HMMWV Alternator problem

[KKroger]

Belts off yesterday evening on my way home. had a tapping noise in the vicinity of the alternator but could not nail it down.
At any rate the belts came off and got F'd up. Then I noticed the pulley was loose. and very loose...

then today when it was light out I removed the alternator to check it all out. and OH BOY!
I have ordered a new pulley already and I will pull the alternator and fix it up on the mill and see if I can mill a keyway on the other side of the shaft.

Someone had hogged out that key slot for the woodruff which is absolutely the wrong key it is too wide for the keyway in the pulley, they ground it out so that it would sit at an angle and it had way too much play and wallered it out a lot. Always something. this had to be done at the ARMY!

daily driver and can't find a loaner!

 

[Mogman]

Actually they use woodruff keys, it just looks like it got loose and beat itself up.

Key, Woodruff Woodruff #15

Real4WD - MS35756-17 - Key, Woodruff Woodruff #15 5315000124553, NSN 5315-00-012-4553

real4wd.com

 

[KKroger]

Actually they use woodruff keys, it just looks like it got loose and beat itself up.

Key, Woodruff Woodruff #15

Real4WD - MS35756-17 - Key, Woodruff Woodruff #15 5315000124553, NSN 5315-00-012-4553

real4wd.com

Actually the woodruff key used was the wrong side too thick like I say it won't fit the groove in the pulley.

 

[juanprado]

What flavor of Alt 60amp , 100, 200 or 400?
I assume v belts so likely 60 or 200. Were all the mounting bolts and brace snug? Brackets?

 

[KKroger]

What flavor of Alt 60amp , 100, 200 or 400?
I assume v belts so likely 60 or 200. Were all the mounting bolts and brace snug? Brackets?

I believe this one to be a 200, it has the 14V regulator on it as well. I can look for sure later on here.

 

[juanprado]

That answers the question with the regulator it is probably 200. Some older models had 100 but that is not as common as the 200. The 400 would power the space shuttle and weighs 17 tons...Lol

Damn shame as the 200 is a small fortune. With a new key weight and pulley with a lock washer under the nut, you might be ok. That is what I would do before forking over a mortgage payment for an alt.....

Is the nut ok and the threads on shaft?

 

[Gastrap]

Keyway is knocked out from a loose pulley hammering on it, not modified. If you put that new pulley on with some 680 Loctite and primer, it's not moving again, key or no key. Welding that mess up may warp the shaft, and milling a new one 180° off may weaken it too much.

I often salvage wasted keyways and worn shaft/bearing fits with 680 Loctite on farm equipment when the customer wants a temporary or cheap fix. A lot of that stuff is fine years later.

 

[KKroger]

That answers the question with the regulator it is probably 200. Some older models had 100 but that is not as common as the 200. The 400 would power the space shuttle and weighs 17 tons...Lol

Damn shame as the 200 is a small fortune. With a new key weight and pulley with a lock washer under the nut, you might be ok. That is what I would do before forking over a mortgage payment for an alt.....

Is the nut ok and the threads on shaft?

Nut and threads are fine.

 

[KKroger]

Keyway is knocked out from a loose pulley hammering on it, not modified. If you put that new pulley on with some 680 Loctite and primer, it's not moving again, key or no key. Welding that mess up may warp the shaft, and milling a new one 180° off may weaken it too much.

I often salvage wasted keyways and worn shaft/bearing fits with 680 Loctite on farm equipment when the customer wants a temporary or cheap fix. A lot of that stuff is fine years later.

I'd be willing to try the locktite, I wouldn't mill a woodruff keyway in there just one for a square. the key though that was in there will not fit the keyway in the pulley it is too thick, there is a spot beat out in the center of the pulley keyway that is the length of the key and there is NO way that key ever fit the keyway in the pulley. the only way it fits is if the key sits at an angle so just a corner goes in the pulley keyway. not sure where to get a 7/8 lock or star washer the Nut is a military lock nut, 1-1/16" hex the shaft is 7/8" I'll look though.

 

[Gastrap]

Sounds like some "good" mechanic was trying to fill a gap

If you're going to try to salvage it with 680 Loctite just put a little on the nut too and skip the lock washer. It will require 400° of heat to get it apart next time anyway. It'll work without the primer, note that if do use primer you won't have much time to get things tight before it sets up. Not a proper fix, but it may get you by a long time. Either way, let it cure 24 hours before putting a load on it.

 

[KKroger]

Sounds like some "good" mechanic was trying to fill a gap

If you're going to try to salvage it with 680 Loctite just put a little on the nut too and skip the lock washer. It will require 400° of heat to get it apart next time anyway. It'll work without the primer, note that if do use primer you won't have much time to get things tight before it sets up. Not a proper fix, but it may get you by a long time. Either way, let it cure 24 hours before putting a load on it.

I'll try it and plan to get a rebuilt alternator later on. with new key and pulley and a nut. I've done repairs to hydraulic equipment before turning the rust off with the lathe and making a sleeve to repair it then turning the sleeve to final dimension and finish. so that it will seal again. Used sleeve mount for that, I use 680 at work making brass standards all the time.

 

[KKroger]

Put it all back together this morning Friday the 14th Loctite sat since Tuesday the 11th. drove it to the base this morning and all is well much quieter, volts gage hovers under power at top of "Green" and at idle "Bottom of Green"

 

[TOBASH]

You can make a semi- woodruff. I suggest it.

Make a pattern with a central hole for the main bolt and a smaller hole for a dowel that allows you to drill half pulley and half alternator shaft. This will be really tight and near the threads. Tap in round stick dowel and use nut to tighten AND hold in place. This is similar to what one does with a supercharger to keep the harmonic balancer from spinning. Also a great way to keep 6.2 harmonic balancers from grenading

You could also just use a Dremel to make a new woodruff space if the Locktite fails.