A12 - time to get busy

I only had time to get the alternator about half apart - I think it's going to turn out to be junk. I could only turn the rotor about 1/8 of a turn. OTOH it was also full of trash that I shook out of it. I'll get it fully split apart tomorrow and will know more.

I found a 69 date stamp so chances are good it's the original part from the car. I don't know how to read the month on it. Doesn't really matter though, other than I'm trying to keep all the parts car parts that I can. Call me weird.
 
Too bad you couldn't hollow out the round back alt case and stuff the guts from a late model Nippon-Denso style alt inside it. :unsure:




...and you're weird. 🤣
 
The alternator is pretty much shot but I think it's rebuildable. The rotor won't even turn with the case split. I tried knocking it out (after releasing the bearing retainer) but no luck, and I couldn't find anything to rig it up in the press either. But that bearing is at least worn out, at worst locked up with damage to the rotor.

I kind of hesitate to go further with it out of worry that I will screw up the soldering or that I'll end up with $50-60 in a rebuild kit but the dumb thing still won't work. Maybe both!

I think before I make a decision I'll drive out to the parts store to see if they've actually got a single-field round back on the shelf or if they're all square backs with some kind of grounding adapter on the ground field. If they've got something I can deal with I may go ahead and fork over the $$ to get one while the getting is good.

$40 core - makes me consider giving the old one up as a trade in. Maybe I could get $50 for it to someone needing a date code, probably not. They made a million of them and they're all the same other than that tiny little date stamp.

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I've fixed many of those with all different maladies. It takes a special tool to remove the pulley and the outer bearing. It's in my garage. :giggle:
 
68R/T said:
I've fixed many of those with all different maladies. It takes a special tool to remove the pulley and the outer bearing. It's in my garage. :giggle:
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I've got the pulley puller and the case is already split. I'm waiting on the time to set up the press to remove the rotor, then the bearing comes off. I've seen that a small bearing puller is what you need to pull the bearing.
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It takes a while to get there but eventually he does
 
My pulley removal tool is deeper and the bearing removal part is to flip the 2 internal parts that grab the pulley & bearing. It's an incomplete video, he never shows removing any internal parts or how to test & remove diodes. To test diodes you need a powered test light. the test light will light in one direction only, not both. If it lights in both directions, It's shorted, if it doesn't light in either direction, it's open circuited.
 
I've just got a HF pulley tool but it's worked on several PS pumps so far, and it worked on this alternator. I don't remember exactly how it works but you can juggle the parts and use it as an installer too,

I was planning on doing what the video did - new bearings, new brushes, look for shorts, see if it charges. If yes, done. If not, then evaluate the diodes. Which is why I'm considering just buying a reman and forgetting about it. I won't need it for months, and worse comes to worst I've got a good square back I can ground the field on and use. Or I can just drive about a mile to the parts store.

If more is bad in it, the parts would end up costing more than a reman. Bearings and brushes alone was 60-70 by the time I paid shipping but I looked at rebuild shops not ebay. I just checked ebay and the bearings and brushes are $20 but this seller doesn't have a full kit with diodes for the single field part. Apparently from a quick look-round, nobody else does either.


TBH I'm more concerned about screwing up the soldering than I am anything else about it.
 
I wonder if that rebuilt alternator in the video is going to work with the screw missing from that wire coming off the positive stud? Other than that, looks like a pretty comprehensive tutorial on the rebuild.

I'm kinda curious about how well that little add-on box thingy works though? I've never seen one of those before. What does it do exactly?
 
gomopar440 said:
I wonder if that rebuilt alternator in the video is going to work with the screw missing from that wire coming off the positive stud? Other than that, looks like a pretty comprehensive tutorial on the rebuild.
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I didn't notice the screw :D I could see me doing that, but also see me going back and editing the video. That's why I don't make videos.

gomopar440 said:
I'm kinda curious about how well that little add-on box thingy works though? I've never seen one of those before. What does it do exactly?
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The add on box is just an stock replacement electronic voltage regulator with a pigtail, miniaturized so you can just screw it to the alternator.

I do not understand why anyone would do that instead of just using the one on the firewall and the wiring harness it came with. People gotta make money someway.

You need an electronic VR for electronic ignition so you can upgrade to the 70-up system, or buy one of these, which is what I did.

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I was putting the alternator back together and toss it back on the shelf to think about later, when I realized I've got no idea how to hold the + brush out of the way so the rotor can go in the bearing. So I put it on the shelf in pieces.

The trunk seal is still stuck so I'm good to go on that account. I haven't fully latched the trunk yet but I set it down and could hear the latches hitting. It's expected that the seal will make it hard to close and possibly hold it up along the sides until it settles in.

I had to use a two-jaw puller to get the slinger off the crank. It was either that or wreck it with a screwdriver.

I'm in the process of taking the T-bars out to have a good look at them. The stupid bodyshop used a stupid pair of vice grips and a stupid hammer to get them out so I have to check them. I think they're original A12 parts but I thought that about the rear brakes too. I've got nothing handy to compare them to so they might be /6 parts. I'll check that too.

FWIW the stupid bodyshop put the stupid boots on backwards so the t-bars had to come back out no matter what. If I run the big-tube Hooker SuperComps I'll have to take them back out one more time. It's either them or the Schumacher shorties I bought for the duster when it had a big block. Probably going to be the Hookers but that reminded me I need to check that you can bolt to the collector on them. Race parts.

Also, on turning the engine upside down with the top end in it, I decided I didn't want that kind of a mess on the floor. It seems to me like there's going to be a lot of oil in the heads, rocker arms, etc and that is all going to drain out when it's upside down.
 
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b-body-bob said:
I was putting the alternator back together and toss it back on the shelf to think about later, when I realized I've got no idea how to hold the + brush out of the way so the rotor can go in the bearing. So I put it on the shelf in pieces.
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Assemble the alternator and save the brushes for last, then they slip right in.
 
68R/T said:
Assemble the alternator and save the brushes for last, then they slip right in.
Click to expand...
That's the way I tried first. I wasn't able to get the brush holder between the fins on the non-rotating rotor. So then I tried putting them in first, when I noticed there's no tiny hole to stick a toothpick in to hold the brush back. (I remember those from my youth working in a garage). So I just bagged it all and put it on the shelf.
 
I had a time getting the brush holder out and I'll break it before I get it back in. There's no juggling the fins back and forth to work it in - it won't turn without prying which kind of kills any chance of finagling the holder where it goes while moving the rotor around. The thing won't even turn so no need to worry about getting the brushes installed now.

After 48 hours, I shut the trunk. It's kind of hooved up in places, but the seal will settle down eventually.

I looked at my candidate transmission last night. It's got a big B&M sticker on it, maybe it was built by them, maybe it's just a sticker. It shifted great in the Duster behind the 400 though. Definitely has a shift kit in it but is still full auto. The torque converter sucked but I've got a couple of fixes for that. It was kind of surprising that it was built in Jan 1966, but that's modern enough to be good to use. At least I think it's past the oddball parts phase.

I've got the race trans that came in it originally but do not want to detune that thing to use a normal valve body. RMVB is a PITA on the column shifter and I'm not putting the B&M floor shifter back in it. The governor is long gone, there's a bolt in sprag, etc, etc. It's got some setup where you put more clutches in the drum than it's designed for. I think that's why the dumb thing wants to creep forward in neutral. So I'm not planning on messing with that unit for this car.
 
Had a bit of an adventure with a torsion bar last night.


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You see my TB tool there just past the end of the speedo cable, and the torsion bar to the rear.

Also note what side of the torsion bar crossmember the tool is on.

This car came with a bunch of crap welded to the floor as part of the roll cage, that I saw no reason to cut out. Of course a piece of it is right in the way.

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I wailed on it to get it out. Don't know how it's going to work going back in. If I can get it in the hex I'll just wail on it again.

Worst comes to worst I'll break out the sawzall and worry about making it pretty again later.

It's only on the driver's side, because race car.

FWIW the cheapish Amazon.com torsion bar tool worked great, and I got my valvetrain disassembly tray so I can remove the rockers and all that to get at the bottom end.
 
The top end is off the engine, and things have been evaluated ... I haven't finished taking photos yet.

The lifter lobe face shows it's been spinning. In fact the lifter body shows that too. There's the typical band at the bottom, then I've got one above that showing evidence it's been spinning a long time. There are some vertical scratches too.

There are some odd tiny black specks on the face of most all of the lifters, all sort of in a line. I don't know what to make of that. The cam shows age and use too. It's one of the early radical 509 hydraulic cams before they changed the lobe center to calm it down some. The jury is out on reusing it - if it stays a 440 I may move up to something like the old 590 solid purple shaft.

The cam bearings are in one piece and show signs of scraping so they've been replaced at least once but look to be usable.

Pistons are L2355, +.030, forged. They're about .018 in the hole measured with a feeler gauge. The bores are smooth, no cross-hatch left. There is no ridge or noticeable damage. I noticed one tiny speck of rust or something that wouldn't just wipe off in one cylinder. There may be more. It's going to need honed anyway it goes. The block's destiny probably depends on how out of round things are. If possible I will hone it and go.

The heads are 72-3 346s, basically 452s (ports are the same). They may be the originals for this block. Someone has put some work into them. It's hard to say how much, but after looking at another set it's obvious the grinder's been around the valve stem and the casting crap has been smoothed out. The engine side has been sprayed with chem-dye, but there is still > .020 lip at the edge of the chamber so I don't think they have been cut. Maybe somebody did that to check level on the deck surface the hard way? Don't know.

There don't seem to be any sunk valves unless they're all sunk. The valve tops are pretty much level, side to side. These have double valve springs with dampers. Why? Maybe race car? I don't have a valve spring tool that's up to the task so I don't know what the stems or seats look like. If that all checks out OK I think I can get by with no machine work here. If these go back on I will probably run a steel shim gasket.

I have another set of heads that could be useful. Those are 915 HPs, big valves, closed chambers. These are stock castings, never touched by a grinder. At least one of the exhaust side bolt holes is stripped and won't hold a stud or bolt. That might end up needing a machine shop to put threads in the open hole. I don't think a heli-coil is the solution. I stuck a straight edge across the valves on one of them and they're kind of all over the place. I see them needing a machine shop to make a good set, and I'm not sure they're worth it to me. OTOH I just checked and you end up with nearly $2k in a set of 440 source heads once you're done.

I've also got four other 452 heads, two that were involved in the infamous intake full of coolant event. If Jass was here he'd post a photo. Anyway, I think at least one of those is cracked because how the hell else do you end up with coolant in a big block intake? IIRC the other two look like a monkey tried to port them with a chisel and a file.

Next stop, bottom end, where we find out how many cubic inches this engine is going to end up with. That all depends on the crank. If it just needs polished, I'm gold. It's forged; the engine is a non-HP 72 model motor. I have confidence in it; there was plenty of oil pressure when last started. But if it's chewed up it might be time for a stroker crank.

Another factor is the bore. I hope I can just hone the crap out of it and move on with my life. But if it has to go to .060, that means new pistons, then rod resizing because the rod/pistons need the machinist to press the pin so why not, possibly balancing, so maybe I should start adding it up and thinking more about that stroker kit.

But I really hope to end up a 440 in the end simply because that's expensive enough.

FWIW I'm starting to work, slowly, on the door mechanisms and glass too.
 
Not a lot, but it tends to be influenced by any mods and the type of use. If you're concerned just add some lead additive occasionally
 
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