Dino Saga 051120 I volunteered to clean up the alternator while engine was out. It was oil soaked and rattled. Oh boy! It was supposedly re-built last year during engine overhaul. Decided to take it to my old alternator shop who have redone brushes every 3-4 years. They took it apart, called me and said: we have a problem. Turns out that rear bearing had come loose; shaft ran against housing and rotor was just eating into stator. I hadnt heard a thing. It charged just fine. Nobody had any info on Dino alternator as modified to drive US air pump. Book only shows cutaway of Euro version without extended shaft. There was no sign of any shoulder on shaft to keep bearing in housing. Steel bearing retainer ring had come loose and was just rattling around. Shop said that whole mess should go to a machine shop to re-do shaft and housing. Out of their league. I paid, went home and started in. Bolts buggered, housing really tight, finally got it apart. What a mess! At least it was fairly clean. First thing was to open up ID of front housing so it would go on and off easily. Sanding drum, layout dye and patience got rid of high spots. Put rear bearing in with O-ring only and put alternator together. Now that it was possible to slip things together without a hammer, I could see that the shaft had never had any more than 1mm actually touching the bearing ID. The bearing had moved forward a little and the shaft vibration moved it a lot. God knows how it has lasted 185,000 miles and 33 years. Now what? Shaft dia. was necked down 0.10 right where the bearing was supposed to go. Did not want to get shaft hot so could not weld up and re-grind. Did not trust JB Weld or any other filled epoxy as sole filler. Had some 0.062 mild steel so ran an experiment. Cut a strip 0.250 wide and rolled it around relieved area of shaft. Came out pretty good after working it with a smooth jawed vise. Relieved area is about 0.50 long so slid new ring to one end, coated shaft with JB Weld, slid ring to other end and coated that end with JB. Slid ring back and forth until JB coated everything, slid ring toward end of shaft and let set for a day. Turned steel strip down to OD of shaft. More better. Put back together and found that there was about 0.100 end play without the fan to lock rotor to front bearing. Slipped a 1/8 o-ring on shaft in groove left by rolled strip. Put together again and everything felt great. Thought about shaft. Probably made from a forging. That is an unmachined surface on necked down area. That was the bad starting point. If end of shaft had been same diameter all the way back, there would have been no problem. Other Dino owners with high mileage might want to take a look next time alternator needs brushes. Looked real close at steel bearing ring. There is a front and back. OD is serrated except edge toward fan. It had been pressed into housing bore and serrated marks were obvious in housing. Easy to get it back in because housing had been enlarged by pounding. Just the situation for red Loctite. Bought a new o-ring, put it in housing, installed bearing and held bearing bottomed out with a bolt/nut and a couple of big washers. Bearing was held square. I put Loctite 262 on ring serrations only. Pressed ring down gently and let sit for an hour. It was stuck fast and centered. Cleaned up all of the buggered screw heads. 1 dia. fiberglass cut-off disk in Moto Tool worked fine. Put everything back together and went back to alternator shop for final test. Did it still alternate? Yes! Cheated death again. John Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
