1. Registration trouble? Please use the "Contact Us" link at the bottom right corner of the page and your issue will be resolved.
    Dismiss Notice

New Water Pump Higher Temp?

Discussion in 'Early CJ5 and CJ6 Tech' started by Mr Plow, Jun 21, 2016.

  1. Mr Plow

    Mr Plow Member

    Hi All, I barely know how to use a wheel barrel but the other week my old water pump was starting to throw up antifreeze from the weep hole so I got a new pump and installed myself. I have two temp gauges. One in block and the other above the thermostat (brand new 185deg). Now with the new WP my engine temp creeps up higher (almost past the 'H') than before. At that point the thermostat finally opens. What would cause that? Is it simply lack of coolant? I have a cj5 1966. Should I even worry about this. Thanks guys!
     
  2. uncamonkey

    uncamonkey Member

    Thermostats do that cycleing thing when they warm up. As long as everything is good after it warms up, don't worry. I had two temp gauges on my 350 and it was interesting to watch how each side of the engine changed temps as you drove it.
     
  3. Glenn

    Glenn Kinda grumpy old man Staff Member

    Does the new thermostat have a weep hole? It needs one to keep air from being trapped.
     
  4. Mr Plow

    Mr Plow Member

    Hey guys thank you for the replies! Did you mean the new water pump having a weep hole? yes the new one does but smaller than the wep on the original. Yeah I thought if it does finally cycle that I would be fine. all new to me bUt enjoy learning about these vehicles thanks again for the input!!
     
  5. Glenn

    Glenn Kinda grumpy old man Staff Member

    No the thermostat itself should have a little hole in the body of it to allow a bit of water through it. That will allow any air to be bled out plus it helps the water temperature to equalize so the thermostat will open when it should.
     
  6. PeteL

    PeteL If it wasn't for physics, and law enforcement... 2024 Sponsor 2023 Sponsor 2022 Sponsor

    The thermostat flange should have weep hole, to pass any bubbles and ensure the hot coolant actually reaches the thermostat.

    Also, after draining and refilling coolant, the system may need to be burped before it settles down.

    What engine is this?
     
  7. Mr Plow

    Mr Plow Member

    Ah, ok will check those flanges. I have the f 134 engine. How do you burp it? Just run then top off coolant after system cools back down? Thanks for the help
     
  8. Glenn

    Glenn Kinda grumpy old man Staff Member

    Generally that is all you should need to do.
     
  9. Mr Plow

    Mr Plow Member

    ok, start jeep. Engine heats up at idle and temp gauge goes all the way to H... thermostat does not open. Turn jeep off and start back up again - thermostat pops right open and engine begins to cool as it should. Any ideas what that might mean? Thanks guys!
     
  10. timgr

    timgr We stand on the shoulders of giants. 2022 Sponsor

    Air bubble cleared? Bad thermostat?
     
  11. Mr Plow

    Mr Plow Member

    How do I pop the bubble? Thermostat is 2 weeks old. Could crud from radiator get dislodged and block thermostat weep holes?
    This all happened after changing WP.
     
  12. Glenn

    Glenn Kinda grumpy old man Staff Member

    Did you pull the outlet housing off and check the thermostat? It certainly is possible for crud to block the weep hole if there is one. Can you pull the thermostat out and post a picture of it for us?
     
  13. Mr Plow

    Mr Plow Member

    Will do, gotta run out for a bit but will post soon... Thanks!
     
  14. Mr Plow

    Mr Plow Member

    here is what I have...
     

    Attached Files:

  15. Glenn

    Glenn Kinda grumpy old man Staff Member

    There should be a weep hole noticeably visible from the top when looking straight down at it. I don't see one but the picture isn't looking straight down at it either. If there isn't one just drill an 1/8th" hole through the flat part/flange and that should cure the problem.
     
  16. Mr Plow

    Mr Plow Member

    No there wasn't. So this only lets a trickle through to help 'alert' the stat to pop? Thanks for the info!
     
  17. Glenn

    Glenn Kinda grumpy old man Staff Member

    That is pretty much it. Lets enough flow through there to let the temperature equalize and helps eliminate any air pockets. Also the thermostat should open and close smoothly/progressively.
     
  18. Mr Plow

    Mr Plow Member

    Well I think that worked... I ran the jeep for a good 30 minutes the block temp did not climb past 3/4 and the upper temp (aftermarket gauge) did not go past 190.
    Thanks for the help!
     
  19. Glenn

    Glenn Kinda grumpy old man Staff Member

    I love it when a plan comes together!