Why is it that the threaded hole in the top of the new tie rod bolts, where the brass twist oiler goes, is not cut deep enough to allow the brass oiler to go more than half way in? What size tap should I get to clean and deepen these threads? It's the same darn thing with the repop spring shackles - won't allow the oilers to go very far.
Because they're tapered pipe threads - 1/8" p.
I took an extra tap 1/8 NPT and cut the first 1/3 of it off.It allows you to get the hole tapered a little more.