Dismiss Notice

Welcome To CK5!

Registering is free and easy! Hope to see you on the forums soon.

Score a FREE t-shirt and membership sticker when you sign up for a Premium Membership and choose the recurring plan.

Ever hear of a truck running too cold???

Discussion in 'The Garage' started by randy88k5, Jan 18, 2005.

  1. randy88k5

    randy88k5 1/2 ton status

    Joined:
    Nov 8, 2004
    Posts:
    1,248
    Likes Received:
    0
    Location:
    Lynchburg, VA, USA
    My friend has a small Nissan pickup, late 80s, 4 cyl, Auto. I helped him replace the alternator cause it was a PITA to get to. He said when he drives it, the needle never goes above the C mark. This was happening in the end of summer too. I said it must be a stuck thermostat. I changed the thermostat and flushed the system.

    I borrowed the truck yesterday to pick up some stuff since the Blazer is getting a lot of work done to it, and cant be moved right now. Since it was in the 20s here, I tried to use the heater, and suprise, no heat. The needle still read C. I guessed it must be a clogged heater core and a broken sending unit.

    After a few hours of driving, I pulled into a parking lot and left the engine running. I popped the hood and grabbed the intake plenum with my bare hands , just a little warm. The radiator and the hoses were almost cold, and the exhaust manifold was just hot enough I couldnt touch it for more than a few seconds. And this is after a few hours of driving.

    I have never seen or heard of such a thing. Everything in the engine compartment I could touch without getting burned in the slightest. Anyone got any ideas??? Thanks
    -Randy
     
  2. low 84

    low 84 Registered Member

    Joined:
    Jan 4, 2005
    Posts:
    45
    Likes Received:
    0
    Location:
    college station, tx
    sounds like a stuck open thermo to me, but you said you just replaced it. could have got another faulty one, i've seen more bizzar things. i would take the thermo out and check it in a pot of water on the stove and verify its operating correctly.

    does it have electric fans? mabey they are not kicking off
     
  3. sled_dog

    sled_dog 1 ton status

    Joined:
    Sep 3, 2002
    Posts:
    16,870
    Likes Received:
    0
    Location:
    Austin, TX
    stuck open or far too cool thermostat sounds like. Probably not running its top like that either. Engines are meant to run in a certain temp range.
     
  4. randy88k5

    randy88k5 1/2 ton status

    Joined:
    Nov 8, 2004
    Posts:
    1,248
    Likes Received:
    0
    Location:
    Lynchburg, VA, USA
    As for fans, no, just a single thermal fan clutch. When I changed the thermo, the clutch seemed fine.

    And I used a brand new stant, 195 degree IIRC. Guess it could be defective, but this problem was why I changed the themostat in the first place. Didnt help a bit.

    Thanks for the input.
    -Randy
     
  5. MOABDADC22

    MOABDADC22 1/2 ton status

    Joined:
    Jul 24, 2001
    Posts:
    1,348
    Likes Received:
    0
    Location:
    Cheyenne, Wy
    I would run a 160* or a 180* thermostat.
     
  6. ntsqd

    ntsqd 1/2 ton status

    Joined:
    Nov 28, 2002
    Posts:
    3,381
    Likes Received:
    0
    Location:
    So. CA
    Engines usually warm up faster with a higher temp t-stat. Lowest I'd go is 180. 160 is for some sort of race engine. Otherwise the clearences are wrong for that temp and it will wear out quicker. If 195 was stock, and the engine's stock I'd put that back in it after checking that it opens at the right temp.

    At those temps what happens if you block part of the rad with a piece of cardboard?
     

Share This Page