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Radiator Hose Valve?

Discussion in 'Early CJ5 and CJ6 Tech' started by GillaFunk, Mar 7, 2021.

  1. GillaFunk

    GillaFunk I'm the Dude, so thats what you call me. 2023 Sponsor 2022 Sponsor

    Question:
    I’m about to install my new summit heater. During summer driving, will the heater core emit heat from the heater if the fan is not on? Or do I install a bypass valve and hose to shut off coolant to the core?
     
  2. FinoCJ

    FinoCJ 1970 CJ5 Staff Member

    I installed a shut off valve after one summer with engine coolant constantly flowing through the heater core in the cab... definitely could feel the heat, especially on the passenger side where mine is installed and my wife rides. With top off and cruising, not too much of an issue, but when sitting in city traffic and with top on, it made the already warm summer temps a bit too much.
     
    GillaFunk likes this.
  3. GillaFunk

    GillaFunk I'm the Dude, so thats what you call me. 2023 Sponsor 2022 Sponsor

    Yup. That makes sense.

    I guess I’ll order some valves

    thanks for your input.
     
    FinoCJ likes this.
  4. kenb

    kenb Cleverly disguised as a responsible adult

    Are we discussing F head applications? One I recently acquired had a remote shutoff of some kind installed. It appears the operator could turn flow to the core on or off from inside the cab. I'm going to need to look again but I think there wasn't an obvious bypass installed when the valve was closed. I wonder if that caused cooling issues for the head.
     
  5. GillaFunk

    GillaFunk I'm the Dude, so thats what you call me. 2023 Sponsor 2022 Sponsor

    yes, F head.
    Yes, my rig came with an in cab knob that actuated a lever to control an in-line valve for the coolant hose. I guess it was a function of the heater? Mine was leaking so I removed it.
     
  6. PeteL

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

    Does yours have the small bypass between the waterpump and the head?
     
  7. kenb

    kenb Cleverly disguised as a responsible adult

    I took a closer look at it. It's a 1962 CJ-5. It is equipped with the 3 pull knob heater control, one of which is a valve on the line to the heater. So when that's closed the flow from rear passenger side of head to water pump is shutoff. It does not have the small bypass on the front (nor is the water pump equipped with a port in that location).
    Interestingly I have another engine that was heater equipped that does have the little bypass on the front.

    I ask because I plan to remove the heater on my M38A1. It's a civilian CJ5 heater with no ducting and the vehicle is never going to have a top. I just want to remove the needless weight and complexity. Right now it has no shutoff. So my options are to run bypass hose where the heater flow used to be (unsightly), run the small front bypass (I think it's equipped but not currently installed), or plug everything.
     
    PeteL likes this.
  8. jeepdaddy2000

    jeepdaddy2000 Active Member

  9. duffer

    duffer Rodent Power

  10. Oldriginal86

    Oldriginal86 Member

    There is ball valves that can be installed in the engine to shut off the coolant flow for the summer or if a leak occurs.