GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Page 1 of 4 123 ... Last Post byLast Post by
Results 1 to 10 of 38

Thread: Condenser Fan

  1. #1
    Sr. Engineer
    Join Date
    Aug 2009
    Location
    Virginia Beach, VA.
    Posts
    337

    Default Condenser Fan

    '91 Silverado, 5.7L 350

    Where is the condenser fan located??

    On my truck, I have some cooling unit behind the grill....didn't see what he was connected too.
    Then my condenser, then my radiator.

    So just wondering where the Fan Assembly for him is located.
    Is he between the condenser and radiator??
    Cause he ain't in front between the grill and condesner.

    And I think that is what is causing my High Side pressure on my A/C to jump to 400psi when I cut it on....and it gets really loud.
    But when I am driving (and thus air is cooling the condenser) the thing is quiet and seems to run fine. Of course I can't check the pressure then. :D

  2. #2

    Default

    The engine driven fan serves as the condenser fan and radiator fan. No separate electric fan.

    The extra cooler in front of the condenser is most likely an auxiliary transmission cooler.
    When you hear hoofbeats, look for horses not zebras.

  3. #3
    Sr. Engineer
    Join Date
    Aug 2009
    Location
    Virginia Beach, VA.
    Posts
    337

    Default

    Ok....

    Well any ideas as to why my high side is hitting 400 PSI??

    Low side is about 40 PSI, if I add more freon, then things really start getting loud at the compressor....

    A/C blows cool....but the noise when I am at idle plus the High pressure readings worry me a bit.

  4. #4

    Default

    Missed that about the pressure before. Most likely caused by a restriction somewhere, first guess would be the orifice tube.

  5. #5
    Sr. Engineer
    Join Date
    Aug 2009
    Location
    Virginia Beach, VA.
    Posts
    337

    Default

    I was thinking of him as well....
    I guess I will be evacuating the system. :(

    I have the tube on hand....I should have replaced him back when I did this all before....oh well.

  6. #6

    Default

    What is the suction line pressure, if you have a restriction of that magnitude the suction side should be dropping into a vacuum. In fact it sounds like the system could be overcharged and liquid is comming back to the compressor causing your noise, also would like to know what your superheat and subcooling is if your able to keep it running that long
    Last edited by Bigg Ron; 06-13-2011 at 04:26 AM.

  7. #7
    Sr. Engineer
    Join Date
    Aug 2009
    Location
    Virginia Beach, VA.
    Posts
    337

    Default

    Well on my low side I read right around 40 PSI.....
    Maybe a little lower....
    I tried adding in more freon, cause I thought it should be up around 45 PSI.....but that just made the noise at the compressor worse.

    And of course on the High Side, with that high pressure, causes some severe heat on the guage connection, so you about burn your hand removing the high side connector.

    I guess I could try letting some out to see if that helps first, before emptying the whole system.

    But I don't think I used but 3 cans (4 at the most) when I filled him.

  8. #8
    Sr. Engineer
    Join Date
    Aug 2009
    Location
    Virginia Beach, VA.
    Posts
    337

    Default

    Ok, I released some of the freon....
    High side went to 250PSI, Low side dropped to 25 - 30 PSI, compressor stayed on, no cycling.....blew cool in the cab.

    Now it ran quiet in the driveway at idle....so I took it on the road.
    About 2 miles, when I came to a stop-light, it started to make some noise.....once I started driving again, it calmed down.

    I have not re-checked the pressure....will have to do it later.

    But I am thinking at this point, it might be the orifice tube.

  9. #9

    Default

    Not sure about your model but many gm trucks condenser fan and radiator fan are one and the same. However they are clutched and the fan rotation adjusts with the engine rpm. Over time the fan clutch weakens and causes poor air flow. A A/A tech told me that this contribute to many compressor failures. Try placing a fan in front of the vehicle and recheck the pressures. Also clear any obstructions to air flow. Seem odd a Radiator flush can help also.

    I would think it would be the restriction orifice initially. However if that is the problem, then you may have bigger problems. Something had to contaminate it. Failing compressor or something else. Who knows?
    Just food for thought. Hope it helps!

    This is my 2nd attempt at a reply. Hope you get one or both.

    ---------- Post added at 06:26 PM ---------- Previous post was at 06:23 PM ----------

    I meant I would not think it is a restricted orifice initially unless you are aware of other issues. Sorry for the Typos

  10. #10
    Sr. Engineer
    Join Date
    Aug 2009
    Location
    Virginia Beach, VA.
    Posts
    337

    Default

    Ok...
    Went out and swapped out the orifice tube....the one in there was gunked up on the side that is facing the condenser....
    So put in the new one, put it back together.
    Pulled a vacuum and then stuck in about 2.5 cans (12 oz.) of 134a

    Now the low side would read around 30 psi, and the high side would get 250, and then climb to around 300....
    Started makeing noise at the compressor again, loud noise...

    Turned all things off and let it sit for a few min. to cool down....
    Then I turn it on and again the pressure started out around 30psi, dropped to about 25 and then settled out around 30.
    High side started ~250 and then just kept slowly climbing to 300psi....
    Let it run for a bit, the compressor never shut off......never made any noise....
    And it blew cool

    I think the compressor will need to be replaced.

    ---------- Post added at 10:39 PM ---------- Previous post was at 09:38 PM ----------

    I came across this site (only thing I can find on this issue).....
    http://www.autopartsdistributors.net...spx?gfid=c6102

    It shows an oil capacity of 9 oz.
    So does that mean that is how much oil needs to be in the system??

    I have not been able to find anything on this model compressor (other than the above site) saying how much oil is supposed to be in the system....

    I am thinking now, that when I put this compressor, I may not have added enough oil to it.....and of course now, there is no way of knowing how much I put in.
    So I probably have screwed up my compressor.

Page 1 of 4 123 ... Last Post byLast Post by

Similar Threads

  1. New Condenser 2004 Chevy Silverado 3500 8.1
    By ChevyFan in forum Chevy Parts eBay
    Replies: 0
    Last: 06-14-2010, 12:30 AM
  2. New AC Condenser 2009 Chevy Silverado 2500 HD WT 6.6 Tu
    By ChevyFan in forum Chevy Parts eBay
    Replies: 0
    Last: 04-11-2010, 03:50 AM
  3. New AC Condenser 2005 Chevy Silverado Ss 6.0
    By ChevyFan in forum Chevy Parts eBay
    Replies: 0
    Last: 04-11-2010, 02:40 AM
  4. Condenser Box or Heater Core?
    By c_m_chance in forum General Chevy & GM Tech Questions
    Replies: 3
    Last: 07-28-2009, 03:51 PM
  5. How to clear drain from AC condenser
    By jimgundlach in forum How-to Guides
    Replies: 0
    Last: 06-08-2009, 06:12 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •