Tonti rotor removal

[brider]

Just a quick sanity check: The alternator rotor retaining bolt is a right-hand ("normal"?" thread, right? Like any other righty-tighty lefty-loosy bolt? It's been years since I removed one and I anticipate some heavy torque in a recessed-hex-head bolt to loosen it, so I want to make sure I'm turning the correct way. I'm ALWAYS leery of high-torque hex heads, once you round it off you're screwed. And speaking of rounded-off hex, that's why I'm removing the rotor, to remove the front cover to fix the rounded-off hex on my ATF pump assembly.

[Antietam Classic Cycle]

Yes, "normal" right-hand thread. Really shouldn't be that tight.

[jhem68]

Off the top of my head, I believe the torque spec for that bolt is 14 ft/lbs. And when removing the rotor do not apply any more than the recommended force after inserting the removal tool/pin. If the rotor doesn't come loose at the recommended torque spec then rap the rotor with a soft (rubber or copper or rawhide) mallet and it will pop off. Just be ready to catch it.

[John A]

Use a hardened pin , if it is regular steel it may deform and lodge in the hole.

[Tom H]

When using the correct removal tool or suitable substitute and the rotor will not budge. Use a regular hammer and give the head of the removal tool a good rap or two, normally pops right off.

Tom

[Chuck in Indiana]

When using the correct removal tool or suitable substitute and the rotor will not budge. Use a copper hammer and give the head of the removal tool a good rap or two, normally pops right off.

Tom

FTFY 

[bigbikerrick]

Are you replacing the rounded hex pump drive with something improved, as in cutting your own hex  from a tool?  How did it go down, has it been "slipping" for a while, and giving you warning, or was it a sudden backfire/ failure?
Good luck with the repair,
Rick.

[brider]

Thanks, all. I had a fuzzy memory of a threaded removal tool I used previously, with (2) different sizes of thread on it's shank, but could not find it after years of not using it. But I DID find a curious straight shaft in a ziplock bag with a seal, and after reading a bit here I realized it's the straight-pin removal tool with a replacement cover seal. How's THAT for luck!

To answer Rick's question: Yes, this is for my Cal 2 Auto slippage, it reared it's head suddenly coming home from work after a 5-day trip a couple of weeks previous that included climbing Mt. Washington in low gear, what I thought was a REAL test of the drive system. Worked flawlessly then. I still jerk awake in a cold sweat dreaming of what might have happened if that hex-drive failed climbing up the mtn.

After that climb, I had (1) single backfiring incident. Couple of weeks later the familiar symptoms appear. Coincidence? Experienced minds here say "no". I failed a hex a number of years before that after a chronic backfiring spell. In this case, it was a higher-than-normal revving during the 6-mile highway run coming home from work, then after the exit ramp stop sign very little hp being transferred to the rear wheel. I limped the 1/2-home. Convert owners who've experienced this know the feeling (physically & mentally).

I would LOVE to re-install an improved hex-drive element, but not sure what the current state-of-the-art is. My last (current) one is a piece of 6mm hex wrench cut to length. I recall Charlie actually mic'ed the cam and pump and had a custom shaft made that closed up some of the slop @ something above 6 mm, so I guess I'll wait to see what the mating elements look like before deciding.

[Antietam Classic Cycle]

Thanks, all. I had a fuzzy memory of a threaded removal tool I used previously, with (2) different sizes of thread on it's shank, but could not find it after years of not using it. But I DID find a curious straight shaft in a ziplock bag with a seal, and after reading a bit here I realized it's the straight-pin removal tool with a replacement cover seal. How's THAT for luck!

To answer Rick's question: Yes, this is for my Cal 2 Auto slippage, it reared it's head suddenly coming home from work after a 5-day trip a couple of weeks previous that included climbing Mt. Washington in low gear, what I thought was a REAL test of the drive system. Worked flawlessly then. I still jerk awake in a cold sweat dreaming of what might have happened if that hex-drive failed climbing up the mtn.

After that climb, I had (1) single backfiring incident. Couple of weeks later the familiar symptoms appear. Coincidence? Experienced minds here say "no". I failed a hex a number of years before that after a chronic backfiring spell. In this case, it was a higher-than-normal revving during the 6-mile highway run coming home from work, then after the exit ramp stop sign very little hp being transferred to the rear wheel. I limped the 1/2-home. Convert owners who've experienced this know the feeling (physically & mentally).

I would LOVE to re-install an improved hex-drive element, but not sure what the current state-of-the-art is. My last (current) one is a piece of 6mm hex wrench cut to length. I recall Charlie actually mic'ed the cam and pump and had a custom shaft made that closed up some of the slop @ something above 6 mm, so I guess I'll wait to see what the mating elements look like before deciding.

I had a piece of 1/4" Bondhus allen wrench surface ground to 6.2 mm. That fit snug into the cam and better into the pump coupling. 30k miles on it so far.

[brider]

I had a piece of 1/4" Bondhus allen wrench surface ground to 6.2 mm. That fit snug into the cam and better into the pump coupling. 30k miles on it so far.

Just as a point of interest: How do you surface-grind a 6-sided object and take equal amounts off each face? From .25" to 6.2 mm (converting as necessary) is around ~.006" per face. I love the idea, but that ain't much to be able to control it so you don't end up with a lopsided part. Just thinking out loud.....

[Antietam Classic Cycle]

Just as a point of interest: How do you surface-grind a 6-sided object and take equal amounts off each face? From .25" to 6.2 mm (converting as necessary) is around ~.006" per face. I love the idea, but that ain't much to be able to control it so you don't end up with a lopsided part. Just thinking out loud.....

I left the job to a qualified machinist friend, not sure how he did it.

[ray bear]

In reply to Briders question I have also done the modification that Charlie has done and set the 1/4 hex in a rotary table on the mill and a stone , nice light passes to keep the key from getting hot , you could do it with a dividing head ? Hmm , rotary table was the easiest for me and rotate to required degrees . Ray

[wirespokes]

I could grind down a hex key in the precision grinder. Chuck it up, grind, rotate 60 degrees, grind again, etc. Easy

[ray bear]

So long as what ever way you choose has a very accurate control of measurement  as each cut has to be exact to the thou or you end up with an eccentric hex and  only 2 or 3 sides of the key sharing  the load which would accelerate wear . A good table with an accurate  digital read out would be preferred . it certainly is the Achilles heel of the convert and thought by now some of the guys that have tried like road kill may have come up with the perfect solution to that drive. 

[Moparnut72]

Just as a point of interest: How do you surface-grind a 6-sided object and take equal amounts off each face? From .25" to 6.2 mm (converting as necessary) is around ~.006" per face. I love the idea, but that ain't much to be able to control it so you don't end up with a lopsided part. Just thinking out loud.....

That was the first thing that came to mind. Our machinist friends here came to my rescue but I am not familiar with those kinds of machines. We had a surface grinder in the shop which was mainly used to grind rings to fit pistons.
kk

[Chuck in Indiana]

Pfffft. Just put it on a magnetic chuck on a surface grinder. Easy Peasey..

[Antietam Classic Cycle]

Pfffft. Just put it on a magnetic chuck on a surface grinder. Easy Peasey..

I think that might be the way my friend did it.

[brider]

Pfffft. Just put it on a magnetic chuck on a surface grinder. Easy Peasey..

Please explain this operation to me like I'm a 4-yr old. The setup, what the chuck looks like, what the surface grinder looks like, how the grind depth is controlled, etc, with pictures (best) or hand-waving if necessary.

[Antietam Classic Cycle]

Please explain this operation to me like I'm a 4-yr old. The setup, what the chuck looks like, what the surface grinder looks like, how the grind depth is controlled, etc, with pictures (best) or hand-waving if necessary.

The video in this auction should answer your questions: https://www.ebay.com/itm/285562109464

[John A]

The video in this auction should answer your questions: https://www.ebay.com/itm/285562109464

Wow! I’m in love !

[Chuck in Indiana]

Mine is even older.. I gave $300 for it back in the day. 

[brider]

The video in this auction should answer your questions: https://www.ebay.com/itm/285562109464

And it's made in St. Louie! That's where I bought my first & second Guzzis! I love it for it's functionality and American art form.

Maybe I missed it: Is there a way to zero-out net contact with the surface you're grinding, then set the grind depth on a vernier scale on the vertical-grind adjustment? How else could you accurately set the grind depth?

[ray bear]

your very correct Brider they havent worked that out yet, you will end up with an eccentric hex which may only be contacting on 2 or 3 sides and will destroy a very hard to get pump drive and camshaft prematurely  . you must zero and be able to cut within thousands of an inch and each side of the hex must be identical ,I have a convert and have performed that modification do it right

[Chuck in Indiana]

And it's made in St. Louie! That's where I bought my first & second Guzzis! I love it for it's functionality and American art form.

Maybe I missed it: Is there a way to zero-out net contact with the surface you're grinding, then set the grind depth on a vernier scale on the vertical-grind adjustment? How else could you accurately set the grind depth?

Grinding machines in general are *very* accurate. Even my antique surface grinder's feed wheels are graduated in half thousandths. Instead of sloppily plunging into the workpiece like the guy showed on the video    you slowly kiss the surface. From that point you can easily take off .006", turn one flat,cut, turn, then feed down another .006" to do the other 3 sides.

[Moparnut72]

The surface grinder we had would feed by itself. The do all the rings for a 7 cylinder radial would take a good part of the day. It hardly took anything off on each pass.
kk