1976 Oldsmobile Cutlass AC

NERF_E

MEMBER
1976 OLDSMOBILE CUTLASS

I have a 76 cutlass supreme. From factory when the ac is on max the blower automatically goes to high and can't be controlled. Is there an aftermarket relay sensor that would replace the old one to give fan options as the ac don't cool as well in norm on hot days

3 Replies

FREEMBA

MECHANIC
1,152 POSTS

On very hot days the a/c will not cool as well as on cooler days or when the blower is set on HIGH. However, it still you should be comfortable with it set in the NORM position. If not, have the system checked to be sure it has enough "freon" in it for proper operation. The fact that it only cools well on MAX makes me suspect that it is a bit low on "freon."

SPONSORED LINKS

Was this

answer

helpful?

Yes

No

Wednesday, June 19th, 2013 AT 10:02 AM

NERF_E

MEMBER
2 POSTS

Pressures are fine and it requires 4 pounds which I had professionally done. When on high there is no bubbling in the sight glass on the accumulator to determine its low. I think the problem lies in the fact when its on MAX 80% of the air is circulated vs NORM allows 100% outside air affecting its cooling capacity. My duct temp on MAX is 42 continually and my NORM temp 60 on a 95 degree day. So I figured if I could control the fan setting on Max that I would do well for that older car.

Was this

answer

helpful?

Yes

No

+1

Wednesday, June 19th, 2013 AT 11:03 AM

FREEMBA

MECHANIC
1,152 POSTS

Likely a blend door not closing or opening fully when in the NORM position.
These doors are controlled by vacuum diaphragms under the dashboard. A vacuum line comes into it on the passenger side of the dashboard, goes to a junction and is then distributed to various vacuum operated devices/diaphragm. Check the operation of these devices. Seems that one isn't opening or closing the door completely.

Was this

answer

helpful?

Yes

No

Thursday, June 20th, 2013 AT 5:57 AM