How do you set the timing on a 1990 Chevy silverado with a stock 350?

Answer 1

Answer

If you have removed the distributor you need to place number one piston on it's compression stroke and then drop the distributor on number spot on the distributor. You then need to find to advance wire for the distributor and disconnect it. It should be a light brown and black wire that can be found on the firewall or behind glove box close to the computer. After you disconnect the wire you can time the vehicle to the timing mark on the sticker under the hood.

You do NOT have to set number one piston on the compression stroke (top dead center). This is ONLY required if you removed the distributor and accidentally turned the engine over, hit the ignition key or turned by hand. If you are replacing the dist. just mark the rotors contact point, best place is on the firewall. When you pull the distributor the rotor will turn counter clock wise, try and remember the place, also, look at the cap hold down screw and try to remember it's location. That will make it easier to get the initial timing. If it does not drop in where it was pointing when it was removed, lift it up an turn one tooth (counter clockwise one tooth at a time) to get to the proper point. Not as hard as it sounds. Everything else in the original answer is correct. Now if the distributor was removed and the engine was turned over then you will have to find #1 on the compression stroke. Timing is 4 degrees BTC, although I put it at 6 degrees. After it is set tighten down the distributor hold down bolt. DON'T forget the round distributor gasket, even if you have to buy one or you will have a oil leak. Don't forget to plug the tan/black stripe wire back in after timing is set. This is true for GM TKs from 1988(some '87's) to 1995.