it. No movement at all. I can reach under there and pull the shaft up by hand; it just won't stay, and the spring pushes it back to the "shutdown" (extended) position.

Any ideas? Time for a new solenoid? Ouch...Cummins Atlantic wants almost $300 for one.