Lately in the moining when its cold, i go to start my truck, and the starter just spins. Finally after 5 or 6 times it engages perfectly. And it will not do it the rest of the day, or if it is warm out. I had a new flywheel and starter and solenoid put on a month ago. Any ideas on what it is?
The bulge on the side of old Ford starters is where one of the pole shoes swings out of the windings to retract the drive gear. When the relay sends power to the starter, the magnetic field of the windings pulls the pole shoe inward, pushing the starter drive gear into the ring gear on the flywheel/flexplate. When you release the key & the relay shuts off, a heavy spring pushes the pole shoe back out of the starter winding to retract the drive gear.
It sounds like the hinge mechanism for yours is binding somehow, but it's just a roll pin thru a thick steel arm. You can see it & test it by removing the small screw from the back of the bulge on the starter & removing the cover - this will expose the roll pin & the swinging pole shoe (a block of steel welded onto the arm). You should be able to push it into the starter at least partially (using a LOT of hand force until the drive hits the ring gear). Look for signs of binding or misalignment: shiny arcs on the sides of the shoe or arm; blackness near the hinge pin; metal shavings; etc. You CAN operate the starter without the cover in place as long as you're clear of the pole shoe (it can pinch the $#!T out of you if you're holding it wrong) to see if you can observe the binding.