Express, Savana & G-Series Vans Offered in both a full size van, or a large box truck, the Express is the modern GM workhorse.

Chevrolet Express
Platform: GMT Van

Need advice on how to check timing

Thread Tools
 
Search this Thread
 
Old Mar 30, 2019 | 7:26 PM
  #1  
johnt365's Avatar
Thread Starter
CF Junior Member
5 Year Member
Liked
 
Joined: Mar 2019
Posts: 54
Likes: 3
Default Need advice on how to check timing

Hi all,

I'm a long time Chevy fan and recently bought a 95 GMC g2500 with a 350 to take some road trips with the family. My other Chevy is a 74 Corvette that I have restored and rebuilt. I mention this because even though I am comfortable around an engine, this van is a different animal.

I know the procedure for checking and adjusting ignition timing. I am hoping for some guidance from the van community on how to point the light at the tab!

I am hoping there is a trick to it or a magical tool that will let you check it without having to pull the shroud off etc. Everything is just a little bit tricky on a van it seems.

Thank you for any help
.

Best regards,
John
Reply
Old Mar 31, 2019 | 10:11 AM
  #2  
tech2's Avatar
Super Moderator
 
Joined: Mar 2011
Posts: 9,175
Likes: 521
Default

distributor are b4 my time but I remember my instructor setting his using a vacuum gauge; he could not see the timing marks.

turn the distributor until you achieve max vac...back it off 2" of vac and he was done.
Reply
Old Mar 31, 2019 | 12:28 PM
  #3  
mountainmanjoe's Avatar
Super Moderator
 
Joined: Feb 2017
Posts: 6,207
Likes: 689
Default

You can also hook up a scan tool and read the Cam Retard Offset.
Reply
Old Mar 31, 2019 | 1:53 PM
  #4  
johnt365's Avatar
Thread Starter
CF Junior Member
5 Year Member
Liked
 
Joined: Mar 2019
Posts: 54
Likes: 3
Default

Thanks for the suggestions.

I think this 95 is going to be a challenge. The sticker says to set the timing to 0* which makes me think the computer is controlling the advance. And, this thing is OBD1 so it wont let me hook up my scan tool.

I gotta think about this one.

Thanks again
Reply
Old Mar 31, 2019 | 3:20 PM
  #5  
kevinkpk's Avatar
CF Monarch
10 Year Member
Liked
 
Joined: Jul 2011
Posts: 5,920
Likes: 140
From: kevinkpk
Default

You can set the advance with a vacuum gauge. I prefer a timing light. Piece of chalk on the balancer, mark the line, and set it with the light, and timing tab.
Reply
Old Mar 31, 2019 | 3:37 PM
  #6  
johnt365's Avatar
Thread Starter
CF Junior Member
5 Year Member
Liked
 
Joined: Mar 2019
Posts: 54
Likes: 3
Default

How are you guys using a light? The tab is completely hidden and under the power steering.

Are you removing the shroud and fan? Even then looks like you’d need a mirror.
Reply
Old Mar 31, 2019 | 7:03 PM
  #7  
kevinkpk's Avatar
CF Monarch
10 Year Member
Liked
 
Joined: Jul 2011
Posts: 5,920
Likes: 140
From: kevinkpk
Default

Use a vacuum gauge.
Reply
Old Mar 31, 2019 | 7:43 PM
  #8  
oilcanhenry's Avatar
CF Monarch
 
Joined: Oct 2017
Posts: 4,605
Likes: 269
From: USA
Default

Originally Posted by kevinkpk
You can set the advance with a vacuum gauge. I prefer a timing light. Piece of chalk on the balancer, mark the line, and set it with the light, and timing tab.
Yeah, that's how I always did it too. Man, I am no fan of vans. Everything is a pain in the *** to do with those vehicles. Never owned one in my life, but I've worked on them.
Reply
Old Mar 31, 2019 | 7:49 PM
  #9  
oilcanhenry's Avatar
CF Monarch
 
Joined: Oct 2017
Posts: 4,605
Likes: 269
From: USA
Default

Originally Posted by kevinkpk
Use a vacuum gauge.
Back in the day I saw guys time the engine by keeping the distributor hold down bolt loose enough to turn by hand hard. Then they would hit the road with it until the motor knocked. Then they would back it off until no knocking was heard, then tighten the dist. bolt down to spec. Those were the days!
Reply
Old Jun 1, 2019 | 9:32 PM
  #10  
johnt365's Avatar
Thread Starter
CF Junior Member
5 Year Member
Liked
 
Joined: Mar 2019
Posts: 54
Likes: 3
Default

Finally got a chance to set the timing and wanted to report back.

So a 95 wants to be set at zero. To do that:

1. I recommend getting some white paint on a toothpick or something and get under the van and mark your timing line on the balancer.
Just makes it easier to see.
2. remove dog house and disconnect the advance connector. Its a brown wire with black stripe found in the wiring harness by the distributor.
3. remove the washer fluid reservoir. Key step.

Now when you shoot your light down you can juuuust barely position your head and the light so you can make out the tab. The make your adjustment to get to 0.

Hope this helps someone someday.

John
Reply



All times are GMT -5. The time now is 7:28 AM.