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Fhead Overheating

Discussion in 'Flat Fender Tech' started by 73 cj5, Mar 13, 2021.

  1. Mar 15, 2021
    Oldpappy

    Oldpappy A.C. Fults - Curmudgeon at large 2022 Sponsor

    East Tennessee
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    Feb 8, 2021
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    1,620
    I have found strange things in the water jacket of old engines. I found a water logged blackened hickory nut in the engine water jacket on an old Scout II which had spent some years sitting in the woods with the thermostat housing off. Squirrels had also filled the air cleaner housing with nuts. Just wondering if something is inside which only plugs stuff up once the flow increases.
     
  2. Mar 15, 2021
    Glenn

    Glenn Kinda grumpy old man Staff Member

    Apopka, Fl
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    Sep 21, 2002
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    12,367
    I agree with the thoughts about the water jacket being partially blocked, been in my thoughts too. Of course changing the radiator is a much easier option for looking for the problem. Since the radiator condition is more suspect than originally thought a new radiator is certainly the most logical next step.
     
  3. Mar 15, 2021
    ITLKSEZ

    ITLKSEZ Hope for the best, prepare for the worst

    Liberty Lake, WA
    Joined:
    Aug 13, 2015
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    6,656
    If you continue to have issues after the new radiator, I’d get an IR thermometer and check header tube temps, as well as block temps.

    Any chance the muffler is clogged?
     
    OldAdobe likes this.
  4. Mar 15, 2021
    73 cj5

    73 cj5 Not ready for the junkyard yet

    Clinton, Mississippi
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    Jan 10, 2014
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    No muffler.
     
    ITLKSEZ likes this.
  5. Mar 16, 2021
    Greevesman

    Greevesman Member

    Napa, Ca
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    Oct 12, 2014
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    417
    I had a motor, years ago that overheated. The distributor advance weights were stuck in retarded. As soon as I unstuck the weights, it was OK. Not a jeep.
     
  6. Mar 16, 2021
    Rich M.

    Rich M. Shoe salesman 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Maryland
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    Mar 23, 2008
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    Any chance your just running real lean? What do the plugs look like?
     
    ITLKSEZ likes this.
  7. Mar 16, 2021
    jeep2003

    jeep2003 Well-Known Member

    Upstate NY
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    May 30, 2006
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    1,918
    definately check the timing and make sure its advancing properly. If I recall correctly these blocks commonly fill up the water jackets on the bottom and back with rust. You'd have to pull the freeze plugs to clean it out.
     
  8. Mar 16, 2021
    garage gnome

    garage gnome ECJ5 welder

    Western MA
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    Jun 19, 2009
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    3,083
    Or running rich for that matter.
     
  9. Mar 16, 2021
    melvinm

    melvinm Member

    Arvada Co. 80003
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    Aug 11, 2012
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    196
    If the engine has had the cylinders bored over size that can cause the engine
    to over heat ?
     
  10. Mar 17, 2021
    73 cj5

    73 cj5 Not ready for the junkyard yet

    Clinton, Mississippi
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    The radiator arrived today. Little narrower than what was in there and I'm sure with some tabs it could be remounted on the grill. Much better than the old copper/brass stuff.

    [​IMG]

    I took off the old radiator and looked in the tubes. Nasty. A few had junk sticking out of them.

    [​IMG]
    [​IMG]

    I had an M38A1 fan and it is different than my civvy fan. I installed the A1 fan to see if it moves more air?

    [​IMG]

    Since fan shrouds are being used for recovery points now I went ahead and made the radiator mounts out of 3/8" plate. :D I finished just before it started pouring. We have some pretty bad weather coming through right now and our local tornado sirens aren't working so I'll get back to it after the weather passes over.

    [​IMG]
     
  11. Mar 17, 2021
    Fireball

    Fireball Well-Known Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Pullman, WA
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    :rofl:
     
  12. Mar 18, 2021
    73 cj5

    73 cj5 Not ready for the junkyard yet

    Clinton, Mississippi
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    Looks like the new radiator fixed the problem. 13 miles of hard driving and it didn't overheat so I'm convinced the issue is resolved.

    [​IMG]
     
    jeeper50, dozerjim, TuxParkIV and 6 others like this.
  13. Mar 18, 2021
    Fireball

    Fireball Well-Known Member 2024 Sponsor 2023 Sponsor 2022 Sponsor

    Pullman, WA
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    Whoohoo! :bananatool:
     
    73 cj5 and 47v6 like this.
  14. Mar 18, 2021
    73 cj5

    73 cj5 Not ready for the junkyard yet

    Clinton, Mississippi
    Joined:
    Jan 10, 2014
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    I didn't want to stop driving around but I also didn't want to get a ticket for no tag or registration. :whistle: This rattle trap is a blast to drive.
    One day my title will arrive and I can do more testing. :waiting:
     
    dozerjim, 47v6, bigbendhiker and 3 others like this.
  15. Mar 18, 2021
    garage gnome

    garage gnome ECJ5 welder

    Western MA
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    Jun 19, 2009
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    At least it was a simple thing that solved the issue!
     
    Glenn, dozerjim and 73 cj5 like this.
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