Keep spacer in place so ears won't break.

If a spacer is not in place when installing the older style alternator bracket, your HMMWV's alternator ears soon might not be either.

A big strain is put on the alternator ear as the brace nut is tightened when the spacer is missing. That's why forgetting to re-install the spacer at the rear alternator brace can lead to a broken ear on 60-amp, 100-amp, and 200-amp HMMWV alternators. When the ear breaks off, the alternator has to go to the rebuild shop. But this can be prevented if you use a spacer.

On 60-amp and 100-amp alternators, use spacer, NSN 5310-01-292-5354, with brace, NSN 5340-01-293-0125. On 200-amp alternators, use spacer, NSN 5310-01-337-7034, with brace, NSN 5340-01-292-8404. Eyeball paragraph 4-2, step b.3, and paragraph 4-4, step b.2 of TM 9-2320-280-20-2 for more details. Note that a spacer is not required for alternators mounted with the steel through-bolt style support bracket. But when the TM calls for a spacer, remember that if the spacer is in place, your ear won't break.