My factory air works fine in my `65 and blows around 42-43 degrees, colder on cooler mornings, but there just isn't enough airflow coming out of the vents. I know I can't compare it to a newer vehicle but my truck blows enough air through to practically blow your hat off. The Buick has 3 fan speeds and they all work so it's not a problem with anything electrical. Can anyone recommend maybe a different fan or a blower motor that runs faster? Any suggestions would be greatly appreciated. It's summer here in Florida, and for those of you who have never experienced that, well, you're lucky.
Bill, have you already checked all the joints in the ducting for leakage? If every joint between the fan motor and the outlets leaks just a little bit, it can really add up. Devon
If you can get at it, check the evaporator for crud. As many years as the car has on it, insulation, dust bunnies, etc., can be built up on it.
Definately a valid point if your evaporator hasn't been pulled out of the case. Here was a picture of mine when I opened the HVAC box. Sure it would likely still make plenty of cold air, but flow was going to suck. Also when I put it back together I accidently got the positive and ground wires swapped on the blower fan. The fan ran fine, just unknowingly to me it was turning in reverse which kills the air speed ou: When I figured it out the air output at the vents was at least 4 times as much.
TheSilverBuick. That's a perfect example of what is usually found inside the evaporator case on older cars. Thanks for the pics! Until you actually see it, it can be hard for some folks to justify the work to open up the evaporator case to clean it. Reversing the wires on the blower motor is an easy mistake to make. I've been bitten by aftermarket blower motors and cooling fan motors that were wired backwards internally. In either case, that's a real head scratcher until you figure it out.:shock:
I can see this could be a likely scenario. After all, the car is 46 years old and to my knowledge the evaporator box has never been apart. Not looking forward to that job but down here A/C is a must in the summer. I did look at this as a possibility. I replaced one of the hoses that was cracked, the others looked good. Unfortunately, none of it helped.
I thought about my evaporator possibly being dirty a while back, and I decided to pull out my blower resistor to take a look. My evaporator was actually pretty clean. I don't know if that's an option for you , but it beats opening one of those cases.
Unless you have rat nests or leaves in the evaporator box you could probably acid wash the coil through the blower resistor hole if it's nasty, and restore most of your air flow.
I was thinking shop vac piped through a heater hose into the resistor hole. Careful if you put any kind of "cleaning" chemical in there for at least two reasons. 1) You don't want to be "gassed" by the fumes next time you are driving the car and 2) Any spill over that makes it to the heater side of the HVAC system will drip right on to your carpet. If your drain tube is blocked/plugged it will likely spill over, especially if the fan kicks on while there is still a puddle of "cleaning stuff" in there.
Very valid points. I wouldn't recommend any harsh acids to clean the coil, but detergent style cleaners instead. The condensation will flush the cleaner out.
I've done this on a few vehicles. Strong mix of Simple Green or Purple Power through the resistor or blower hole via a garden sprayer (after vacuuming thoroughly with a shop vac w/small heater hose attachment). Then flush with a garden hose using a nozzle like from a 90wt gear lube bottle to "pressure wash" the area. Anything that spills out onto the floor is basically soapy water. It won't harm anything and will dry with good airflow from a fan. Yea, it works good...sometimes. The results are always "better" than when you started. However, this method still leaves a lot of debris impacted deeper in the fins of the evaporator. The end result depends on how much gook is down inside the evaporator fins. I've had evaporators that couldn't be cleaned well even out of the vehicle. Getting "everything" out of the evaporator isn't really important if the debris is just leaves and dirt. It's a totally different story if there was ever a mouse nest in the evap case. That smell can permeate the whole system, and often the whole car.
Re: How can I get more airflow from the a/c I rarely contribute to the conversations here but it was my review of the comments that ISRX put here and to try it myself: My issue was low air speed from the vents of my 1972 Skylark even after replacing the blower motor and pulling the fender, etc. So yesterday I pulled the resistor plate on the ac box and looked in with a light and OMG, leaves and some kind of built up crud from 1972 I gather could be seen. Anyway I proceeded to spray Purple Power in a stream on as much of the evaporator as I could over the course of about an hour. And sure enough the crud started to melt or dissolve. Then I work on getting the leaves out with a vacuum attachment, but the best was to simply turn on the blower motor and let the leaves find the easiest way out, via the resistor hole. Then I took a garden hose and started spraying a stream of water thru the hole onto the evap. Took me about 2 hours but what a difference. It feels the way I thought it should blow. Thanks.
Yeah, I still haven't done anything about it. I guess I get so busy with other things that I never seem to find the time, or make the time to get to it, and when I do I seem to get sidetracked to more important things, like building a cowl induction hood :grin: But it's getting hot here now so I've been thinking about the a/c again.
the blower may not be your problem. check underneath with regards to vacuum and flexhose integrity. mine didnt blow well until allthat was resoved,now my wife wants it turned down 2 notches,marty
