MJHSC400

Basically, concerning the quality of the electrical connection, I torqued it well, and all contacts are clean-- Again, I don't see any need for it-- I doubt it would make more than .01% difference in current capacity if that much-- I do however think that it will help maintain the quality of the connection over time when exposed to the elements-- IE: 100,000 miles later-- By then I'll have a 1JZ or a 1.5JZ under the hood or a blue 96 911 Carerra-- either way it won't matter much....

All I know is my battery charges now and I can jam my system for 6 hours with a 1000w monoblock and a 350w Class A amp on my mids and highs and my battery is still nice and hot..

Much better than it was before, as it wouldn't even start the next day after driving it for 20 minutes--

The original brushes still had enough material that I really didn't have to change them either-- about 35% of them was used up, so they had plenty of life left--

I'm more worried about my p/s pump honestly-- It's kinda weak at low rpm's after that last fluid change--

JohnEd

iTrader: (1)

Matt,

My slip rings were worn thru badly. My brushes were like new. My rebuilder said that my condition was especially comman with brushes that had gotten oil on them. He said that after being oil soaked they become like little cutting tools.

Nothing speaks like success and I think you have that.

You are right about the grease preventing the contact from deteriorating and also about the decrease in ohms being small at original assembly. Switches tend to spark and the grease adds lots of life to the switch if it was designed to use it. I know of a few people a, at least, that have shared with me that they rinced all the "goo" out with contact cleaner.

John

MJHSC400

Ohhhh, I got it backwards, the BRUSHES cut the SLIP RINGS- sorry--

As far as every little technical aspect apparently I missed that one, but hell it works awesome and cost me $65-- how can I complain-- I have OE quality instead of some super cheaply built reman--

MJHSC400

SpinAll4-- Thanks for pointing out my "stupid" mistake--

Maybe you should focus on fixing that broken window of yours -- It could rain--

VJZ

iTrader: (3)

I can't figure out how to order the rectifier from the link you provided. I can get the bearings and brushes from a parts store in town.

MJHSC400

You Can call the guy and he'll set you up with everything you need-- I called him and he stocked all the necessary rebuild parts for the Denso Alt..

Michael56

iTrader: (1)

You said that the regulator is not known for failure, but I'm wondering if there is any way to check it (with the alternator apart) with a multi-tester.

I finally found a Auto Electric shop here in NorCal willing to sell me the Bridge Rectifier, as I did the Continuity checks on the Diodes to confirm they are toast.

All these other guys want you to just bring it in, and charge you $150 to fix it.

Also-- a quick question on the failure root cause.

when I took the battery-end "positive" connection apart, I noticed that the vertical threaded post on the Lead post clamp-- that the cable ends attach to -- had a arcing-erosion point on it about halfway down. The arcing had eroded the threads down to the root in a location about 1/8" in size.

This time, I'm cleaned everything with scotch brite pads, and a battery post brush. And I'm going to use the dielectric grease on all surfaces when I put it all back together.

I'm just wondering if that arcing point is what killed the Diodes. I had just put a used Alternator that checked out fine on a tester -- on the Car 2 months ago--and then it too failed.

Any comments appreciated.

Michael
East Bay of NorCal

88Legend

I am having alternator problems as well. I put in new brushes, voltage regulator and put in a used rectifier that tested ok and my car does not charge at all. The red ominous battery light came on and I at least got the car home.

Should I replace the whole rectifier with a new one and see what that does?

xspsi6

iTrader: (31)

The link is dead for the Bridge Rectifier to be ordered so id there any other place to order from?

I know this is an old thread but it's a shot in the dark that somebody may know

MJHSC400

All I know is nationsautoelectric.com is still in business and I just rebuilt my wife's es300's alt with parts from them in the past few months with good results.

I have actually been doing quite a bit of work to that car lately, mostly preventative though...

xspsi6

iTrader: (31)

Ok I got the Inr733p hd rectifier bridge from them on order today only to find out my Slip rings are worn through

NaturalJZ

iTrader: (1)

Do the sc300 and sc400 have same alternator? (94 sc300)

Arkansas

Think ill just upgrade to the more powerful alternator....id just mess up rebuilding mine

xspsi6

iTrader: (31)

It's beyond easy

PERRYinLA

Whether you rebuild the alternator yourself or buy a remanufactured one, ensure that the gray silicone rubber brush cover is in place.
Below is a photo of what it looks like. When I bought a remanufactured alternator, this piece was missing. Without this cover the brushes and slip rings are exposed and once dirt gets in there, the grinding begins.
Since you probably don't want to disassemble a rebuilt alternator in the auto parts store to check for this cover, just remove it from your core alternator before you turn it in.
And if you don't have one on your existing alternator, that's a tip-off you have a (not-thoroughly) rebuilt alternator.

Also, I don't agree that the best way to remove the alternator is through the bottom, in fact every time I have removed my alternator it has been from the top. Maybe if you use a jack and just lift one side of your car, the sway bar twists/swings out of the way to allow you to remove it from the bottom. But if you use ramps like I do, the stock SC400 sway bar continues to sit right in the middle of that opening at the bottom of the car. So, on my car at least, there's just no way the alternator is coming out of the bottom with that sway bar in the way (unless maybe you remove the power steering rack!).

It's tight, and you may have to rotate the heavy alternator to find the right orientation for it to squeeze through, but it comes out through the top as long as you remove the coolant overflow tank and the belt tensioner pulley. You might also have to move or compress the large radiator hose to make enough room.

And finally, if you're lucky enough to have a power steering pump that doesn't leak (my car has had 3 so far and they all eventually leaked, some more than others) then you need not read any further. But for those of us that aren't that lucky you know that the leaking power steering fluid at the very least makes a mess of the alternator and at the very worse can short it out and ruin it prematurely. And if you don't have that brush cover I mentioned, the fluid gets into the brushes, attracting dirt and grinding down the slip rings.

So what I did the last time I removed my alternator was fabricate a little splash shield to keep the power steering fluid from dripping directly onto the alternator. It's made of thin, flexible metal about 6 inches by 7 inches with holes punched in 3 of the 4 corners. I secured it right underneath the power steering pump with some flexible wire. The front of the shield is slightly higher than the rear so that any fluid that drips onto it drains towards the rear of the engine beyond the position of the alternator. You can see it in the photo below, taken while looking upwards into the engine compartment with the alternator removed- the shield almost completely hides the PS pump above it..

Obviously this does not stop the leak, it merely channels the leaking fluid to a part of the engine compartment where it does less harm and helps keep the alternator cleaner.