Any tips to get more air from blower motor?

[BruthaMan]

One thing I've noticed in the Texas heat, after restoration, is that I'm getting very poor air flow through the heating/ac ducts.

We recently stripped out the cab to do some additional work and install a new deck head unit and went ahead and checked all the connections of the duct work.

Even took felt with strong tape on the reverse side, to double seal the duct work. Double checked that the "flaps" were opening when changing from heat to vent to AC, no problem there.

It has a new blower motor. I read a thread here on the forum that someone suggested getting a blower motor for a 95 extended cab. We tried that, taking the new blower motor out for a trip to Orielly's. The blower motors looked identical and we hooked both up to a battery there and there was noticeable appreciation in blower speed between the two.

Any tips for getting more air flow? Are there any "super" blower motors out there that can send a decent flow? Right now, high is maybe the equivalent of the lowest setting on a newer car. It's steady, it's cold, but the flow is so minimal that it really doesn't cool the cab very much.

[Matt Man]

my truck had the same problem, the flap that allows the air to come into the cab you need to check to see if the clip on their is broken. i found this out because on max AC there should be no air going through the bottom vent and should only come out of the top vents. If its not make sure all your ducts are securely fit onto the vents. worked pretty good for being converted to 134 was 105 degrees today worked great.

[875.3CHEVY]

whats wrong when you can floor it and it gos to floor air.also i blocked off the passenger duct cause im miising it and the far left one,and man what a diff in flow.so i to am looking for this more aggressive blower motor.

[79gmcc15]

Originally Posted by 875.3CHEVY

whats wrong when you can floor it and it gos to floor air.also i blocked off the passenger duct cause im miising it and the far left one,and man what a diff in flow.so i to am looking for this more aggressive blower motor.

Did you have vacuum hooked up to the ball on passenger side? I heard that if you don't,it can cause the change.

[TheApocalyptican]

Originally Posted by BruthaMan

Any tips for getting more air flow? Are there any "super" blower motors out there that can send a decent flow? Right now, high is maybe the equivalent of the lowest setting on a newer car. It's steady, it's cold, but the flow is so minimal that it really doesn't cool the cab very much.

A couple of things I would figure I'd mention as I have much the same problem in my s-10 blazer. I do however, have it working better than it ever has now, but it's still weak compared to newer vehicles. First thing is to be absolutely sure that there are no air leaks anywhere. Even the smallest leak can have an effect on the volume of air that comes out the vent, and if there are several small ones, you could be losing a decent amount of air. The second thing is to make sure that your alternator and charging system are putting out a good voltage. In my blazer I upgraded from the stock alt which sat at about 12v on a hot day to an upgraded bigger alt, which sits at about 14v on a hot day. That extra 2v made quite a big difference in the amount of air coming out of the vents due to the blower seeing more voltage, and thus blowing harder.

[motornut]

not sure if someone mentioned it but the floor/def air valve in my 88 sub had three places to put the rod in ,more floor or more def or equal to both.
(the pic)My clip that broke was this one on the front,you have to remove the other air tube over this to see it.
But check the cables shown(arrows) for bends

[BruthaMan]

Hi Everyone,

Thanks for the great tips. I've not yet made an opportunity to look at these yet, but they are on my list.

When we pulled everything out of the cab this last time, we took everything apart and used some felt with really sticky back side to line the inside of each receptor to make sure it had a good seal.

We have checked to make sure the door is opening and closing and it is. There are a couple of things I'd like to recheck, just to be sure.

One the alternator, I'm running a 100 amp alternator. I do have electric fans on the radiator and we've checked with those on/off and didn't make a difference.

I'm going to wait till it cools down some before digging back into it. These 95+ days are killers on a big man! I don't drive it daily (maybe one or twice a week).

[tucsonjwt]

motornut - where did you get that plastic clip? Mine is broken - white plastic split in two down the center. Do you have a part number?

[tucsonjwt]

I assume that you are completely sealing the joints where the pieces of duct join together. I used metallic residential HVAC tape to seal my ducts. The few factory screws here and there just don't make a tight connection. I think when these ducts get old they lose their true shape and flex too much to make a good seal.

[Stitch]

Originally Posted by tucsonjwt

motornut - where did you get that plastic clip? Mine is broken - white plastic split in two down the center. Do you have a part number?

Look through joe321's recent threads. He posted a thread about that little white clip and a link to buy one

[joe231]

Originally Posted by Fat Hoe

Look through joe321's recent threads. He posted a thread about that little white clip and a link to buy one

here it is

http://67-72chevytrucks.com/vboard/s...d.php?t=410760

[motornut]

got mine from my 87 parts truck to fit my 88 ,but can be bought

[87chevy.com]

nothing like churning up an old thread

I wanted to check this piece for the longest time when I first read this thread. My vent output was fine in the morning mostly because it wasnt hot outside yet.. but in the middle of the day, it didnt feel the same... Just like other members noted, that on A/C Max there should be no air on the floor vent, and I had some going there ... well finally spent a few minutes after work and removed the glove box, and the a/c ducting and found my plastic tab broken. Cheap looking thing... anyway I forgot to grab a pair of pliers from my tool box at work so I cant pull that dang pin out... I already stabbed myself by trying to press that pin out with a flat blade... I even thought.. man I'm going to stab myself.. and I did... sob.

Well I called GM and spent about 5 minutes on the phone with the dude and hes like yeah I got something that sounds like what you need. I was like sweet... For those who are interested in saving the next counterman the hassel, heres the part number:

3018715 connector group 9.786 list 2.39

Tomarrow I will remove and install the new connector/tab piece and seal up the ducting with the butyl tape. Its wicked good sticky stuff when its heated and makes water tight seals. Good enough for my truck

clint

[TheApocalyptican]

Originally Posted by 87chevy.com

seal up the ducting with the butyl tape. Its wicked good sticky stuff when its heated and makes water tight seals. Good enough for my truck

clint

That is exactly what I have been planning on doing to most of the a/c ducting in my Burb! Used it in my Blazer, and its perfect for sealing the ductwork.

[nikwho]

Originally Posted by 79gmcc15

Did you have vacuum hooked up to the ball on passenger side? I heard that if you don't,it can cause the change.

Any way you can elaborate or show us a picture. my blower barely blows in heat or defrost mode. The vaccume line that comes out through the fire wall is hooked to nothing. Where does your's go?

[87chevy.com]

Well, my expectation of the vents blowing like the BMWs I work on blew right out the window... lol. But its definatly an improvement. the tab was broken in 2 spots actually. I replaced it no big deal, and I found that a vacuum line going to the flap actuator, only operates on MAX... the line appears to be crushed by the heater box, and where its under is a stud there and the nut to loosen is on the engine bay somewhere.. oh well.. it works because I can see it working.. oh well... thought about just cutting it and join the 2 back together..

clint

[motornut]

does this help?

[87chevy.com]

Thanks for the photos, Ive got nothing in those pictures .. I stuck a 5.3 in there.. for a visual, if you were to remove the glove box, its the a stud on the upper right on top of the box... i probally will just cut and splice it or something... I think its necessary to remvoer the evap case... unless i remove the case housing and reseal it.. hurm..

clint

[motornut]

I'm trying to remember i think the box seperated when i removed the bolts doing the heater core,i know i removed inner fender to get at a lower bolt

cut and splice would be the easy

[Justins76]

Originally Posted by 87chevy.com

phone with the dude and hes like yeah I got something that sounds like what you need. I was like sweet... For those who are interested in saving the next counterman the hassel, heres the part number:

3018715 connector group 9.786 list 2.39

For those mail order folks, Classic parts also has this part for $1.95. Mine even came in a GM bag. Their p/n is 68-248. Might be worth it to pick up a few when ordering other parts from them and keep them in the "spare parts" box.

[87chevy.com]

hey motornut, thanks for the photos, your tabs broken like mine was lol. I went to the junk yard earlier and seen that stud... yeah Im not gona remove the air box just for that... cut and splice one of these days..
clint

[gchemist]

Cut the ground on the fan. Reroute it to the back of the alternator bracket.

[Stitch]

Good idea. A better ground is always good
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