Go Back   Chevrolet Forum - Chevy Enthusiasts Forums > Brand Review > Engine Building & Overhauling
Sign in using an external account
Register Forgot Password?
Search

Engine Building & Overhauling All you ever wanted to know about building and rebuilding engines in here! Remember to post your model-specific questions in the correct section.


Reply
 
 
 
 
LinkBack Thread Tools
  #1  
Old 08-23-2006, 01:16 AM
 
Join Date: Aug 2006
Posts: 4
Default Timing Chain Alignment in 5.7L

Hey I have what should be a simple question about a 1982 Corvette.

On a 350 Cubic Inch (5.7L) V8, timing chain sprockets be aligned?
Each sprocket (one on the crankshaft, one on the camshaft) has a small mark on it.
Most service manuals show the camshaft mark at the bottom 6 o'clock, and the crankshaft mark at the top 12 o'clock.
So that the two points are very close together and point at each other.

HOWEVER, the 1982 GM Service Manual has a diagram and it points the camshaft mark at the top.
So that the marks on both sprockets are at 12 o'clock.

The GM manual is the only book I've seen that has it positioned like that.

Does anyone know which is correct?
Register today for free or log-in if already registered to remove this ad!
Reply With Quote
  #2  
Old 08-23-2006, 01:56 AM
 
Join Date: Jul 2006
Location:
Posts: 504
Default RE: Timing Chain Alignment in 5.7L

Any that I have seen regardless of make or model have been dots together. When you took it apart were they together? If I remeber right in your other post you had not touched the timing chain yet, right? And it did run where it was, right? If so then if they were together or close that is how they would go. It is also the factory engine too, right?, just modified to a card setup with the computer out/disconnected? You might be able to ask a dealer or even go to a local shop and see what their books say. If I had to guess I would say together, but you don't want to run it to far off as you can destroy valves and pistons.
__________________
Reply With Quote
  #3  
Old 08-23-2006, 02:42 AM
 
Join Date: Aug 2006
Posts: 4
Default RE: Timing Chain Alignment in 5.7L

Well I am replacing the timing chain because the old timing chain slipped.

It slipped was pretty much half way between 6 o'clock and 12 o'clock.

Since i didn't see it until after it slipped, i'm not sure where it is supposed to be.

Thanks
Reply With Quote
  #4  
Old 08-23-2006, 10:57 PM
 
Join Date: Jul 2006
Location:
Posts: 504
Default RE: Timing Chain Alignment in 5.7L

That does make it a bit harder. That would keep it from running. If you don't have it on yet I have one more question/suggetion. I know some if not all of the 80's Chevys had a type of plastic gear (just the teeth) on the cam shaft, if you have that it is more than likely pretty worn down if not stripped and it slipped on that. If so if you look at the way your engine turns you can tell which way it went, but how far is a better question. I just thought of that. If it made more that a 1/2 rotation on a slipped gear that wouldn't help. You may want to turn your engine by hand and see if you hear anything that dosen't sound right or feel right. If it slipped to much you could have a bent valve.
__________________
Reply With Quote
  #5  
Old 08-25-2006, 11:00 AM
 
Join Date: Jul 2006
Posts: 2
Default RE: Timing Chain Alignment in 5.7L

Hang on a moment here... we're talking about a small block chevy engine right???
The crankshaft sprocket has half as many teeth as the camshaft sprocket, right???
The crankshaft spins 2 times for every time the camshaft spins
Doesn't that mean that the crankshaft sprocket will be in the 12 o'clock position at the same time the camshaft is in the 12 and the 6????
That clears you from doing any mechanical damage to the pistons and valves (basic engine timing)
So for nobody has mentioned ignition timing which would be the real question here...
last time i installed a distributer I had to turn the engine over by hand to see when the intake valve closed... next TDC is whereI would start to install the Dist
I could have looked to see the marks on the chain but The front cover was on
Reply With Quote
  #6  
Old 08-25-2006, 07:46 PM
 
Join Date: Jul 2006
Location:
Posts: 504
Default RE: Timing Chain Alignment in 5.7L

I'm sorry I was thinking to hard. Your right.
__________________
Reply With Quote
Old 08-25-2006, 07:46 PM
 
 
 
Reply

Tags
350, 57, alignment, chain, chevy, engine, explained, general, install, jpeg, marker, motors, tdc, timing, v8


Thread Tools

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 On
Trackbacks are On
Pingbacks are On
Refbacks are On


Join Chevroletforum
Advertising

Featured Sponsors
Vendor Directory
Our Sponsors
All times are GMT -5. The time now is 01:49 AM.

Internet Brands, Inc.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO ©2010, Crawlability, Inc.

Emails Backup