PRIrish

What year C4 heater/AC blower motor/fan will best fit a "76 that has AC?

doctorgene

Yes Sir; Just buy a new AC Delco from GM parts direct, or have your local dealer get one from the A C Delco parts depot. They will fit perfect, & work wonderful. Have a nice day. Gene

bruiser

I used a Four Seasons blower motor from Rock Auto.
Part # 35344 fits the following.

BUICK ELECTRA ESTATE WAGON (1988 - 1989)
BUICK LESABRE ESTATE WAGON (1988 - 1990)
CADILLAC FLEETWOOD 1984
CADILLAC FLEETWOOD FORMAL 1984
CHEVROLET ASTRO (1996 - 2005)
CHEVROLET BLAZER (1995 - 2005)
CHEVROLET BLAZER TRAILBLAZER (1999 - 2001)
CHEVROLET CAMARO 1989
CHEVROLET CAMARO IROC-Z 1990
CHEVROLET CAMARO RS (1990 - 1992)
CHEVROLET CAMARO Z28 (1991 - 1992)
CHEVROLET CORVETTE (1987 - 1996)
CHEVROLET CORVETTE ZR-1 (1990 - 1995)
CHEVROLET S10 PICKUP (1994 - 2002)
GMC JIMMY (1995 - 2005)
GMC JIMMY ENVOY (1998 - 2001)
GMC JIMMY SLS (2002 - 2004)
GMC SAFARI (1998 - 2005)
GMC SAFARI XT (1996 - 1997)
GMC SONOMA (1994 - 2002)
ISUZU HOMBRE (1996 - 2000)
OLDSMOBILE BRAVADA (1996 - 2001)
PONTIAC FIREBIRD (1989 - 1992)
PONTIAC FIREBIRD FORMULA (1989 - 1992)
PONTIAC FIREBIRD TRANS AM (1989 - 1992)
PONTIAC FIREBIRD TRANS AM GTA (1989 - 1992)
PONTIAC FIREBIRD TRANS AM GTA SE 1989
Please refer to catalog for application details.

ESU

Im looking to do this mod to my 82 as the a/c season is fast approaching. I believe a spacer has to be fabricated yes? If so what are you guys using to make the spacer and how thick does it need to be. Since this is an apparently popular mod you would think one of the after market shops would pre make one for us.

ESU

Bruiser, I bought this fan ,#35344 however the wiring jacks are different? The one in my car has 2 seperate plugs 1 on top , 1 on bottom while #35344 has 2 plugs in 1 large socket. Is this how yours was? How did you hook up the wires?
Thx Cory

SanDiegoPaul

yes the wiring is different and needs to be adapted. Using a spacer and getting it installed with the blower was tough for me. what I decided to do was use of quarter 20 bolts and Double – nut them through the firewall. This way I had studs to hang the parts on, and all I had to do was get one hand in the fender to put on one nut at a time.
it may be a pain in the butt, but this is a worthwhile upgrade.

ESU

Paul, how did you do the wiring? I have the spacer already made, with longer screws, just need to figure out the wiring and get it all in there.

SanDiegoPaul

You can buy the correct connector for the fan motor. All you have then is two wires;the connector has one positive one negative wire sticking out of it.

bruiser

This is what I used. I got it from NAPA.
Part Number: ECH EC116
Product Line: Echlin Ignition Parts

daanbc

You don't need to buy the whole fan. Just by the squirrel cage. It cost about 12 bucks. It's the additional fan blades and pitch of them that increases the air flow. All the motors put out the same and all require the same 12 volt. The older motors just need heavier/thicker gauge wire. As soon as you do the ground wire, you will hear the increase in that wire alone. As for the spacer alot of guys are using wood. I just took the whole fan box out, and cut off where the blower fits, and fiberglassed it out an inch. This way I also increased the air passage that the new fan puts out. If you just go the spacer route, you still have the same size hole/passage for the air to go thru. But you will feel the diff!!

ESU

Thx all, will pick up the connector. Dont have a napa near me but autozone or pepboys should have something similiar. I made my spacer out of wood. Looks like a real bear to get that old motor out. AC compressor has to move, radiator overflow tank has to come out. Oh yeah, a 3 beer job for sure.

'75

You should measure and make the spacer only as thick as needed. Mine is 3/4". Extra space at the end of the blower wheel will reduce the air flow.

ESU

Made it out of 3/4 plywood.

chvet73

I have to respectfully disagree with Daanbc. I found the C4 fan is more powerful. I have tried several different motors and the C$ is by far superior.

daanbc

That's ok to disagree. But all the motors draw the same volts. The newer motors MAY put out an extra 100-200 rpm's. But that is not where you are feeling the difference. The difference is in the blades pitch. All I did to mine was replace the squirral cage and replace the ground wire with a thicker one, and placed the ground in a better location. Now the air blows like a hurricane. Same 34 year old motor.

You can check it out for yourself once you buy a whole new fan. Just take the cage off the new place it on the old motor, replace the ground wire with a thicker one, and connect to a batt.

ESU

Why is the thicker ground wire so important?

riverracer au

daanbc

From "MRVETTE"

IT IS NOT On the Damn + feed through the relay, not on my '72 here or any other shark I have worked on.....the voltage drop is because they used too thin a wire on the GROUND side of the motor frame to the engnine block....this wire is like a 12 ga or so from the starter/bellhousing area, with a 3/8 diameter loop on it....and it's black fairly thin wire....going up to a junction feeding the relay ground for the coil, the wiper motor ground at frame...plugs into the driver's lower front, AND the blower motor frame....

keep one thing in mind....the damn blower motors for all the GM cars of the ear were nearly identical...A-B body F body, G body, even the Vette.....NOW the other cars are steel, and as such had NO ground voltage drop....typically....SO the fan motor had fulll voltage throug the exact same circuits the Vette has to run the positive side of things.....

so having a full load of only 11 volts across the fan motor with everything running full bore...tell ME, that your ground wire is too thin....

BTDT....beleive me when I say....it wasn't untill year or so later I upgraded the motor/blower assy with C4 stuff....

the stock motor/blower seemed to nearly double it' output...no lie....

gotta unnersand elek tronics....lek trick als to figger out why....

don't matter for this discussion....

At any rate, from what you said above....the GROUND wire needs be much larger, and while you at it, redoing the harness....put the damn ground tab/loop up top where it belongs so not confused to some mekanik when changing starters...another problem with that wire loop location.....


tHIS IS FROM 3-27-07 (C4 fan/blower install??)

noonie

There was a guy on here back in around 2004 or so that was doing a physics project for college.
He had very detailed results for several blower motors he had tested including voltages, amps, rpm, and cfms.
I can only go back to 2009 in searches, wish I would have saved it.

Generally
-The newest blower motors that fit run a higher rpm.
-A used motor has substantially less rpm than even the same replacement new motor.
-Newer drum has more cfm
-Substantial rpm difference between battery voltage and alternator charging voltage.
-more rpm with wiring upgrades

That's all I remember, maybe someone can find the original posts.

mikejpss

Just wanted to relay MY experience on an electrical connection , it would be the female 2 prong plug at the accumulator on my trucks a/c system. I knew the plug was bad by testing it with a volt/ohm meter . NAPA had one for $29.95 ... thats right, just the plug -very similair to the one pictured . Told them I would jump the fence on a junk yard at night and steal one before I paid $30 for theirs. Drove across the street to AutoZone and got one for $5.99 plus tax. you tell me where the difference was. It was in my pocket. I actually drove back to NAPA to show them why AutoZone is kicking their azz in this town.