73-87chevytrucks.com

73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: Jerr-conn on October 16, 2017, 05:55:40 pm

Title: 87 350 tbi 700r04 timing question
Post by: Jerr-conn on October 16, 2017, 05:55:40 pm

I want to check the initial timing on my 87 350 tbi.  I have read there is a tan/black stripe wire
Near th brake booster that needs to be unplugged before ck' ing timing. I have looked all over
Mine and have only  found a tan/ white stripe wire that can be unplugged. Did GM change the
Color code for 87 or do I have to look harder? This wire is located in the area where a clutch
Pedal would be.

Title: Re: 87 350 tbi 700r04 timing question
Post by: bd on October 16, 2017, 06:41:28 pm

Look again.  The EST bypass connector on V8 applications breaks out of the engine compartment harness a few inches away from the firewall bulkhead connector just to the left of the brake vacuum booster.  It is a single wire Weatherpack connector. 

Title: Re: 87 350 tbi 700r04 timing question
Post by: Smitty31 on October 17, 2017, 02:39:24 pm

I know on some models it's under the carpet on the passenger side. Also if you have a vaccum advance you won't have this wire. Just simply unplug the hose and plug. Then set or check timing

Title: Re: 87 350 tbi 700r04 timing question
Post by: Jerr-conn on October 22, 2017, 03:47:23 pm

Found the EST wire. Disconnected it re-set timing. Could not spin tires before, but it sure lights
Them up now. Timing was so retarded. Set it at 2 degrees BTDC. Happy now , except it's almost
Time to put it away for the winter.