348 alternator removal & rebuild

Don't want to clutter up this thread, but as another data point on our 348 alternators, I've posted some pics of the alternator on my 1992 348 on the thread I've been using for my Major inspection. For anyone interested ... here's a link....

http://www.ferrarichat.com/forum/showthread.php?p=137830637#post137830637

 

Part # 156703 has now been replaced by part # 199830 (760mm), this is also the AC comp belt for the 355`s

Great thread Ernie, many thanks.

Regards,
Phil.

 

348 Brothers! Just posting an update on latest on my alternator rebuild. If you want to see pics, you can check my Major service thread a couple posts above.

Ernie kindly put me in touch with the source in California for the USI regulator that he used. Ernie felt this regulator was better, since it seemed to have 2 extra ground straps. Since my existing regulator also had these straps, I wanted to get the USI if I could, instead of the Regitar that might work but didn't have the straps.

The Calif Source said he used to work here in Phoenix, and put me in touch with Rick at Turbo and Electric here, and said he knew that they could also get the regulator for me. Rick at T&E looked into this for me, and I visited him yesterday. At first Rick thought that what they had in stock would work, but after seeing mine, Rick saw the extra 2 straps and said those were leads to a capacitor that's included with some regulators. Not sure what the function and how necessary it is to have the capacitor.

Rick was finally able to crossreference directly with Nippondenso and order one for me from them. This was all he could find. Nippondenso usually stocks these, but was out, but they're due in again next month. I ordered one... since I can wait with everything else I have to do to get my engine back in the car. The bad news is that the cost is $100. But I'd rather be safe and get the proper one, and not have to worry about my old original one failing.... now that I have the alternator apart!

I told Rick at T&D that others may want to contact him to also order these regulators. They mostly rebuild turbos and alternators/starters, etc. mostly for the large truck industry. They also can rebuild if you want. I'll post their contact info in my thread, or feel free to let me know if you'd like more info. They do have a website you can find via google. Not sure.. they may even be located in other cities. I'll post final result of my alternator rebuild in the thread on my major service. HTH...

 

Not sure Ernie... we'll see when I get it. But I did get the Regitar rectifier, which was less than $20, so I think I'm at $120 total plus tax and ship. I don't think the Unit 2 guy wanted to take the time with it, so passed me along to T&E here. I mentioned to Rick, perhaps he could contact Unit 2, but this was all he could come up with, after looking for 15min.

 

Hello 348 Brothers! I have some info to add on my previous posts in this thread about my alternator update, during my 348 major service.

I ordered the Regitar regulator that Ernie found, but after finding a local major supplier with Nippondenso sources (Turbo & Electric), I ordered an original replacement direct from Nippondenso for the original regulator. The Regitar doesn't have an extra capacitor on it (extra leads that Ernie mentioned), while the original does. After waiting over 4mo. with the regulator not showing up, I put the alternator back together with the Regitar. I'm sure it will work fine. I'll probably still check with T&D and may pick up the OEM if it ever shows up, as a spare. It is much more $ than the Regitar, though.

Also, I ran into the same wrong-sized belt problem that sspooner mentioned in this thread:

http://www.ferrarichat.com/forum/showthread.php?t=211000&highlight=348+alternator+belt

The new alternator belt I had came with the 348 major kit that I bought from Ricambi a year ago. As sspooner mentioned, mine was also too small!! It barely fit on, even without the tensioner installed! When I ordered the Ricambi kit, there were only 2 options offered.... Nippondenso and Delco, so I was not aware that Ricambi lists a larger Nippondenso belt for the "90A alternator". This belt is mentioned a couple posts above by GeorgeW.

At any rate, I decided to order the belt that worked for Sspooner in his thread, and it also worked perfectly for me! It was only $9.95 at Rockauto.com , which is the only easy place I could find it. It is listed, however, as a standard part in Dayco's belt lists. It's a Dayco Poly Cog #5050310. This belt is listed as a 770mm belt. Nice to also know that Ricambi has the 144909 770mm belt if the (apparently) normal Nippondenso belt doesn't work for you.

As a side note, I'm pretty sure that my car originally had a Delco and was upgraded. Not sure how that was normally handled, but when I removed my front timing chain cover, I found two driver's side studs that were about an inch or more too long. These both had an aluminum sleeve to make up this space for the nut, and I think the original Delco bracket fit over these longer studs. I've never seen one, though, so am not 100% sure. Can't see any other reason for the excessively long studs, though.

Best of luck with your alternator rebuilds!

 

Just a note for the DIY'ers

The tensioner adjustment bolt is NOT reversed thread. That is..TIGHTEN THE BOLT TO LOOSEN THE BELT....LOOSEN THE BOLT TO TIGHTEN THE BELT.

The issue I faced was not due to the lack of this information but I think its important to note.

My problem was caused by improper preparation of the bolts during the last service. No form of lubricant or corrosion resistance was applied to the fasteners prior to reassembly. Galvanic and general corrosion caused the tensioner cinch bolt to size. I rounded the *itch off trying to loosen it. Finally got it to go but the tensioner slider was (unknown to me) also siezed causing me to try using the tensioner adjuster as a jack. Guess who broke the friggen bracket. Luckily I'm in the business and know a few very capable welders.

Bracket fixed, reassembled with anti-sieze, and working good as new.

As an add on...I used a Denso #126000-1200 voltage regulator out of a Jaguar on the recommendation of a Denso engineer. Very similar (almost identical) operating characteristics. I've got the op charts to prove it. The original regulator Denso #126000-1500 is out of a 92-93 Toyota Camry but remains very difficult to locate and ridiculously expensive. By Toyota parts pricing, its cheaper to buy a new alternator than it is to buy the VR.


Lane

 

Thanks Ernie for all your research...wish I had this post last winter, but I can update it again this coming winter...

 

Per Ernie's Request to add this from my original thread:

pulled the alt, took it to the local autozone, and they said the both the rectifier and regulator tested bad. Not being an alternator wizard, I still wondered how they could both be bad at the same time, so decided to take it to a local alternator/starter rebuilder, that specialized in Nippondenso stuff... They never could get the numbers on the alt to match up with anything in their system or books... Imagine that... Turns out my "slip rings" had deteriorated and needed to be replaced, and the brushes were worn and also replaced. They also changed out the bearings. Grand total for the repair????

$107

slapped it back in the car, verified charging at 14.2-3 with the radio on, and am on my merry way.

I guess the main point in posting this is that something didn't feel right when I had it tested, showing both components to be bad, so I decided to let someone who knew what they were doing take care of it. POSSIBLY had I taken it apart I might have known/seen that the slip rings were bad, but I probably wouldn't have known about the brushes, and def wouldn't have known about the bearings. And I wouldn't have known how to repair the slip rings. I would have changed out the reg and rec, and still had a problem.

Sometimes it's better to not throw parts at something you know nothing about, especially when the local pros are cheap.

Thanks Ernie for the writeup, although I couldn't remove the belt like you did. I had to get the alt completely free before I had enough slack. 30-45 minutes to get it out, 15 to put it back in.


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#7 Yesterday, 10:41 PM
Saint Bastage
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Tom....You have a "harbor freight" near you. Couple of real cheap tools that are nice to have. A $10 dollar digtal multimeter will tell you everything you need to know about your electrical system. Not that in to electrics...They have a $2 dollar volt meter that plugs in to the cig lighter. Works great. differant color lights decide how well your alternator is working. Your repair price was nice and realistic. BZ to your alt shop, Good stuff.


Lane

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#8 Yesterday, 11:35 PM
ernie
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Quote:
Originally Posted by Tom_C
Imagine that... Turns out my "slip rings" had deteriorated and needed to be replaced, and the brushes were worn and also replaced. They also changed out the bearings. Grand total for the repair????

$107

Suweet!

And now we have something new to look for. The brushes are pretty easy to tell if they are worn because they don't stick out as far as new ones. But the slip rings are something I had no idea about. Great update and thanks for the informative post Tom. Learned something new.

How about adding this to the rebuild thread Tom? That way the rest of the boys will have a heads up on what else to look out for. So that you guys know what the slip rings are, they are in the center of the alternator, are made of copper in our alternators, and the brushes rub against them while the alternator is spinning.

See kids, every little thing helps us out. So no matter how small it is please share the info as it benefits us all in the long run.



Back to Tom: Something I forgot to add. I was looking at just switching out with the Acura alt mentioned earlier in the thread, and the pictures Autozone showed of it had a different plug, so I'm not sure it would have worked. Lane, I've got a good Fluke multimeter, just need to remember how to use it sometimes...

 

Thx for the great posts, Ernie. My alternator on my F355 just started to act up so the timing is perfect. I'm just a little hesitant to do the re-build myself as there may be slip ring and bearing problems as well. As Tom said, it might be prudent to look for a good alternator re-build shop.

 

Ernie, another concern of mine - would you recommend replacing the slip rings, bearings and brushes as well? Alternator has 40,000 miles on it. Problem I have is battery light comes on and flickers off at abt. 3-4,000 RPM. I agree with you that I would rather take it out than try to rebuild in place since space is so limited. Your comments are much appreciated.

 

If you're pulling the alternator out, it makes sense to replace as many parts as possible. For sure, the brushes, but if you have the time and inclination, might as well do the slip rings too. If the rear of your alternator is clean and relatively free from signs of oil / water ingress, then you may not need to replace them at all. As for the bearings, I can't imagine they'd need doing. Don't know if these were Koyo or NSK on those alternators, but either way, very robust.

To be honest though, if yourlight is flickering and going out at 3-4,000 rpm, have you checked the belt tension?

 

Ha Ha! At least then, you'd have no troubles overhauling the alternator next time it really has gone wrong!

I remember tearing my hair out on a problem with a car once and after replacing a lot of components to no avail, decided to swap out the engine. One of the last things I disconnected when about to remove the engine was a High Tension Ignition lead, which fell apart as I pulled it................ Needless to say, I proceeded with the engine swap regardless!

 

Ha Ha! I wish! Despite the job title, I never got my hands dirty as I had no idea what I was doing most of the time! There is no replacement for experience, so I think the FChat team have a good double act with us! I'm here all week............

 

Thank you for this great post. I followed the instructions and am back on the road for about $50.

One tip from my experience. Confirm which one of the NP alternators you have before ordering parts. The easiest way is to look at the cover when you pull it out. The smaller one requiring RN-04 does not have vents behind the outside screw and the larger one requiring RN-10 does.

I ordered RN-10 assuming I had the "newer" alternator because I have a 93. The part fit but then touched the cover and caused a short in the alternator. I then ordered the RN-04 and it was perfect. Would have saved some time and effort (and money on parts) if I would have checked to confirm which one I had.

Another option is just to order both. These parts are cheap enough considering the time and effort it takes to take out and replace the alternator when you do not have a lift. I almost spent more money on shipping, because of the second order, than I did on the actual parts.

Thanks again Ernie.

 

Well, I am finally lucky, I get to rebuild mine now. Is there a single source to buy the parts or did everyone have to go shopping around?