Hey Paul. I mean as in thats all the starter will do. Just make that noise. Both of them are doing the same thing. We had to jump both of them to get them to start this morning, wonder if we fried something??? Maybe that wire?
Which wire is it?
since my problem was on a 6.2 and i have not yet messed with a 7.3 starter (just got truck in winter and starter was almost new) i don't know exactly how to identify it, but most likely it is the wire going from the fender relay/solenoid that activates the solenoid on the starter. The 6.2 does not come with this set up and i actually had to rig it up this way because i was having the same problem. So i made sure to use an extra large wire for the above mentioned wire.
In my case, the stock set up was to have the wire going right from the key switch to the starter solenoid and eventually the heat would prevent enough amps to flow through the old worn out wire that passes just below the exhaust manifold. It really sounds to me like you have the exact same problem, especially the fact that it happened to two trucks today.
Come to think of it, the last time this happened to me on my 6.2 before i permanently fixed it as described above, i was under the van jumping the two terminals on the starter to get it to kick over, when my friend comes up to me (on a very hot day) and says his tractor won't start, it just makes a click sound when he turns the key!! He was having the exact same problem on the same hot day - so i went over and jumped the two terminals on the starter for a second just to give the solenoid a good flow of electric and it turned over, then i went up and turned the key and it cranked as normal and started.
i really hope you haven't pulled those starters yet!
paul
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