I have a 1979 Ford F150 1/2 ton P/U XLT, 4WD 6.6L 2BL OHV 8cyl that I'm trying to put A/C back in. The truck had factory air, but the evaporator is the only original part in this setup (along with the controls inside the cab on the dashboard).

The new compressor is working. All the pressures look good (the low side is around 35 to 40). But we're finding that the air out of the vents is only dropping 20 degrees max. We've checked to see if the blend door was not working and it was getting heat from the heater core. We blocked off the heater core completely with the same results. It just doesn't seem to be getting cool enough. The large fittings on the firewall should be cold (maybe 40 degrees), but it's only cooling to about 79 degrees, about a 15 degree drop.

We cannot see into the evaporator box to see if there is an expansion valve in the system, but we did not put an expansion valve in with the new system we put on.

Any advice appreciated!

Thanks,
Lisa
Houston, TX

 

Hey I read on another forum where you were working on this. Please post some updates Id love to hear how you got it to work!

 

User "liasgk" - Last Activity: 07-23-2012 04:18 PM

Hasn't visited in almost a year..... odds aren't very good that there will be a response.

 

She must've become disillusioned after 392 views and no responses. Can't say that I blame her, but with only one post in over a year, I think we lost her.

 

There are a few things I got sucked down good? OK I suppose you are using
134 OK origional F12 we know that. Napas quick conversion kit works good
on F12 systems, its a trick kit that tricks the system into thinking its F12
The big factor with A/C is the ambient temp. I wont work when its too cold
out couple second it will kick off. Next you wont get meat freezer flow
either. If its 100 degrees out & you pull 20 or so degrees (dont forget its
getting rid of the humidity) you got a deal. Example yesterday a high
humid 92 I go in house is 80 with no humidity, it felt cold. Normally stick
a thermometer in the center register-- 45-50 degrees should drop it 20
degrees......