23tub
Member
Ever had to ruin an alternator pulley nut to get it off? I did. Damned thing must've been soaked in salt water. Anyway, getting it off was one problem. Definitively ruined the nut.
Now to put it back on. What size nut? Thread gauge says 20 threads per inch. Metric 1.25 pitch is pretty close too. Measured the shaft diameter at .667", so guessed 5/8-20. Bought a die. Too small. Back to measurements. Broke out Machinery's handbook. The next larger size, 11/16-20 should be .6781"-.6862" major diameter. Measured .656". Minor diameter is supposed to be .6494"-.6537". Measured .6415". Reasonably close....
Closest metric size is 17mm - which is what the shaft measures coincidentally? They don't list a 17x1.25 nut, so used 17x1 for dimensions. Major diameter is supposed to be 17.00-17.304mm. I measured 16.72. Minor 15.917-16.153mm I measured 16.29. M17x1.25 nuts do not seem to exist online, although I did fine dies that size, so the nuts must be around somewhere. 1.0 and 1.5 pitches definitely will not fit, so I'm guessing that what I need is an 11/16-20 nut. I ordered a die to clean up the threads, so we'll see.
Out of frustration, I ordered a pulley with nut and washers from Summit (I usually get my orders the next day). Finding 11/16-20 nuts online isn't OVERLY difficult, but this way I get a new pulley and hardware.
What started this? A squeaky fan belt on the 396 in my tub. I figured that a mid mount on the passenger side would be cool. Looked at mounts from March and Billet Specialties. Bought the one from March. Mistake. Should have bought the one from Billet Specialties. March's instruction sheet says that my cylinder head may have either a 7/16 or 3/8 hole tapped in it. Mine happened to be 7/16. The mounting hole in the alternator is 3/8. Billet Specialties kit has provisions for this. March, on the other hand does not - so I drilled the alternator out to 7/16. Not killer, but an unexpected bother. Then the fun started. Mounted the alternator, and put on a fan belt to adjust tension on it. The fan on the alternator hits the Heim joint they use for the tensioner. Not mentioned anywhere that it MAY need to be changed. I suspect that Billet Specialties has the same issue. Ordered a March alternator fan from Summit, but can't try it out until I get my nut problem sorted out. I was leery buying anything from a company whose initials are BS, but if I ever have to do it again, it'll be BS parts for me. At least they thought of 1 potential issue.
Has anyone else run into these problems or am I the only lucky one?
Now to put it back on. What size nut? Thread gauge says 20 threads per inch. Metric 1.25 pitch is pretty close too. Measured the shaft diameter at .667", so guessed 5/8-20. Bought a die. Too small. Back to measurements. Broke out Machinery's handbook. The next larger size, 11/16-20 should be .6781"-.6862" major diameter. Measured .656". Minor diameter is supposed to be .6494"-.6537". Measured .6415". Reasonably close....
Closest metric size is 17mm - which is what the shaft measures coincidentally? They don't list a 17x1.25 nut, so used 17x1 for dimensions. Major diameter is supposed to be 17.00-17.304mm. I measured 16.72. Minor 15.917-16.153mm I measured 16.29. M17x1.25 nuts do not seem to exist online, although I did fine dies that size, so the nuts must be around somewhere. 1.0 and 1.5 pitches definitely will not fit, so I'm guessing that what I need is an 11/16-20 nut. I ordered a die to clean up the threads, so we'll see.
Out of frustration, I ordered a pulley with nut and washers from Summit (I usually get my orders the next day). Finding 11/16-20 nuts online isn't OVERLY difficult, but this way I get a new pulley and hardware.
What started this? A squeaky fan belt on the 396 in my tub. I figured that a mid mount on the passenger side would be cool. Looked at mounts from March and Billet Specialties. Bought the one from March. Mistake. Should have bought the one from Billet Specialties. March's instruction sheet says that my cylinder head may have either a 7/16 or 3/8 hole tapped in it. Mine happened to be 7/16. The mounting hole in the alternator is 3/8. Billet Specialties kit has provisions for this. March, on the other hand does not - so I drilled the alternator out to 7/16. Not killer, but an unexpected bother. Then the fun started. Mounted the alternator, and put on a fan belt to adjust tension on it. The fan on the alternator hits the Heim joint they use for the tensioner. Not mentioned anywhere that it MAY need to be changed. I suspect that Billet Specialties has the same issue. Ordered a March alternator fan from Summit, but can't try it out until I get my nut problem sorted out. I was leery buying anything from a company whose initials are BS, but if I ever have to do it again, it'll be BS parts for me. At least they thought of 1 potential issue.
Has anyone else run into these problems or am I the only lucky one?
