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 1967 - 1972 Chevrolet & GMC Pickups Message Board

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 01-08-2010, 08:40 PM   #1
mike16
Registered User
 
Join Date: Dec 2009
Location: bisbee, arizona
Posts: 1,529
factory alternator pully for 72 307

restoring my 1972 chevy c 10's engine compartment and I noticed that my lower alternator bracket has some bogus spacers between the bracket and the head. actually they were nuts installed between the bracket and the head so that the alternator pully lined up. clearly this is wrong. but looking at some pictures of other engin compartments I see similar "accomodations". either spacers between the bracket and the head or some sort of spacer rig between the bracket and the alternator.

I have an alternator that has a single groove pully that is almost 3/8 inch thicker than every other one I've seen. the thicker portion is between the pulley groove and the alternator fan. Pictures to follow.

what everybody doing regarding this?

my engine compartment is to remain origional

anybody got pictures of thier al pulley?

Last edited by mike16; 01-09-2010 at 01:02 AM. Reason: she's a 72 not a 73 duh!
mike16 is offline   Reply With Quote
Old 01-09-2010, 12:53 AM   #2
mike16
Registered User
 
Join Date: Dec 2009
Location: bisbee, arizona
Posts: 1,529
Re: factory alternator pully for 72 307

sorry its a 72

Last edited by mike16; 01-09-2010 at 01:03 AM.
mike16 is offline   Reply With Quote
Old 01-09-2010, 06:42 AM   #3
JimKshortstep4x4
Senior Member
 
Join Date: Jul 2001
Location: Muskegon,MI,USA
Posts: 6,026
Re: factory alternator pully for 73 307

Here is a picture but it is not a close up. Usually the pulley alignment problems are caused by mismatching drive or water pump pulleys. With the alternator being the easy fix it is shimmed to match as in your case. From your description, the correct pulley would make your problem worse.

Jim
Attached Images
 
__________________
1971 Shortbox step side 4x4, 350 sbc, 3:07 rear end
1965 Impala SS 400 sbc, Muncie rock crusher
1966 Impala SS 396 bbc, TH 400
1969 El Camino, 350 sbc, TH 350
1971 Snowplow built on a Blazer frame
1972 GMC Short bed, stepside, TH 400, 427 BBC

Last edited by JimKshortstep4x4; 01-09-2010 at 06:45 AM. Reason: Changed picture
JimKshortstep4x4 is offline   Reply With Quote
Old 01-09-2010, 11:40 AM   #4
mrein3
Registered User
 
mrein3's Avatar
 
Join Date: Feb 2000
Location: Center City, MN, USA
Posts: 3,253
Re: factory alternator pully for 73 307

Quote:
Originally Posted by JimKshortstep4x4 View Post
Here is a picture but it is not a close up. Usually the pulley alignment problems are caused by mismatching drive or water pump pulleys. With the alternator being the easy fix it is shimmed to match as in your case. From your description, the correct pulley would make your problem worse.

Jim
I agree with Jim on this one. I had all kinds of issues with my alternator not lining up with my drive and waterpump pulleys. I tried all my fixes on the alternator. Then one day I got smart and purchased a set of pulleys off a known unmolested truck. All my problems went away.

Jump over to the parts board and look for a matching set of crank and wp pulleys and remove all washers, bolts, and shims from the alt. bracket and mount it to the head like it was intended.
__________________
'70 cab, '71 chassis, 383, TH350, NP205.
'71 Malibu convertible
'72 Malibu hard top
Center City, MN
mrein3 is offline   Reply With Quote
Old 01-09-2010, 05:09 PM   #5
mike16
Registered User
 
Join Date: Dec 2009
Location: bisbee, arizona
Posts: 1,529
Re: factory alternator pully for 73 307

to bad I cant import pictures. they were worth showing:whine

what the pictures would have shown is that one pulley is about 3/8th inch thicker than the other and larger in diameter as well. the thicker pulley places the belt in perfect alignment with my water pump and crqnk pulley. and no home spun spacers are needed.

a survey of local and internet vendors indicate they only sell the thinner pulley alternators

has any body run into this problem?

Last edited by mike16; 01-09-2010 at 06:37 PM.
mike16 is offline   Reply With Quote
Old 01-09-2010, 08:54 PM   #6
mike16
Registered User
 
Join Date: Dec 2009
Location: bisbee, arizona
Posts: 1,529
Re: factory alternator pully for 73 307

installed.
mike16 is offline   Reply With Quote
Old 01-10-2010, 02:48 AM   #7
roger0080
Registered User
 
Join Date: Nov 2000
Location: Carver County, Minnesota, USA
Posts: 626
Re: factory alternator pully for 73 307

I replaced my original 350 motor with the plain jane GM crate motor.
The heads on it are about 1/4" shorter on the front then the original.
I had to put spacer blocks behind the alternator bracket and the head, which I detest doing, but have to in order for the pulleys to line up.

I think you have the pulley I need! Any idea where to get one?

Jim, I've always liked that blue/white color combo you have there, that is going to be one really nice truck when done. wow.
__________________
72 Chev C-10 90% restored (former AZ truck) ...
71 Chev K-20 Cheyenne my vacation crusier...
72 Chev C-10 Now retired and striped after many faithful miles...
72 GMC 1500 Retired to the junk yard after bought new in '71...
roger0080 is offline   Reply With Quote
Old 01-10-2010, 02:06 PM   #8
br161
Registered User
 
br161's Avatar
 
Join Date: Aug 2008
Location: goldsboro nc
Posts: 62
Re: factory alternator pully for 73 307

not sure if this helps
Attached Images
  
br161 is offline   Reply With Quote
Reply

Bookmarks


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 08:26 PM.


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