I have a 5VZ with a supercharger that I just purchased a 270 AM DC power alternator.

Its actually a 91 Toyota pickup with the swap (I figured this was the place to post it because its much more a 1st gen taco question).

In one wrenching session I installed a URD 2.2 pulley, and the alternator.

The alternator was MUCH larger than the previous Denso one and I was very limited with how much space I had for it. I had to essentially pull the mount for the alternator and the bracket, and then get it in and then bolt it all in.

I did a big 3 upgrade and have a direct line with 1/0 cable to the positive battery post, and even took and ran 1/0 cable to the frame as a ground.

When I turned everything on I noticed several things, my truck was registering a lower low voltage from the tachometer. I have an in line 300amp fuse from the cable that goes to the positive terminal and it has a voltage meter that read 12.5 before starting the vehicle, and then 11.8- 11.7 once the vehicle was running.

I rand the vehicle for about 30 minutes and nothing is flickering, all the lights are working, which makes me believe that the alternator is actually working, but just at a lower voltage.

Additionally, I notice a rattling noise from somewhere around my crank shaft (which is a URD crank shaft thats been installed for about 6 months.

It would click intermittently and then it would go away. and then come back at idle.

Its about 20 degrees out if that makes a difference.


I was under the impression that the dynamic tensioner on the TRD supercharger properly gives you the right tension, but now I just read from gadget that possibly this is not the case?

Is there a world where the belt is slipping because it is too loose, thus giving me a lower charge?




WHAT I DID.

I pulled the alternator/supercharger belt off and started the vehicle for about 10 seconds and the licking had gone (the power steering belt was still on so the water pump, and crank shaft, and power steering pulley were running.

This makes me think its not a bearing in one of these unless for some reason the added or lack of tension from the other belt is coming into play?

I'm at a loss at this point. I have a very good ground, and the big 3 done quite carefully. I also left the original alternator cable in the back as I was instructed from multiple forums.


What could the clicking be, and is there a world where the belt being too loose even though the dynamic tensioner is there is not giving it enough tension?

Thanks all. This is my first post and I have been reading for years. Sorry if this shoudl actually go in the 3rd gen pickup portion, I just think its more of a 1st gen question. Also my swap was done by toy only swaps and I've had zero problems and the timing belt was changed etc (6 months ago). All of this happened when I changed the pulley and alternator. Is there a specific alternator from DC for superchargers and I didnt know it? I was under the impression it didnt matter since the denso one is the same.

Thanks,

Logan

 

Here is a video of the rattle noise!

 

I can't speak to your noise, but it is a certainty that if the voltage is less at the battery when the engine is running than it is when the truck is not running,
it is a virtual certainty that the alternator is not charging the battery.
If you have a strong battery, it might run the truck, even with headlights on for several hours.
Eventually though, the battery will completely discharge.
I would expect that the battery should show around 13.6 volts, or better, with the engine running.

 

little update. I ended up checking the power on all three prongs and was getting 12v from each one with the key on. I also checked my grounds etc. This led me to believe that the alternator was either dead (which I was skeptical of because of its price and it being brand new and I had bench tested it before putting it in). I removed the adapter in the back and discovered that one of the prongs was ever so slightly bend. After using a small pick I re aligned it and plugged it in, and am getting 14.3 ish now so it appears to be working!

Whats more, the sound is gone for now. I'm going to double check with a test drive in better weather tomorrow, but what I'm most curious about is how the sound could go away once the alternator is working...

Regardless if it keeps working I just want to know why this could have been the case?