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Technical 351 overheating

Discussion in 'Traditional Hot Rods' started by silversink, Aug 31, 2020.

  1. silversink
    Joined: May 3, 2008
    Posts: 917


    my 46 Ford business coupe is overheating in traffic. 1971 351w-c4-8.8 ford rear-end----Champion radiator 50/50 mix on antifreeze. Timing is spot on and no restrictions in the grill, electric fan set to 190 with a 190 thermostat. When on the move it stays at 190 but stop for a long light and 220-230 degrees are common. I have thick skin ---fire away
  2. sdluck
    Joined: Sep 19, 2006
    Posts: 2,822


    Does it push out coolant"does it have a vacuum advance,is it hooked up.What dist does have in it,what does timing is spot on mean.How big is the eletric fan
    warhorseracing likes this.
  3. Jalopy Joker
    Joined: Sep 3, 2006
    Posts: 27,748

    Jalopy Joker

    post a couple of pics of front of motor, etc
    warhorseracing likes this.
  4. Dave Mc
    Joined: Mar 8, 2011
    Posts: 2,235

    Dave Mc

    Sometimes a Good idea is to "flush the system" before chasing other possible causes
    warhorseracing likes this.

  5. How old is the radiator and when hot is the bottom cores or tank hot also? Could be a partially clogged radiator especially if you have aluminum parts like an intake and are using a sacrificial element in the coolant. Best to show some pictures so we can help.
  6. Ebbsspeed
    Joined: Nov 11, 2005
    Posts: 5,670


    Pusher or puller fan? Fan shroud? Pictures always help.
    warhorseracing likes this.
  7. Deuces
    Joined: Nov 3, 2009
    Posts: 21,627

    from Michigan

    I put a 160° stat in my 351 Windsor.... Nooo problems!.... ;)
  8. George
    Joined: Jan 1, 2005
    Posts: 7,482


    According to info published by Summit, your cyl wall wear will be 3 X higher than if you run a 180-195. If everything is "right" it shouldn't be a problem.
  9. How many pound rad cap do you have?
  10. coupe man
    Joined: Sep 1, 2007
    Posts: 264

    coupe man

    Is the fan wired correctly so it is running in the right direction so fresh outside air is passing through the radiator.
  11. silversink
    Joined: May 3, 2008
    Posts: 917


    no coolant pushing out, new system , puller fan,no shroud,changing therm. today, idle set at 800 rpm. Will get pictures today...…...thanks for all the input so far.
  12. In addition to everything posted above, in hot weather the 1940 Ford needs every possible cubic inch of cooling air coming through the radiator core and not around it. You need a shroud for the fan and all of the side and bottom OEM panels that surround the radiator including an after market piece that fits on the top of the grille if you don't already have them. The top panel helps to get the air through the radiator instead of over the top of it.
    Desoto291Hemi and warbird1 like this.
  13. sunbeam
    Joined: Oct 22, 2010
    Posts: 5,395


    Air flow. Power is heat Running down the road takes more power than sitting at a light. So you must have enough radiator. The car is sitting still do not worry about air coming around the radiator.
  14. FrozenMerc
    Joined: Sep 4, 2009
    Posts: 2,778


    There is a very simple rule of thumb:

    If it overheats idling or sitting in traffic, you need more air flow across the rad and ultimately the engine compartment.
    If it overheats going down the highway you need more radiator.
    waxhead likes this.
  15. jimmy six
    Joined: Mar 21, 2006
    Posts: 10,297

    jimmy six

    If there’s no water moving thru the radiator at idle... all the fans/air in the world won’t keep it cool.
    warhorseracing likes this.
  16. 6sally6
    Joined: Feb 16, 2014
    Posts: 1,799


    I'd try advancing that 'spot-on' timing......running hi-test fuel of course. SBF react very well to a lot of initial timing.
    Adjust carb after bumping up timing.
    Some type of fan shroud or air dam to force air thru rad and not any around it will help too.
  17. Rocky72
    Joined: Nov 22, 2008
    Posts: 205

    from Pa.

    Did you put a serpentine belt on the engine ? If so did you install a reverse flow water pump ? A buddy on mine had the same problem and when I told him to installed a reverse flow pump the problem was gone .
  18. Just changing the water pump can cause restrictions and you will also need to change the timing chain cover. Just changing the back cover from a regular to reverse flow will work but cause a flow restriction. Given your sensitive cooling issue (small grille opening) that may just increase the current problem. I had this same problem on an OT '84 Gran Marquis and had a much larger grille opening so it was a non issue.
  19. Apache Albert
    Joined: Nov 8, 2018
    Posts: 83

    Apache Albert

    Sounds like an air flow issue more so than internal restriction. If you're able to drive with out issues, the water pump is working. Granted it is turning at a higher rate = great fluid flow.

    You're running an electric fan so make sure it can switch from low to high speeds. Also, make sure there are the radiator side skirts or a shroud. I'd think it wouldn't be as applicable because the electric fan should be mounted almost on top of the radiator.

    Finally, try running the car without the hood. Too many times we care about air flow into the engine bay, we forget that it has to go somewhere!


    Sent from my SM-G960U using The H.A.M.B. mobile app
  20. scrappybunch
    Joined: Nov 16, 2011
    Posts: 359

    from nj

    Another + for vacuum adance and connected to manifold vacuum.
    Fixed the "unfixable" overheating 37 ford sbc by adding advance pot to distributor. That was after he spent 1000's on everything else.
  21. partssaloon
    Joined: Jan 28, 2009
    Posts: 519


    I'm running basically the same thing, 351+.040, C4, 9 in. I have a Madson radiator (called Fanman now). Mechanical fan W/shroud, pusher electric in front of the condenser (only use it when the A/C is on). 180 thermostat. In the winter it is all I can do to get it to 180. In the summer (122 today) with the A/C on it might go to 200
  22. big bird
    Joined: Feb 16, 2014
    Posts: 101

    big bird

    Did you change the thermostat?
    Cleveland 351 takes a weird thermostat with a little hat on the bottom that closes a bypass when it opens.
    Is the engine a recent rebuild? the thermostat hat fits into a brass plate with a corresponding hole. Not unheard of to forget to reinstall after a rebuild/hot tank.
    Edit: never mind i thought you said it was a 351C, caught the "C' from the C4
  23. OP told us Tuesday he would be back with pictures and has not been back since. Pictures would help identify a shroud or lack thereof and so much more.
    Desoto291Hemi likes this.
  24. Welcome to Crystal Ball Diagnosis Service.
    waxhead and warhorseracing like this.

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