timing adjustment

[gold84gmc]

does anyone know if there is supposed to be a tab on the harmonic balancer for the timing?...and if there is where on it is it supposed to be?...because i tried looking for one on my truck and i couldnt find one....i have an 84 gmc with a 350

[frogman68]

The balancer should have a groove (from say the timing cover to the pulley)across it that will line up with the tab on the timing chain cover

[dumbucket1]

does your truck still have a timing tab? I have came across many with them missing. It would be on the timing cover either directly below the water pump or to the right near the power steering pump.

[BlueCollarRon]

you most likely have a shiny chrome plate with the tabs missing, like mine.... (82 gmc 350)

Unless you buy a bolt on timing plate, you have to check timing with a vaccum gauge.

[78 Chevyrado]

Here's a pic of what you should have  that tab at 2 oclock over the balancer.  If you don't have it you need to buy a bolt on tab


Here's an aftermarket bolt on tab:

[gold84gmc]

how do you check the timing with a vacuum gauge?

[frogman68]

how do you check the timing with a vacuum gauge?

Hook up the vacuum gage adjust the dizzy until you get the highest reading. Not sure if I would do it this way timing lights are cheap. Check your sticker under the hood to see what it should be set to. Not sure on your year if it has the ESC that (if it is still hooked up) you will have to disconnect that.