Alternator Amperage and Tach Not Working

[TurboDiverArt]

Hi All,

2 Questions:

1999 Suburban K2500 LT, power locks, windows, locks, heated seats with front and rear A/C and towing package. My alternator died lat week. Only getting like 10.5 volts when running and same at the alternator. Gonna replace this week. What amperage alternator would I have, 140amp? Is it marked on the alternator somewhere? Which ones are good? I’ve heard horror stories about the rebuilt ones from Advance and Pep Boys. Should I buy a new one from Rock Auto? If someone knows a good one, have a part number?

Second question. Maybe it just happened at the same time but my tach is not working. I hooked up my HD battery charger when the truck is running and I can get 14 volts and the charging idiot light goes out but the tach still does not work? Is there a fuse for the tach? The other gauges all appear to be working.

[DaveNY]

Your tach runs off of alternator,the pully dia is critical in tach accuracy. Which is why I suggest a reputable rebuilder in your area is the best bet.You get your correct alt back. Dave

[DmaxMaverick]

Go HERE (http://www.alternatorparts.com) for any alternator need you have. I done a lot of business with this store, and it can't be beat anywhere. NEW alternators, made in USA, higher quality, higher performance, longer service life (dual bridge models), fast shipping, and they fit out of the box. All at less money than a rebuilt of unknown origin. If you buy from him (really, it's just one guy who answers his own phone), be sure to include make/model, pulley size (measured at outer edge of groove surface, not the the valley of the groove), and number of wires in the connector (important, most parts stores get this wrong, like the pulley). Give him a call and he'll tell you which one to order online, or if you insist, he'll take the order over the phone (online is better, you'll get order and shipping info via email, vs. waiting for the invoice in the box).

Your original is probably a 105 amp, CS-130D. He offers a larger CS-144 alternator that outperforms anything I've seen you can get from any other place. They work as advertised and bolt in place without any modification. An added bonus is the idle output. Your original will will typically put out less than 50% of rated amperage at idle. The high performance CS-144 will put out your original's maximum high speed amperage, at idle (about 100). These things just flat work. I recommend the dual rectifier bridge model. They last a lot longer (greater heat management) and respond much quicker than singles (fewer power dips).

I have no affiliation or association with this business, and I only endorse what works.

If, for any reason, the pulley you get is different than your original (regardless of where you get it), just swap the pulley. Loosen/tighten the nut with the alternator in place on the engine and belt on, with an impact wrench.

[TurboDiverArt]

Your tach runs off of alternator,the pully dia is critical in tach accuracy. Which is why I suggest a reputable rebuilder in your area is the best bet.You get your correct alt back. Dave
Didn't know the tach runs off the alternator. So if the alternator isn't working internally it won't produce a tach signal? Didn't know that.

[DmaxMaverick]

Correct. A flaky tach is usually the first indicator the alternator is heading south. This is also why the pulley size is critical. The wrong size pulley makes the tach inaccurate.

[DennisG01]

I just made a bookmark of that link, for future reference!

I'll just add my experience. A year ago, I had a similar situation. I was all ready to buy a new alternator and then I double checked the connections (battery and alternator). Turns out the connection at the alt was loose. If you haven't already, double check the tightness and the condition of the wire that goes from the battery to the alternator.

[DaveNY]

DMAX, Thanks for the Alt site stuck it in favorites.
Dave

[THEFERMANATOR]

Your original is probably a 105 amp, CS-130D. He offers a larger CS-144 alternator that outperforms anything I've seen you can get from any other place. They work as advertised and bolt in place without any modification. An added bonus is the idle output. Your original will will typically put out less than 50% of rated amperage at idle. The high performance CS-144 will put out your original's maximum high speed amperage, at idle (about 100). These things just flat work. I recommend the dual rectifier bridge model. They last a lot longer (greater heat management) and respond much quicker than singles (fewer power dips).

Having done this swap in the past, the CS-144 is not a direct swap for a CS-130D as teh voltage regulator plugs are diffewrrent and either require the powermaster adapter or plug replacement. The output stud is teh same size and they do use the same mounting design. The AD-244(4 prong regulator version, 00-04) IS a direct swap for the CS-130D and the AD-230(the CS-130D's MUCH improved replacement), and puts out just as good as teh CS-144 as it utilizes the same rotor size which is what gives the 144MM case alternators there good idle output. And for those in a pinch, the 2001 DURAMAX 130 amp alternator is a AD-244 that will directly bolt onto the 96+ 6.5 trucks and plug in directly as well as swaps directly over to the 96+ gas engines as well. You will need a 1 size longer belt though most likely for a diesel application, and maybe 2 sizes longer for a gasser due to the pulley being slightly larger than a gassers. And the REMY brand one I bought from ADVANCE was an all new alternator that came with the correct sized diesel pulley on it for the 6.5 tach.

[DmaxMaverick]

Having done this swap in the past, the CS-144 is not a direct swap for a CS-130D as teh voltage regulator plugs are diffewrrent and either require the powermaster adapter or plug replacement. The output stud is teh same size and they do use the same mounting design. The AD-244(4 prong regulator version, 00-04) IS a direct swap for the CS-130D and the AD-230(the CS-130D's MUCH improved replacement), and puts out just as good as teh CS-144 as it utilizes the same rotor size which is what gives the 144MM case alternators there good idle output. And for those in a pinch, the 2001 DURAMAX 130 amp alternator is a AD-244 that will directly bolt onto the 96+ 6.5 trucks and plug in directly as well as swaps directly over to the 96+ gas engines as well. You will need a 1 size longer belt though most likely for a diesel application, and maybe 2 sizes longer for a gasser due to the pulley being slightly larger than a gassers. And the REMY brand one I bought from ADVANCE was an all new alternator that came with the correct sized diesel pulley on it for the 6.5 tach.

This is not correct. Any of the available alternators are available with any number of connectors. The platform is used for dozens of OEM's, and each may have several different applications for the same alternator, and/or different alternators for the same application. This is why any good distributor will require the connector info to ensure the correct application. I've done several replacements and upgrades from the distributor I mentioned, and he got it right the first time, every time. If you get the wrong pulley, you bought the wrong alternator for the application, or didn't specify. The first recommendation in a catalog is not always the correct one. Chain stores are notorious for this. I recommended the pulley swap only as an easier option, compared to a return. The cost of a new pulley from a local source will likely be less than return shipping for an entire alternator, and the one you have in your hand is already paid for, and takes away no time to order or go get one.

[THEFERMANATOR]

This is not correct. Any of the available alternators are available with any number of connectors. The platform is used for dozens of OEM's, and each may have several different applications for the same alternator, and/or different alternators for the same application. This is why any good distributor will require the connector info to ensure the correct application. I've done several replacements and upgrades from the distributor I mentioned, and he got it right the first time, every time. If you get the wrong pulley, you bought the wrong alternator for the application, or didn't specify. The first recommendation in a catalog is not always the correct one. Chain stores are notorious for this. I recommended the pulley swap only as an easier option, compared to a return. The cost of a new pulley from a local source will likely be less than return shipping for an entire alternator, and the one you have in your hand is already paid for, and takes away no time to order or go get one.


The CS-130 and CS-144 both use the same plug, and the CS-130D is a differrent plug. I've never seen a CS-144 with anything but the old CS style plug in that had the one large pin and 3 smaller ones whereas the CS-130D, AD230, and AD244 all use the flat 4 style plug.

The adapter is here on the site you linked to, straight from them(1995-present vehicles that currently have the CS-130D or AD-230 alternators must use the D1-W1206 adapter
).
http://www.alternatorparts.com/CS-144_Special_offer.htm

[DmaxMaverick]

The CS-130 and CS-144 both use the same plug, and the CS-130D is a differrent plug. I've never seen a CS-144 with anything but the old CS style plug in that had the one large pin and 3 smaller ones whereas the CS-130D, AD230, and AD244 all use the flat 4 style plug.

The adapter is here on the site you linked to, straight from them(1995-present vehicles that currently have the CS-130D or AD-230 alternators must use the D1-W1206 adapter
).
http://www.alternatorparts.com/CS-144_Special_offer.htm


We aren't talking about the CS-130. I never mentioned it. The 130 and 130D are completely different animals, and not interchangeable without the use if an adapter. The vehicle of discussion is a 1999 model, and was never equipped with a CS-130. The CS-130D, as well as the 144 and, 230 and 244, can be equipped with any number of connectors. These are used by dozens of OEM's, in many different applications, not only by GM. The link you posted is not one I would have visited to order an alternator for a 1999 GM truck. Try THIS PAGE (http://www.alternatorparts.com/cs130-cs130d-series-alternators.htm).

[THEFERMANATOR]

We aren't talking about the CS-130. I never mentioned it. The 130 and 130D are completely different animals, and not interchangeable without the use if an adapter. The vehicle of discussion is a 1999 model, and was never equipped with a CS-130. The CS-130D, as well as the 144 and, 230 and 244, can be equipped with any number of connectors. These are used by dozens of OEM's, in many different applications, not only by GM. The link you posted is not one I would have visited to order an alternator for a 1999 GM truck. Try THIS PAGE (http://www.alternatorparts.com/cs130-cs130d-series-alternators.htm).

Last post on this from me. The CORRECT upgraded alternator for a 96+ 6.5 truck origanally equipped with a 105 amp CS130D is a AD244 for high output. The CS144 WILL require an adapter to use on a truck that had a CS-130D stock, plain and simple as I can put it. If you don't believe me even your alternator link states the same. ALL cs130 and 144's use the same regulator plug which is the older 86-95 style plug. 6.5 trucks from 96-00 that got the 124 or 140 amp alternators did have the CS144 alternator. There are 2 different alternator plugs for 6.5's built from 96+. 105 amp units use the CS-130D, and the 124/140 amps were the CS144. If you have a 105 amp unit and want more output, install an AD244 for an 01 DURAMAX truck as it is a drop in swap with the correct pully, correct plug, and same mounting hook-ups, the CS144 WILL require an adapter or a new plug if you origanally had a CS-130D.

And if you go to your link and read through it, it even states down in the harness portion of the upgrade section teh adapter is required for 95+ trucks which origanally had a CS-130D. I'm VERY familiar with this swap as I did some of teh first write ups on it way back, and have done teh CS-130D upgrade on my BURB as it only had the 105 amp.

http://www.alternatorparts.com/ad_alternator_order_page.htm

[DmaxMaverick]

Your information is incomplete. The CS-144 does not require an adapter, if you get the correct alternator. Same with the 130D. They are interchangeable if space allows. I have a 144 on my 2001, with NO adapter (upgraded from a 130D). I'll post pics of both, side by side, if a thousand words isn't enough. I've done a bunch of upgrades, and have had to use adapters before, depending on the source alternator. There are more alternator configurations than you are aware of. I was in the same boat 7-8 years ago, and used adapters. The only time you should need an adapter, if you source the correct alternator, is retrofitting a post-96 with a pre-94 (CS-130 upgrade to D or later). 94-96 is a gray area, which could have had either connector. Been there. Done that. Continue installing adapters if you insist, but it isn't necessary. Order the alternator you want, with the correct connector. That simple.

The bottom line is, there is absolutely a bolt-on replacement or upgrade for any 94+ GM truck, without the need for any adapters, mechanical or electrical. The only exception being physical space if you have aftermarket stuff getting in the way.

The last link you posted doesn't specifically apply to 1999 trucks. Still, not necessary when you can replace with the correct series without the need for an adapter, or possibly, a remote rectifier. There are many options available, and you can "fit" any alternator into any vehicle, if you wish. The price goes up, the parts count increases, and the end result is no better. Why complicate it?