Author |
Message |
guy dagenais Samba Member
Joined: October 21, 2005 Posts: 154 Location: Montreal
|
Posted: Wed Dec 05, 2018 12:54 pm Post subject: Problem with timing 30 degrees before TDC |
|
|
Hi
Posting this for a friend. We have just installed a refreshed 1700cc engine in 73 Westfalia. Points are well ajusted, valves also, everything new but can't get the engine to run right at the specified 10 degrees after TDC. Will only work when timing set at 30-35 degress before TDC. What are we doing wrong?
Guy
73 Westy |
|
Back to top |
|
|
airschooled Air-Schooled
Joined: April 04, 2012 Posts: 12727 Location: on a bike ride somewhere
|
Posted: Wed Dec 05, 2018 1:06 pm Post subject: Re: Problem with timing 30 degrees before TDC |
|
|
Hi Gus,
Make sure you clarify the conditions under which you're setting the timing.
10°ATDC is only at idle with the factory dual carbs installed and everything functioning like new. Do you have these carbs?
28-30° BTDC is how we get time engines to get us very close, and stay in a safe range to avoid over-advance damage. We do this by removing all distributor vacuum hoses, and revving the engine until the timing stops advancing. This will be somewhere between 3,000 and 4,000 RPM, (aka, loud!)
Tell us about how you're setting your timing?
Robbie _________________ Learn how your vintage VW works. And why it doesn't!
One-on-one tech help for your Volkswagen:
www.airschooled.com |
|
Back to top |
|
|
guy dagenais Samba Member
Joined: October 21, 2005 Posts: 154 Location: Montreal
|
Posted: Wed Dec 05, 2018 1:35 pm Post subject: Re: Problem with timing 30 degrees before TDC |
|
|
Hi
The dual carbs were replaced by a single 2 barrel carb. Besides that everything is the sane |
|
Back to top |
|
|
babysnakes Samba Member
Joined: August 19, 2008 Posts: 7107
|
Posted: Wed Dec 05, 2018 1:54 pm Post subject: Re: Problem with timing 30 degrees before TDC |
|
|
guy dagenais wrote: |
Hi
The dual carbs were replaced by a single 2 barrel carb. Besides that everything is the sane |
What model distributor are you using? |
|
Back to top |
|
|
WESTYJACK Samba Member
Joined: February 21, 2017 Posts: 266 Location: LAVAL,QC CANADA
|
Posted: Wed Dec 05, 2018 2:05 pm Post subject: Re: Problem with timing 30 degrees before TDC |
|
|
Salut Guy
Mon bay est a 28-30 btdc at 3200 rpm
moteur 1800cc 1975 FI _________________ VW bus type 2 1978 transplant engine 1975 1800cc fuel injection |
|
Back to top |
|
|
Wildthings Samba Member
Joined: March 13, 2005 Posts: 50352
|
Posted: Wed Dec 05, 2018 3:23 pm Post subject: Re: Problem with timing 30 degrees before TDC |
|
|
The factory spec will not work with a center mount progressive carb. You need to leave the retard side of the can disconnected at ALL TIMES and then as said above remove the vacuum advance hose and time the engine to 28° BTDC at 3500+ rpm. Just keep your face away from the belts and rev it until you don't see the timing advancing any more with your timing light. After you have the mechanical timing correct reconnect the vacuum advance hose and verify that the vacuum advance comes in as you open the throttle a bit.
I run 28° BTDC in the summer and advance the timing to 32° for the winter which makes the engine run smoother when cold. |
|
Back to top |
|
|
guy dagenais Samba Member
Joined: October 21, 2005 Posts: 154 Location: Montreal
|
Posted: Wed Dec 05, 2018 3:42 pm Post subject: Re: Problem with timing 30 degrees before TDC |
|
|
Thanks everyone for your help, we will check this tomorrow morning.
Much appreciated!
Guy |
|
Back to top |
|
|
Spike0180 Samba Member
Joined: June 06, 2015 Posts: 2269 Location: Detroit, Michigan
|
Posted: Thu Dec 06, 2018 8:43 am Post subject: Re: Problem with timing 30 degrees before TDC |
|
|
This might help.
https://www.thesamba.com/vw/forum/viewtopic.php?t=217070&highlight=progressive _________________ Brutis Patches Izabich: 1970 VW Transporter - 1776cc DP
Current State: Projects never truly end...
Location: Grosse Pointe, Michigan
Other cars: 2003 F150, 2003 Jetta GLI vr6-6sp
Sambastic: adj; the quality of being nit picky, elitist, expecting everyone to do things the way they believe is best with no regard to situation, "sambastic" |
|
Back to top |
|
|
|