6066 (1960-1966) GMC Truck Club Bitcoin now accepted here! 
Pay Dues
Pay Dues or become a Site Supporter
 



Go Back   6066 (1960-1966) GMC Truck Club > 6066 GMC Truck Club Forum > GMC V6 and V12 Engines


GMC V6 and V12 Engines Engine repair and rebuilding

Reply
 
Thread Tools
  #1  
Old October 2nd, 2016, 03:59 PM
kchampagne's Avatar
kchampagne kchampagne is offline
Senior Member
 
Join Date: Feb 2016
Location: Littleton, Colorado
Truck: 1965 GMC Suburban 4x4
Posts: 181
Rep Power: 97
kchampagne is on a distinguished road
Default Tiiming Chain Replacement

Hey all, I am working on my "spare" 305 and putting together a list of parts I need, including the timing chain. The chain is extremely loose. The engine was rebuilt and has approx. 15,000 miles since. Anyone know what causes the chain to loosen on low mileage? Maybe the chain wasn't replaced during rebuild. Also, the camshaft sprocket moves (slides on camshaft about 1/8") Based on my maintenance manual, there isn't a spacer or thrust plate behind the sprocket (boneheads probably left them out). Does anyone have a picture of the thrust plate and camshaft sprocket spacer? Not sure if I can fabricate one up. Better yet, anyone have spares laying around I could buy? I would bet they do sell these anymore.

Thanks much!
Reply With Quote
  #2  
Old October 2nd, 2016, 05:50 PM
HOTRODJOHN HOTRODJOHN is offline
Senior Member
 
Join Date: Apr 2014
Location: Henderson, Nevada
Truck: 1964 GMC PICKUP, 1956 PONTIAC SAFARI, 1949 CADDY SEDANETTE
Age: 75
Posts: 179
Rep Power: 106
HOTRODJOHN is on a distinguished road
Default Re: Tiiming Chain Replacement

I can get you a photo tomorrow when I go to the shop. I just changed my motors chain and 2 sprockets. The only piece behind the lower gear is a large splash washer. How is the key way. I had a regular chain and gear but I changed it over to 2 sprocket type gears and double roller chain. I will get you the picture and the part numbers and post them tomorrow night. It should be posted after 7PM EST because I am on the West coast. John
Reply With Quote
  #3  
Old October 2nd, 2016, 07:48 PM
kchampagne's Avatar
kchampagne kchampagne is offline
Senior Member
 
Join Date: Feb 2016
Location: Littleton, Colorado
Truck: 1965 GMC Suburban 4x4
Posts: 181
Rep Power: 97
kchampagne is on a distinguished road
Default Re: Tiiming Chain Replacement

Awesome John! No hurries. It is the camshaft sprocket that moves. My manual indicates a thrust plate and spacer are supposed to be behind it? Mine is the double roller also. Where did you buy your replacement?

Thank you!
Reply With Quote
  #4  
Old October 2nd, 2016, 08:11 PM
HOTRODJOHN HOTRODJOHN is offline
Senior Member
 
Join Date: Apr 2014
Location: Henderson, Nevada
Truck: 1964 GMC PICKUP, 1956 PONTIAC SAFARI, 1949 CADDY SEDANETTE
Age: 75
Posts: 179
Rep Power: 106
HOTRODJOHN is on a distinguished road
Default Re: Tiiming Chain Replacement

I decided to go to the shop and take the picture. You can see that there are not any spacers on there the splash washer (not sure of the technical term) is in front of the gear. I believe I bought the gears from Auto Zone. The part #'s are all Cloyes Chain #C-166, Cam Gear # S310 and Crank Gear # S-311.
Hope this helps. John

PHONE PHOTOS 10-2-2016 012.jpg
Reply With Quote
  #5  
Old October 3rd, 2016, 03:07 AM
kchampagne's Avatar
kchampagne kchampagne is offline
Senior Member
 
Join Date: Feb 2016
Location: Littleton, Colorado
Truck: 1965 GMC Suburban 4x4
Posts: 181
Rep Power: 97
kchampagne is on a distinguished road
Default Re: Tiiming Chain Replacement

Thank you John! That is the same setup I have on my crank sprocket, so that is good. Do you know if you had a spacer or washer behind the cam sprocket?

Thanks much!
Ken
Reply With Quote
  #6  
Old October 3rd, 2016, 03:39 AM
TJ's GMC's Avatar
TJ's GMC TJ's GMC is offline
Senior Member
 
Join Date: Mar 2015
Location: Cave Junction, Oregon
Truck: 1964 GMC 1500 LWB Wideside 305E V6.
Posts: 1,341
Rep Power: 399
TJ's GMC is on a distinguished road
Default Re: Tiiming Chain Replacement

You can get a timing chain kit that comes with the sprockets and gears from O'riellys. Nothing behind the cam gear that I recall. You will be surprised that a new chain really isn't much tighter.
Attached Images
File Type: jpg 003.JPG (1.53 MB, Multiple views, 7 clicks)
__________________
"Excuse the rust I use my truck"
1964 GMC 1500 305E/sm420 4 barrel intake mod and dual exhaust.
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

1964 Chevy C20 292/SM420
1966 Chevy C10 292 hotrod 6/TKO600


My youtube channel aka Military Chevy:
To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
Reply With Quote
  #7  
Old October 3rd, 2016, 03:53 AM
HOTRODJOHN HOTRODJOHN is offline
Senior Member
 
Join Date: Apr 2014
Location: Henderson, Nevada
Truck: 1964 GMC PICKUP, 1956 PONTIAC SAFARI, 1949 CADDY SEDANETTE
Age: 75
Posts: 179
Rep Power: 106
HOTRODJOHN is on a distinguished road
Default Re: Tiiming Chain Replacement

There are no spacers behind the cam gear. Let us know how you make out. John
Reply With Quote
  #8  
Old October 3rd, 2016, 02:22 PM
turbobill turbobill is offline
Member
 
Join Date: Feb 2013
Location: northern NY when not flying
Truck: 1968 HM80 with a 478M and a few engines plus a Toro-Flow
Posts: 98
Rep Power: 94
turbobill is on a distinguished road
Default Re: Tiiming Chain Replacement

Timing chains (all types) will slacken within a few thousand miles. It's the nature of the beast. I usually advance a cam 2 to 4 degrees to compensate.
Reply With Quote
  #9  
Old October 3rd, 2016, 10:19 PM
James James is offline
-= Extreme Supporter =-
 
Join Date: Jun 2013
Location: Greer, SC
Truck: 1964 GMC 1500 2wd
Age: 69
Posts: 432
Rep Power: 199
James will become famous soon enoughJames will become famous soon enoughJames will become famous soon enough
Default Re: Tiiming Chain Replacement

Quote:
Originally Posted by HOTRODJOHN View Post
I decided to go to the shop and take the picture. You can see that there are not any spacers on there the splash washer (not sure of the technical term) is in front of the gear. I believe I bought the gears from Auto Zone. The part #'s are all Cloyes Chain #C-166, Cam Gear # S310 and Crank Gear # S-311.
Hope this helps. John

Attachment 5463
That is an oil slinger on the crankshaft. It help the crankshaft seal keep the oil inside the engine.
Reply With Quote
  #10  
Old October 4th, 2016, 12:31 AM
HOTRODJOHN HOTRODJOHN is offline
Senior Member
 
Join Date: Apr 2014
Location: Henderson, Nevada
Truck: 1964 GMC PICKUP, 1956 PONTIAC SAFARI, 1949 CADDY SEDANETTE
Age: 75
Posts: 179
Rep Power: 106
HOTRODJOHN is on a distinguished road
Default Re: Tiiming Chain Replacement

KC, there are no spacers behind the Cam gear. John
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


Similar Threads
Thread Thread Starter Forum Replies Last Post
Timing chain set HOTRODJOHN GMC V6 and V12 Engines 23 August 17th, 2016 06:35 AM
timing gears & chain Archiver Previous Forum Posts 1 August 14th, 2011 01:27 AM
Timing Chain Archiver Previous Forum Posts 4 March 11th, 2011 02:22 AM
Gear or Chain? Archiver Previous Forum Posts 0 November 18th, 2004 04:56 AM
timing chain Archiver Previous Forum Posts 0 July 1st, 2003 03:48 AM


All times are GMT +1. The time now is 10:33 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2013, Jelsoft Enterprises Ltd 481713359920|1712309594|0