An Image Of A Properly Designed High Amp Alternator

[MEXICOWANDERER]

• Note the 1/4" aluminum plate bolted onto the rear of this 7074 Ford 100 amp alternator
• The plate has 12 rectifiers (diodes)
• These are negative rectifiers
• Unseen within the case are 12 positive rectifiers. 24 total
• The original had six total rectifiers 3+3
• Notice the rear bearing. It has a nipple on the end to hold more grease
• Heads up performance versus a Nippondenso hairpin alternator leaves this one in the dust
• Yet the rectifiers in the Ford are light years more durable than those in the Nippondenso
• There are few "free lunches" in the alternator design dept
• I have redesigned and built more than two dozen special purpose alternators
• I am all too familiar with what can and cannot be done mechanically, electrically, and durbility-wise

[MEXICOWANDERER]

The hole is not threaded. It exists to have the brush retention pin pass through the case when assembling the alternator.

Some wise rebuilder may have thought to improve the level of security of the SRE bearing -- but any modifications performed are not the product of Delco Remy.

Delco remedied the issue upon incorporation of "improvements" with the CS-130-D which has a completely different housing and components.

[tempforce]

the cs-130's i installed, had covers over the end of the bearing. if you notice there is a hole, that is usually threaded for a metal screw. to hold the cover plate in place...

[ctilsie242]

Had multiple alternators in my first car, a Chevy... wondered why they kept popping every 20,000 miles. This makes perfect sense now.

[MEXICOWANDERER]

They were soooo stupid with the early CS-130 they glued a very fragile PLASTIC turbine fan onto the rear of the rotor. I chewed on the Delco CS project manager (Marion Hovermale) about it. The fan was changed to a simple stamped steel fin design which was cheaper and moved far more air. The exposed rear bearing was hidden in the soon to arrive CS-130-D model.

My bus Niehoff has exposed front and rear fans, and a cast iron frame. But both the regulator and rectifiers sucked so I fixed that.

It's these little quirky snatches of design insanity that reinforced by belief that I had made the right choice in not going corporate (and making 10 times the money). Design screwups are caused by in-house fiefdoms squabbling about incorporating signature designs that most of the time are ridiculously stupid. Hovermale emitted gagging noises on the telephone when I said those exact words to him.

[myredracer]

So what do you do for fun in your spare time, lol?

Interesting for tech types! Made me run out to my garage to look at the alternators on a couple of 60s era cars I'm working on. Neither have exposed shafts (whew) and both are well ventilated.

[MEXICOWANDERER]

# 1 STUPID DESIGN ERROR OF THE DELCO CS-130 ALTERNATOR

This is perhaps the pinnacle of stupid Delco alternator designs. Look at the image below. In the center is a completely exposed A6000xx ball bearing. Not only is the bearing exposed to the engine compartment, the bearing becomes -extremely- magnetic as the alternator charges. Tens of thousands of failures because this bearing gets contaminated, seizes, and blows the drive belt leaving the car stranded on the shoulder of the road.


PARTIAL SOLUTION for brand new alternators or replacements
Use a piece of high quality duct tape and tape a swatch over the bearing hole. Don't block any case ventilation holes.

[MEXICOWANDERER]

• The "field" is the rotor a bobbin full of coiled wire
• Some designs use three 3 amp diodes to supply power to the voltage regulator
• The three diodes only supply power when the stator is making power. Think "Automatic on/off switch
• The diode trio rectifies positive power the alternator negative rectifiers rectify diode trio negative power
• The ignition switch supplies power until the stator/diode trio powers the regulator

RECTIFIERS MUST BE DOWNGRADED WHEN THEY GET HOT

• Heatsink design is as much artform as it is science
• Several smaller rectifiers spread out over a large area distribute heat better than a giant rectifier in the center
• Because of the heat it is safe to use 300% of the total cold maximum output 100 amp alt 300 amps rectifier UNLESS the rectifiers are keep at a max of 80c by virtue of added heatsinking
• There are silicon and avalanche rectifiers used. Avalanche rectifiers act like zener diodes when reverse voltage approaches 28-32 volts
• Avalanche rectifiers give protection against transient voltage "spikes"
• A separate rectifier - a remote rectifier keeps the rectifiers cooler and does not add to the heat burden entering the alternator
• Dual internal rotor fans are used on late model alternators
• This is because the rotors have so much wire in the bobbin (ampere turns) little air can pass forward past the spinning rotor
• Remote mounting of a voltage regulator works fine if premium harness connectors are employed
• Gold plated and soldered Molex, connections are not part of the program for factory systems.

[theoldwizard1]

MEXICOWANDERER wrote:

• Note the 1/4" aluminum plate bolted onto the rear of this 7074 Ford 100 amp alternator
• The plate has 12 rectifiers (diodes)
• These are negative rectifiers
• Unseen within the case are 12 positive rectifiers. 24 total
• The original had six total rectifiers 3+3

So what is the logic behind all of the extra diodes ? Just to spread the electrical load across more diodes to reduce the current flowing through each diode and therefore reduce the heat created by each diode ?

I still do NOT understand the reason why some alternators have 3 "additional" diodes connected to the field.

[ROBERTSUNRUS]

🙂 Hi, Deleted.

[tempforce]

i used to use truck alternators on my vehicles in the 70's and 80's. that was before the automotive manufacturers got smart and started to install higher amp alternators.
Leece Nevill and delco remy

[GordonThree]

Looks good. Two of those bolted on to the Hemi and a 3000 watt psw inverter, I could run my trailer air while driving - no more climbing into an oven when stopping for the night.

[MEXICOWANDERER]

SOME GM DELCO ALTERNATOR PERFORMANCE CURVES

[MEXICOWANDERER]

It serves as an example. It is a 160 amp alternator.

Two shortcomings with the Ford 70-100 amp alternator series

• Very short brushes. Part of the brush holder
• Original has a 6203 front (DE) bearing -- inferior for heavy service
• OEM has gone to larger 6303 bearing on newer alts
• I do not know if unit shown has an upgraded drive end frame to use the 6303 bearing.

The two screws near the regulator plug _May Be_ for the brushes. The field connection. Insulated brushes can be connected to an A or to a B circuit voltage regulator.

The 5/16" bat bolt on the right looks like it is insulated, making it the + bolt. The one one the left looks like a chassis negative bolt being it's not insulated from the case.

When I was building these things, I had Saint Mary's Carbon build graphite copper brushes that were 5/32" longer than the originals. The absolute longest possible. The brush retaining pin slid across fully depressed brushes during assembly.

[MrWizard]

this for Marine use ?
maximum reliability ?