[arveetek]

The 84 up system is much easier to change and bleed, but has been known to leak around the switches in the filter base. The 82 to 83 style is much simpler, but is harder to bleed the air out of the system after changing. My personal opinion is go with the 82-83 dual spin-on filter setup. That's what I have on my '81. I also relocated the secondary filter to the firewall. The original spot on the back of the intake manifold was a bear to get to. Very hard to change, had to unscrew the fuel lines each time you changed the filter. Now I can just grab it and spin it off.

There are two wire terminals on the pump, with a third terminal on the fast idle solenoid if it's there. It's just a solenoid plunger that pushes down on the throttle lever to speed up the engine when it's cold. Sometimes these get removed during service and never put back on.

The center terminal on the pump is the fuel-cut off solenoid. This keeps the engine running when 12v+ is connected to it. (You can just use your original coil wire here).

The other terminal on the passenger side of the pump is the HPCA (housing pressure cold advance). This basically advances the timing when the engine is cold for easier starts. The HPCA and the fast idle solenoid are wired together and connected to a temperature switch located elsewhere on the engine. Or, you could simply put a switch in the cab and turn it on when the engine is cold, and shut it off after it warms up a little bit.

Casey