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sooxies

Another Rectifier/Diodes Failure

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Finally got around to disassembling my old alternator.  I believe this is the factory original one.  Unfortunately I stripped out 2 of the 4 screw heads holding the diodes in! :doh:  Any tips for stripped screws? :thumb1:

 

Anyways, 

 

@Mopar1973Man  The diodes you sell...do they fit in all Denso alternators found on 94-02 trucks?  I have a 98.5, which from the looks of it, is the same as a 12 valve alternator.  It doesn't have that plug on the back (see photo from FSM).  

IMG_5470.JPG

alternator_photo.JPG

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Just now, Mopar1973Man said:

Got you covered...

 

Most certainly. Thank You!

 

I found it interesting that mine burned up right at the beginning of summer.  Also this vehicle lived in California (Los Angeles suburb) all of it's life prior to my ownership.  One wouldn't think the grid heaters were used very often.  It does have a block heater too...oddly enough.       

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48 minutes ago, sooxies said:

Also this vehicle lived in California (Los Angeles suburb) all of it's life prior to my ownership.  One wouldn't think the grid heaters were used very often.  It does have a block heater too...oddly enough.       

My truck was bought and has stayed in San Diego County, except for trips.  The grid heaters come on during the cold mornings here and it also has a block heater which I've never used.  

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$71.45

http://www.fostertruck.com/diode-pack-rectifier-bridge-for-dodge-denso-alternator.html

 

Vs.

 

$54.50

https://mopar1973man.com/store/product/61-denso-alternator-rectifierdiodes/

 

Nations alternator is a full replacement alternator which will require the ground wire mod to basically omit the old charge lead and route to the passenger battery. Be aware it can be quite a bit more than even a remanufactured Denso.

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Would anyone happen to have the bridge with the stud NOT on a 90 degree exit ?

 

I recently purchased mine from fostertrucks (larry b) and recieved the one pictured...mine has a straight exit stud, not the 90 like shown.

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You must not have a Denso alternator, but a Bosch. But i dont know that for sure.

Edited by dripley

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Bosch alternators are not easy to rebuild from what I understand you have to unsolder each diode one at a time and replace them. Where the Denso alternator is a package like what you see above. 

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I dont see any numbers on the housing, i removed it to rebuild (have bridge, bearing and brushes)...but the bridge stud exits at a 90 like pictured. 

 

Mine exits straight...i was under the impression the the bosch was totally different.

 

Every thing i have looks identical, mounts the same and fits accordingly...minus stud exit direction.

 

My battery termianl cable bolts tonthe side of the housing with the factory cover included...not the rear of the housing like this bridge would suggest.

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15 hours ago, Stormin08 said:

I dont see any numbers on the housing, i removed it to rebuild (have bridge, bearing and brushes)...but the bridge stud exits at a 90 like pictured. 

 

Mine exits straight...i was under the impression the the bosch was totally different.

 

Every thing i have looks identical, mounts the same and fits accordingly...minus stud exit direction.

 

My battery termianl cable bolts tonthe side of the housing with the factory cover included...not the rear of the housing like this bridge would suggest.

It doesn't sound quite right. Perhaps your Denso is off of a different car or truck. You might do better to go get the correct Denso for our trucks and keep the rebuild parts for the future.

 

I don't know if there is a part number on the alternator.... I'm curious to find out if its for a different vehicle.

 

BTW, The W-T grounding mods are worth every effort in reducing damaging levels of A/C ripple even with a new or old alternator.

Edited by JAG1
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https://www.oreillyauto.com/shop/b/charging---starting-16772/alternator-11425/f7cab2ae3cc0/2002/dodge/ram-2500?q=Alternator

 

Just as a reference photo...if this link works, you can see 2 different exits...

1 would appear to have the bridge in this article (which i bought)...the other has the exit point like mine (which would exit straight from the ring if the bridge).

 

Mine is not a 90 degree exit.

 

All i can see is sticker residue, i grabbed the parts to have on hand. Ac ripple has always been very low, but recently had some gremlins with DTC...my tuner failed and is now removed, and the various dtc's have not returned in a qeeks driving.

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Perhaps yours is a rebuild that got modified during rebuild.

 

 I knew the ND alternators are better than Bosch from years ago experience with my first gen truck. So I changed over to ND on my 2002 even though the Bosch was still charging fine. I'm glad I did anyway.

 

I need to order another diode bridge from 'Mopies' (Mopar1973Man) again just to have on hand

Edited by JAG1

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https://www.oreillyauto.com/shop/b/charging---starting-16772/alternator-11425/f7cab2ae3cc0/2002/dodge/ram-2500?q=Alternator

 

Using this as a reference, the top photo shows the 90 exit, and claims to be bosch rebuild...

The lower is a straight exit, and claims ND rebuild.

 

So, does every one here have the 90 exit bridge ? Mine has the tin rear cover and all in tact...

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Well, maybe it is a model year thing.

 

I will verify my build date, and see from here 

 

When search for bridegs...i get a bunch od this bridge fits XYZ series alternators....but i cant locate my numbers, and didnt think to write them down when i did try to rebuild it. I just reinstalled everything and went.

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My build date was mid 2001 IIRC. I bought it in October of 2001.

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So what else, specifically, in an alternator can cause excessive AC noise.  I just replaced the diodes and brushes in my original and I'm getting the same exact reading as I was with a new replacement?  Literally, the exact same reading on my Fluke 87.  Cold engine, everything off, .068 at startup (clearly too high), and then it slowly works it's way down.  New alternator was a cheap unit which I returned immediately after doing a noise test then decided to do a rebuild of my own. 

 

The only real issue I am having is I notice the tachometer is not moving in a fluid motion. Speed/RPM dependent?  I really might make a video of this issue because it's quite interesting.  Revving the engine in neutral it appears to be fine.  Accelerating in first/second gear it seems to move normally.  Getting into third, and cruising gears, it's obvious that it looks like a ticking motion.  Not like a wall clock, but you can tell it's not as smooth as it should be.  When using cruise control at freeway speeds it's the most obvious because you can rest your foot on the pedal and feel it adjusting up/down constantly (matching with the tach).            

 

I would assume the cluster is fine if it's only doing it under certain circumstances.  I've sometimes noticed, at idle, the tach bounces ever so slightly as well.  I did recheck my valve lash to rule out an issue there.  I read that some members had funky issues with valves not being adjusted properly.                         

 

Still to do:

 

1)  Ground Wire Mod

2)  Pull 140A fuse and disconnect alternator for a test drive to see if issue goes away          

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2 hours ago, Mopar1973Man said:

Weak batteries or grid heaters running. Go drive the truck charge you batteries and test again. Make sure all accessories are turned off.

Grid heaters have been unhooked to preserve diodes and @BBHD no codes with cluster test...sorry fellas forgot to mention that.  Knew I forgot something in my original post.  

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The tach needle bouncing is very common at idle. Mine always has for the most part. But smooth there after. The ground wire mod should help. It decreased mine by 65%.

Edited by dripley
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I've also load tested both of my batteries and they still show 98% even being 5 years old.  I religiously keep them on a float charger if I knowingly am not going to drive the vehicle (vacation, etc.) 

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I don't know if this will help, both my second gens had bad cruise control vacuum hoses. Particularly the two short pieces (about 1 1/2'' long) nearest the top of the firewall.... they are connected to what looks like a small black/white flapper valve.

 

Edited by JAG1
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