The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > 47 - Current classic GM Trucks > The 1988 - 1998 GMT400 Chevy & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 07-24-2011, 07:34 PM   #1
speedygonzales
Registered User
 
speedygonzales's Avatar
 
Join Date: Jan 2006
Location: Smithfield, VA
Posts: 1,501
L31 alternator upgrade

For those that want to upgrade from the 105 AMP alternator to either the 124 or 140 AMP model here's the information you need.

The short story is you need to move the water line to the heater core.
The new alternator has a different connector and the original belt is too short.

This post will help you get what you need.

Here is the connector you are dealing with on the original alternator.
original connector

You need to get either an adapter like this
adapter

or this pigtail
pigtail

this pigtail is available at Advance Auto as part number 85854 Dorman Conduct Tite brand. I spliced it into the original harness and left the original connector should I have to go back to it.

The 124 AMP and the 140 AMP alternator use the same connector that is different than the connector on the 105 AMP original alternator.

You also need to move the hard pipe water line behind the alternator since the new one is too large. Shown here
moved heater core line

The last thing is change the original belt which is 96.6 inches to one that is 97 inches long. The Dayco belt available at Advance Auto is part number 5060970. Gates also makes a micro V belt 97 inches long.
__________________
99 Z71 (98 body style)
Pride and joy
speedygonzales is offline   Reply With Quote
Old 07-24-2011, 08:02 PM   #2
jb1016
"Oh well, it's a driver."
 
jb1016's Avatar
 
Join Date: Jul 2008
Location: Nashville, TN
Posts: 3,467
Re: L31 alternator upgrade

Great info. This would be if you wanted to upgrade to a factory 124/140 amp alternator, right?
__________________
- JB - '93 C1500 SHORT/FLEET SILVERADO, 350/4L60E

Quote:
Originally Posted by Tom Petty
I don't know, but I've been told: You never slow down, you never grow old.
jb1016 is offline   Reply With Quote
Old 07-25-2011, 06:30 AM   #3
speedygonzales
Registered User
 
speedygonzales's Avatar
 
Join Date: Jan 2006
Location: Smithfield, VA
Posts: 1,501
Re: L31 alternator upgrade

No it doesn't make any difference who supplies the unit. Mine came from my aftermarket wholesaler.

All the stores I looked at while trying to find the pigtail, had the same setup. The 105's had the oval connector and the 124 and 140's had the rectangular connector.

Incidentally, the single wire going to the connector is on the terminal labeled "L". They are not in the same place on both of the connectors. The connectors on the alternators are labeled.
__________________
99 Z71 (98 body style)
Pride and joy
speedygonzales is offline   Reply With Quote
Old 07-25-2011, 04:39 PM   #4
speedygonzales
Registered User
 
speedygonzales's Avatar
 
Join Date: Jan 2006
Location: Smithfield, VA
Posts: 1,501
Lightbulb Now you can even clean CSFI injectors

For those with fuel injection, cleaning has always been necessary but difficult. If you have the spider injection system of the 4.3 or 5.7 Vortec. Up till now it's been impossible to do professional on the rail cleaning.

I had the old system of hose connected to pressurized cans of cleaner. You've seen the deal. Hook to fuel rails and disable the fuel pump. But that was only good for normal pressure systems below 40PSI like my LT1 camaro I used to have.

This would not work with the L31 and it's CSFI system. Since it requires 60 PSI.

Well boys the CSFI is not a problem any more. I got and used one of these just last week.



Seen on this page:
http://buy1.snapon.com/catalog/item....re&dir=catalog

You use shop air to dial in the pressure of the system you are cleaning and it even has it's own pressure gauge to check the system pressure before doing the cleaning.

The cleaner is somewhat hard to find since most auto parts stores don't carry it. At least none of the ones I checked, like Advance, Auto Zone, AutoValue, NAPA, Pepboys or O'Reilly's. You must use a cleaner that will burn. The type of cleaner you pour in the tank will NOT work.

Got some of this from my Snappy:
http://www.aecgroup.net/product/fluids-consumables/
Called Petrol fuel system cleaner.

Also got some of this from the Honda dealer:
http://www.bgprod.com/products/fuelair.html
Scroll down to product number 210. That same page also has the same type cleaner from BG.

For those that have tail pipe sniffers in their state. (I don't in Southern VA). This will help you pass emissions tests if you fail even after having done a complete tune up. (Assuming you don't have a dead cat).
__________________
99 Z71 (98 body style)
Pride and joy
speedygonzales is offline   Reply With Quote
Old 04-06-2012, 06:34 AM   #5
speedygonzales
Registered User
 
speedygonzales's Avatar
 
Join Date: Jan 2006
Location: Smithfield, VA
Posts: 1,501
For those that just need to know..I thought I would update the information

This is a CS130D style connector
CS130D connector


This is a CS130 style connector
CS130 connector
Which is the same connector used on CS144 style as well.
__________________
99 Z71 (98 body style)
Pride and joy
speedygonzales is offline   Reply With Quote
Old 04-10-2012, 06:54 AM   #6
jb1016
"Oh well, it's a driver."
 
jb1016's Avatar
 
Join Date: Jul 2008
Location: Nashville, TN
Posts: 3,467
Re: L31 alternator upgrade

Quote:
Originally Posted by speedygonzales View Post
The last thing is change the original belt which is 96.6 inches to one that is 97 inches long. The Dayco belt available at Advance Auto is part number 5060970. Gates also makes a micro V belt 97 inches long.
Speedy, I gotta question for you...I switched to a Powermaster 140-amp unit (PN57861) and ever since, if I turn my A/C compressor on, my serp belt tensioner rattles something awful. Do you think the longer belt would help?
__________________
- JB - '93 C1500 SHORT/FLEET SILVERADO, 350/4L60E

Quote:
Originally Posted by Tom Petty
I don't know, but I've been told: You never slow down, you never grow old.
jb1016 is offline   Reply With Quote
Old 04-10-2012, 03:59 PM   #7
speedygonzales
Registered User
 
speedygonzales's Avatar
 
Join Date: Jan 2006
Location: Smithfield, VA
Posts: 1,501
Re: L31 alternator upgrade

Length of the belt would only have an effect if it was so short it was causing the pulley of the tensioner to contact something it shouldn't. When I went to the 124 amp job, it was definitely taller. So I had no choice. The old belt wouldn't even fit. I noticed as I was putting it on, the tensioner pulley came down much lower than it was in the stock configuration.

I have found out through a friend with his own shop and my own experience that any time you change a belt, you should change the tensioner. They get jerky over time and it causes damage to the bearing in the alternator.

If you have forgotten the position of your tensioner pulley when it was stock take a look at another engine. I thought it was a good idea to get it as close to the original position as possible to keep the same amount of tension on it.

Since last year however, I have wiped out the bearings. However I got a cheap auto parts store alternator and am not sure if it's from tension or just cheap parts.

I ordered a power master from Summit http://www.summitracing.com/parts/PWM-38206/ and it's chrome too

That they price matched to $259. We'll see in a year how it holds up.

FWIW it's a 150 amp unit and it uses the same connector as our stock unit did.
__________________
99 Z71 (98 body style)
Pride and joy
speedygonzales is offline   Reply With Quote
Old 04-13-2012, 09:24 PM   #8
jb1016
"Oh well, it's a driver."
 
jb1016's Avatar
 
Join Date: Jul 2008
Location: Nashville, TN
Posts: 3,467
Re: L31 alternator upgrade

Yeah, my Powermaster uses the stock connector. I finally changed to Powermaster after repeatedly having bad luck with Tuff Stuff pieces. I had at least a couple of Tuff Stuff alternators that went bad on me, and then Summit sent me the wrong part like three times for warranty replacement. Somebody at Tuff Stuff (I think they're just dressed up Delco parts) had put a bunch of one-wire units into boxes with a three-wire part number, so I kept getting alternators that didn't have a connector at all. And then once, they sent me one that had to be reclocked. I seriously got five or six of those things before I told them to forget it and send me the Powermaster. It's worked great and I haven't looked back.
__________________
- JB - '93 C1500 SHORT/FLEET SILVERADO, 350/4L60E

Quote:
Originally Posted by Tom Petty
I don't know, but I've been told: You never slow down, you never grow old.
jb1016 is offline   Reply With Quote
Reply

Bookmarks

Tags
105 amp, 124 amp, 140 amp, l31 alternator

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 09:41 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com