Vents for A/C

[Andy4639]

Been some time since I psted on here. My time has been spent on work,kids and golfcarts. I just got the money to do some upgrading on the old truck so it will be ready for my son next may when he turns 15. I got the A/C going again and have a ? for you all.
The passenger side vent that is suppose to be operated by your vacume is not on the truck I took them off. I also had broke the flapper up in the cowl area that lets fresh air in and cuts off when A/C is on. My question is would it make the air colder if I block that opening off to keep from having hot air coming in even knowing the vent in the cab is closed?
#2 I herd someone mention a bigger fan motor to help with air circulation. What else will fit in the opening?
A/C air is 40 degree's but you have to leave it on high all the time.
New compressor,acumalator,condensor, hoses running 134-A.

[centsless]

#1 Yes, closing the opening will make the A/C colder. That will make it so the A/C is cooling cool air, not hot air.
#2 I do not know of another blower motor to fit the truck. Hopefully someone else will chime in on that one.

[lbpd719]

I know that if you check around there are shops that will rebuild your blower motor, and possibly be able to give it a little more juice. Might want to check your resistor/switch as well just to make sure they are working properly.

I might get with you on the AC project though if you don't mind. I am getting ready to redo mine sometime this summer.

Regards,

719

[GMC Jim]

GM used 2 different motors with their heater and air conditioning systems... The heater only system used a blower; specs are:-13.5 volts; 8.25 amps max; RPM 2550-2950 max. The blower used with heater/air conditioning system; specs are:-12 volts; 16.5 amps max; 3700 RPM minimum. The air cond systems used a relay which controls the blower high speed selectiom. This relay is located inside the firewall; near the top right rear of the glove box. If this relay is not operating, there be no high blower speed. This can be checked by jumping a wire from the postive battery terminal to the blower wire which should be accessible near the blower on the engine side of the firewall. If the speed ( and output) imcreases as compared to the high blower switch position on the air cond. control in the cab; then the relay is not operating. Check for proper grouinding of the relay as this is a fairly common cause for malfunction

[GMC Jim]

The 2 blower motors described in above message will interchange with no problem.......... Jim

[Andy4639]

Thanks for the info. I will check the blower with the jumper soon. I pretty sure I have the A/C blower and I know I have the relay, but haven't checked it for operation though.