I recently converted my ac over to 134a after suffering a catastrophic compressor failure. I replaced the compressor, dryer and expansion valve. Now, the air blows pretty darn cold as it should when driving - but - subsides considerably at stop. I was thinking that it's because the air isn't moving through the condenser, furthermore, that because my system was designed for r12 and the fact that 134a is not as efficient... you get my drift.

So is it possible to mount a small fan to the front of the condenser?

if so, where would be the best power source?

My recent upgrades:

New waterpump, hoses, t-stat, 130amp alty and ac equip, plugs , wires, cap,rotor.. and other usual suspects.

 

First inspect your radiator's fan clutch to make sure it isn't slipping. If it's slipping you're getting less air flow than you need to have.

 

R134a does not function well in any system originally designed for (and already operated with) R12 refrigerant. Eventually the R134a will liquefy the dessicant in the drier of your R12 system and you will suffer another catastrophic failure; probably the compressor. It could take a few years depending how much you use the A/C.

To your question: there should be plenty of room behind the front grille assembly, so you could install a "pusher" fan on the front of the condensor to keep the system chilly when idling.

Best power source is to connect the power lead from the fan directly to a 20-30 Amp relay setup and then connect the relay power lead directly to the battery.

Check your fan rotation to make sure the polarity is correct before making all final electrical connections.

 

I replaced the drier when I installed the new compressor, wouldnt the new drier be 134a compliant?

if not, would it be a good idea then to replace the drier at the beginning of next summer?

 

If you replaced the drier then you should be OK -- all new driers should be 134a compatible. Good move.

 

If the fan is slipping, maybe switching over to a Viper eFan Mopar Performance would be the ticket. The eFan can run at two speeds and runs automatically or manual override when the AC is running. You will pick up about 8hp, 11tq and 1-mpg improvement overall.

This is the Viper fan for the 3.9L, 5.2L, 5.9L, and 8.0L Magnum engines. It has a two speed motor to drive the fan.

Complete Viper fan kit for Dodge Ram. Kit is complete with the following:
Viper Electric Fan P5007266
Flex-a-lite controller 31147
Pigtails 5014007AA

This fan is a replacement for the stock clutch fan. Removal of the stock fan shroud is not necessary as the motor and fan can mount into the existing shroud.

A 25.5-inch-wide electric fan-and-shroud kit (PN P5007266) listed in the Mopar performance catalog for a V-10 Viper crate engine sucks air through the stock 26-inch-wide radiator. Adapter brackets make up the difference and bolt the shroud to the radiator. Note the four square relief flaps that open at highway speeds when the fan is not used as much.