Notices

Where is 8* BTDC??

Thread Tools
 
Old 07-08-2016, 07:11 AM
  #1  
Registered
Thread Starter
 
Join Date: Sep 2014
Posts: 11
Likes: 0
Received 1 Like on 1 Post
Default Where is 8* BTDC??

I've exhausted my search options on all of the interwebs. I'm setting base timing on my Merc 350 MAG MPI. Its a 0L372*** era motor, year 1999. I found a million threads on how and have the service manual. I though I completely understood how to do this procedure until I went to do it. My issue is that I see my mark on the balancer and see the mark on the plastic timing cover, but doesn't this indicate TDC #1? Shouldn't there be a larger tab on the timing cover to indicate degrees BTDC and ATDC? I looked at google images and could find nothing. The timing cover is just a small "V" shaped notch. The balancer does not appear to have any other markings unless I'm missing them. Please help.
RMassa187 is offline  
Old 07-08-2016, 07:44 AM
  #2  
SB
Registered
iTrader: (1)
 
Join Date: Nov 2004
Location: On A Dirt Floor
Posts: 13,562
Received 3,132 Likes on 1,409 Posts
Default

To make sure, what does your distributor cap / rotor look like ?

#1)


or #2)
SB is offline  
Old 07-08-2016, 07:48 AM
  #3  
Platinum Member
Platinum Member
iTrader: (6)
 
F-2 Speedy's Avatar
 
Join Date: May 2012
Location: Midwest & T-Rock
Posts: 10,436
Received 3,079 Likes on 1,364 Posts
Default

from TDC on the balancer ( should be a line 0 ) there should be small dash lines before and after TDC, if for go back four notches before the TDC line, that is 8* before, each dash line is 2*,
Attached Thumbnails Where is 8* BTDC??-balancer-cj-timing-marks.jpg  

Last edited by F-2 Speedy; 07-08-2016 at 07:51 AM.
F-2 Speedy is offline  
Old 07-08-2016, 07:59 AM
  #4  
Registered
 
Join Date: May 2012
Posts: 1,465
Received 9 Likes on 7 Posts
Default

You can use a timing light with an advance knob, or if you don't have one or any marks, 8 degrees before would be about 9/16" to the right of the top dead center mark on the balancer (for an 8 inch balancer).
Mr Maine is offline  
Old 07-08-2016, 08:05 AM
  #5  
Charter Member #1171
Charter Member
 
obnoxus's Avatar
 
Join Date: Feb 2001
Location: Clearwater, FL
Posts: 4,019
Received 21 Likes on 16 Posts
Default

Originally Posted by Mr Maine
You can use a timing light with an advance knob, or if you don't have one or any marks, 8 degrees before would be about 9/16" to the right of the top dead center mark on the balancer (for an 8 inch balancer).
Thats the easiest way,,,,, but there should be another timing mark on the balancer as well
__________________
I want to live in a world where a chicken can cross the road and not have its motives questioned.

Last edited by obnoxus; 07-08-2016 at 08:13 AM.
obnoxus is offline  
Old 07-08-2016, 08:43 AM
  #6  
Registered
iTrader: (1)
 
donzi matt's Avatar
 
Join Date: Jul 2003
Location: Moultonborough NH
Posts: 1,339
Received 7 Likes on 5 Posts
Default

On some of the Vortec motors, there is not. There is a notch in the balancer for TDC, and a mark on the plastic timing cover, and that is it. I use an advance light and set the ECM to timing set mode with a scan tool to set these motors.
donzi matt is offline  
Old 07-08-2016, 08:52 AM
  #7  
Registered
iTrader: (1)
 
Join Date: Jun 2011
Location: Henderson, KY
Posts: 2,167
Received 82 Likes on 58 Posts
Default

When I've run in to that (on cars), I just use my adjustable timing light to determine degrees (on the light, not the tab).

Doh - looks like I was late to the party.

Last edited by ALL_IN!; 07-08-2016 at 08:54 AM. Reason: late response
ALL_IN! is offline  
Old 07-08-2016, 12:20 PM
  #8  
Registered
 
Join Date: Mar 2009
Location: OFallon,Mo.
Posts: 1,758
Likes: 0
Received 3 Likes on 2 Posts
Default

Buy ya a timing tape. Their available at most auto parts stores. Make sure you get one for the correct diameter balancer. http://www.jegs.com/p/Mr-Gasket/Mr-G...46079/10002/-1
picklenjim is offline  
Old 07-08-2016, 02:35 PM
  #9  
Registered
Thread Starter
 
Join Date: Sep 2014
Posts: 11
Likes: 0
Received 1 Like on 1 Post
Default

SB, my distributor is picture number 1. It does require that base timing be set for this model. My balancer does not appear to have any hatch marks. I am putting the ECM (MEFI 3) into base timing mode by jumping pins A And B at the diag connector. I don't have an advance timing light. I guess I'll pick up some balancer timing tape. Thanks for the all the advice. This is what I was missing. Funny that so many other threads here and forums ask how to set base timing but nobody asked this question.
RMassa187 is offline  
Old 07-09-2016, 07:25 AM
  #10  
Registered
 
Join Date: Apr 2013
Posts: 105
Likes: 0
Received 0 Likes on 0 Posts
Default

hey guys i have the same problem except i have distributor in picture #2
tazdevil is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.