Midwest Classic Insurance

Visit our community sponsor

Thanks Thanks:  0
Likes Likes:  0
Results 1 to 4 of 4

Thread: Cooling question

  1. #1
    Junior Member
    Join Date
    Jan 2019
    Location
    Mandeville, LA
    Posts
    24
    Post Thanks / Like

    Cooling question

    I have a 351w with first start today. Felt great.

    It gets hot within a few minutes of starting and the radiator fan seems to kick on too late. I have 180 thermostat and it’s about 70 degrees outside here today with the car sitting.

    What temperature is the fan supposed to kick on?

  2. #2
    BadAsp427's Avatar
    Join Date
    Jul 2018
    Location
    Greeneville, TN
    Posts
    1,177
    Post Thanks / Like
    That will depend on the switch you have installed. The one that came with my kit came on at 180, but the thermostat is a 180. This caused my fan to come on and stay on all the time... I replaced the switch with one that comes on at 200 and off at 185 this way the thermostat and ram air will keep it cool as I'm driving it but when standing still, the fan can and does do it's job. I picked mine up from HERE for $8.00.

    Mk4 20th Anniversary #8690 (#8 of 20) Purchased 8/18/18----Build Started 8/19/18
    Build Thread Click Here / Registry Entry Click Here / BluePrint Engines 347ci / TKO600
    Carb/Heater/Heated Seats/Cruise Control/Drop Trunk & Battery/Custom Cubby

  3. #3
    Seasoned Citizen NAZ's Avatar
    Join Date
    Feb 2016
    Location
    "The High Country", beautiful Flagstaff, AZ
    Posts
    2,443
    Post Thanks / Like
    How hot is too hot? If you have a 180-deg t-stat what running temp are you expecting? What high limit will you accept? What temp do you want the fan to kick on / off? And make sure your recovery tank is sized correctly & the pressure cap is rated for the pressure for your desired operating temperature. Your coolant will expand and contract with temperature and unless you have an expansion tank or leave enough room in the radiator coolant will puke into a recovery tank. The more temp variation the more expansion -- and this can be calculated so you don't have to guess at the size tank you need.

    A t-stat is usually rated at the temp it starts to open and may fully open 10-15 degrees above that. If you're not sure what you have you can easily check the actual fully open temp and the fan switch open / close temps by placing them in a pan of water with a thermometer on your stove and slowly bring up the heat. Use your ohm meter on the switch to determine when the switch is open (off) and closed (on). You can visually see the t-stat open and close.
    Dart Little M 406" SBC 800 HP N/A & 1,100 HP on nitrous, 2-spd Powerglide with trans brake, 6,000 RPM stall converter, narrowed Moser 88 3.90:1 spool with 35-spline gun-drilled axles & Torino bearings, custom parallel four-link, custom tube chassis & roll cage NHRA certified for 8.5-sec (only two FFR Hot Rods have this cert).

    33 Hot Rod Super Pro Drag Racer Build: 33 HR NHRA Cert Roll Cage Build

  4. #4
    Senior Member Avalanche325's Avatar
    Join Date
    Nov 2011
    Location
    Jax Beach, FL
    Posts
    2,103
    Post Thanks / Like
    Getting hot, not just warm, within a few minutes? That is an indication of air in the system.

    Where are your sensors located?
    What is your definition of that fan kicking on too late? Mine takes a long time before it comes one from startup.
    Do you see coolant flow when the temp comes up with the cap off? I always test new thermostats.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  

Breeze

Visit our community sponsor