Okay, I've been through some other threads, but I just want to make sure I understand. To set the timing on my California '87 pickup (carbureted), I need to bring it up to temp, and check that the idle rpm is close to 700 (MT). Then, do I disconnect and plug BOTH vacuum lines from the distributor, or just one, and if so, which one? Then I set the timing to 0, and then I reconnect the lines, right? After I reconnect the lines, what should the timing read?

Here's a picture of the FSM that seems to say that I set it to 12, and then it should advance to 0 after the lines are plugged in? I'm confused.


Symptoms:
Currently the truck seems to run fine except for a rough idle. I have never disconnected the lines before when setting the timing. I just set it to zero because my sticker is unreadable, and the guys at the smog shop said it had to be withing three degrees of zero to pass smog. Acceleration and operation at higher rpms seems to be fine. The truck has run like this since I got it 4 years and 3000 miles ago. Truck also runs a little hot (on a hot day, with a load, it might overheat, otherwise it's fine)

 

Also, I did a compression test and got between 181-185 across all four cylinders. I guess that's why the rough idle is bothering me. I should be able to get this thing running like new with those numbers, shouldn't I?

 

The directions say (with vacuum advance cut) so it seems you would disconnect and plug the vacuum advance hose.

 

So I disconnect and plug BOTH lines, right? After plugging them, do I set it to 0* or 12*?

 

You should have one line from the intake manifold and one from the carburetor. The one from the carburetor is the one to disconnect and plug. Leave the other one connected.

 

I stand corrected... just found the manual and you do disconnect and plug both lines.
sorry.

 

Thanks! So after I plug them, do I set it to 0 and hope it changes to 12 after I reconnect them, or do I set it to 12 and hope it changes to 0 after I reconnect them? Sorry for being a total noob.