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  1. #1

    Default 89 suburban hvac questions

    I recently picked up this suburban and the first day I had it i flipped on the blower and it came on fine and then quit a few minutes later. I'm looking for some tips on this.

    I have checked the resistor and it has power to it and good resistance.

    There is a fuse holder bolted along with the resistor. It had a 5a fuse in it that checked bad, so I replaced it with no change.

    I did a visual inspection of the blower motor and it "looks" ok, although I'm not sure how to check it electrically.

    There are 2 hoses coming out of the a/c core housing (the box the resistor is installed in) that look like water hoses that go to nothing. What are those for? Rear a/c?

    I have pictures, but I'm not sure how to attach them.

    - - - Updated - - -

    Ok, so i got the blower working, even though I couldn't tell you how, but there is no heat coming out even with the truck warmed up and I don't hear the a/c clutch kicking in like i did before.

  2. #2


    To upload pictures, click the icon in the reply toolbar that looks like a picture. It's 3rd from the right. There you should be able to browse and select the picture.

    I would definitely like to see some pictures to see what's wrong. I have a 91 which is the same bodystyle and I should be able to pick out anything looking not right pretty quickly.

    1991 Chevy Suburban 1/2 ton 2WD w/ chevy SBC 350-3/4 ton drivetrain upgrade w/4.10 gears 200K miles
    2005 Saturn ION-2 Stock 265K miles
    1982 Bronco, 1993 Bronco (sold), 1971 M35A2 Deuce and a Half

    There are 10 kinds of people, those who understand binary, and those who dont...

    Remember kids, the only difference between screwing around and science is writing it down- Adam Savage

  3. #3



    Figured out why there was no heat.

    One of the previous owners had put a bypass hose from the radiator to the port by the distributor. No clue why. So I. Hooked up the 2 hoses I mentioned in the first post and now I have heat. I thought perhaps it was bypassed because the heater core was leaking, so I expected to see a leak in the floorboard when I put the hoses right, but it didn't leak.

    Any idea why else someone would go to the trouble to bypass that?

  4. #4


    It was most likely bypassed because it leaks like you guessed. However, it may not be apparent that it's leaking and may take a day or two to be noticeable on the floor.

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