Ok, a bit related to a posting in the NH buying forum. 1998 TN55s with NH loader (33LA?). Anyhow, the loader is a quick detach unit (like most), that mounts via posts on the sides of the engine. They mount to the bell housing and also to a casting bolted to (and) in front of the engine block. Font axle hangs off of this, etc.
I noticed that one of the two bolts that attach to the casting in front of the engine was a brassy colored grade 8, versus the smaller gray (NH color). I had tightened them up once, but found them loose the other day. I should say I found the grade 8 bolt was loose, as the factory bolt was sheared off at the casting.
Oh, great joy to have something to fix that is large and expensive looking! Arrrgh....
So, got the loader off and the mount off. Found a slight crack (not spreading) in the part of the mount that goes back to the bell housing and the lower part of (I presume) the transmission housing (might even be the bell housing, haven't looked that hard). Easily fixable, will grind out part of the crack, weld it, then turn it over and repeat.
Found the bell housing bolt was a grade 5, 3/4" dia bolt. Seems that a metric 20 x 2.5 tpmm has the same pitch, but is a bit larger in diameter than a UNC bolt. Lazy jerks....
Fortunately, the threads aren't damaged, so that will be an easy fix.
Now the fun part! Pulled the 7/8" bolt out of the front. Seems the bolt wallowed out the hole it is in. Drilled it out to 15/16" and acquired an 1" -14 tap and bolt. Have it about 1/2 tapped and it is obvious that the the hole isn't quite round, as I have an area that is not quite threaded. Now wondering what to do. Thinking about thread inserts, but wary of trying to drill a hole much larger with my 1/2" drill. Lot's of stop/start as the bit hits and stops most of the time (hard to control feed rate).
The next fun bolt is the sheared off one. Got it drilled out, thinking I had it mostly centered. Turns out mostly is the correct term. I had it almost tapped (7/8"-14) when the one piece of bolt came loose (at the bottom of the 2" deep hole, chip is about 3/4" long). After pulling it out I found the threads I had cut were damaged. Probably didn't remove the chips enough. So now thinking a threaded insert will have to be used.
Whatever I end up with will lead to drilling the 1" thick plate of the loader mount.
So, ideas for drilling it out/insets? Specs for drilling if you have them.
Need a slower drill as well. May see about renting one. At the rate things are going, likely get more informed and take it to a local repair shop, as you can only go so far with buying large bits and taps (helicoil as well) before it is time to pass it on....
I noticed that one of the two bolts that attach to the casting in front of the engine was a brassy colored grade 8, versus the smaller gray (NH color). I had tightened them up once, but found them loose the other day. I should say I found the grade 8 bolt was loose, as the factory bolt was sheared off at the casting.
Oh, great joy to have something to fix that is large and expensive looking! Arrrgh....
So, got the loader off and the mount off. Found a slight crack (not spreading) in the part of the mount that goes back to the bell housing and the lower part of (I presume) the transmission housing (might even be the bell housing, haven't looked that hard). Easily fixable, will grind out part of the crack, weld it, then turn it over and repeat.
Found the bell housing bolt was a grade 5, 3/4" dia bolt. Seems that a metric 20 x 2.5 tpmm has the same pitch, but is a bit larger in diameter than a UNC bolt. Lazy jerks....
Fortunately, the threads aren't damaged, so that will be an easy fix.
Now the fun part! Pulled the 7/8" bolt out of the front. Seems the bolt wallowed out the hole it is in. Drilled it out to 15/16" and acquired an 1" -14 tap and bolt. Have it about 1/2 tapped and it is obvious that the the hole isn't quite round, as I have an area that is not quite threaded. Now wondering what to do. Thinking about thread inserts, but wary of trying to drill a hole much larger with my 1/2" drill. Lot's of stop/start as the bit hits and stops most of the time (hard to control feed rate).
The next fun bolt is the sheared off one. Got it drilled out, thinking I had it mostly centered. Turns out mostly is the correct term. I had it almost tapped (7/8"-14) when the one piece of bolt came loose (at the bottom of the 2" deep hole, chip is about 3/4" long). After pulling it out I found the threads I had cut were damaged. Probably didn't remove the chips enough. So now thinking a threaded insert will have to be used.
Whatever I end up with will lead to drilling the 1" thick plate of the loader mount.
So, ideas for drilling it out/insets? Specs for drilling if you have them.
Need a slower drill as well. May see about renting one. At the rate things are going, likely get more informed and take it to a local repair shop, as you can only go so far with buying large bits and taps (helicoil as well) before it is time to pass it on....