Electrical Article - Denso Alternator retrofit for diode

[Bcoan55]

Denso Alternator Modification 

 

I'm doing this write-up in case anyone runs into the problem I did and they don't want to buy a new or find another style alternator. After I bought the diode replacement and tried to install it I realized that it was slightly different from mine. Note: The new lead is smaller in diameter and shorter than the old lead.

 

Here is a link on how to take the alternator apart written by IBMobile. If yours is like mine and the lead comes off the side the B+ post nut sizes will be a 13mm but the steps will be the same.

 

 

Tools required for modification:

* Small cut off wheel or Air saw

* Ball-peen hammer

* Small files

* Drill and bits

 

Hardwear required:

Two M6-1.0 nuts

 

 

 The original diode pack has the lead coming off the side sticking through 2 tabs. 

 

 The new diode lead sits on top of one of the stud.

 

Take a small cut off wheel or air saw and cut roughly where the sharpie mark is. 

 

I cut a little too much off but this is what it should look like. 

 

Drill 2 holes left of the letter B for the lead to stick through. Then use a small file to make the hole bigger. 

 

Once you can see the small U shape around the bottom of the Lead where the insulator sits, take a ball-peen hammer and bend down the metal around it so it sits flat. Youll need to trim the hole big enough that the back of the original lead insulator fits through it. 

 

Now you need to take the old lead insulator and cut out a piece for the cable to sit lower on the lead. You'll need to do this on the same side but opposite end of the flat part of the U shape. You'll also need to take a 7/16 drill bit and drill a little of the center out so the first nut you screw on can sit further down and the cable lead can sit flush on top of the nut and plastic insulator. 

 

Put everything back together and install the Alternator. Put the insulator on and tighten the first nut down. This will hold the insulator in place. Next, install the cable lead and next nut. The cable should stick out of the notch you cut. Since the diode lead is shorter there won't be much of the threads sticking out after the 2nd nut is put on.  

 

 

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