A/C Question and New Member

Hey guys, I'm a new member and a new owner of a
Mazda B2200 that I resurrected from the dead, a tree had fallen on the roof and done some serious damage. Anyway, got that fixed and painted and now moving on to the AC, does anybody know if these trucks have a orifice tube or do they use an expansion valve and where either of them might be located on the AC system? I think I've got a blockage because I'm seeing really high pressure on the high side and a vacuum on the low side.
Thanks in advance!

Oooh, ooooh, oooh, Mr. Kotter, sir, I'll take this question!!!

These 1986-1993 Mazda trucks use an expansion valve, located on the evaporator, located under the dashboard, passenger side. The entire evaporator will need to come out from under the dash for you to unbolt the expansion valve, and the two big connections are in the engine compartment near the firewall. I've replaced the evaporator on mine (due to a leak), the whole job took a full morning even with the help of my 11 year old daughter.

Also, be aware that a new expansion valve may "appear" to only fit "backwards", but there's been a re-design.

That doesn't sound like an easy fix like was on my Ford pickup. Does the whole dash need to come out?

No, it can come out without the dash but the dash is easy to remove and reinstall. You could take the opportunity to service everything in the dash at the same time. That would include the blower, vents, and heater controls... The heater core does NOT need to come out.

Look here on how to: