Welcome to Our Community

Wanting to join the T-Bucket Forums discussions? Then sign up for a free forum account, today!

Sign Up

Ron Pope Motorsports                California Custom Roadsters                Spirit Industries                Southern Legacy Freight!               


Dismiss Notice
Thank you for visiting the T-Bucket Forums! This site was created in 2006, to provide enthusiasts with a place to discuss T-Buckets. Over the years, there have been many imitators, but this is the T-Bucket resource you have been looking to find. We encourage you to register a FREE account and join in on the discussions.

Cooling secrets

Discussion in 'T-Bucket Engine and Driveline Articles' started by PotvinGuy, Oct 7, 2016.

  1. PotvinGuy

    PotvinGuy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2008
    Messages:
    1,465
    Likes Received:
    336
    Gender:
    Male
    Occupation:
    Quantum Mechanic (semi-retired)
    We’ve all heard the usual advice about beefing up our rod’s cooling system. Bigger radiator, more air flow, more water flow, etc. All good things, but, before you lay out any big bucks, read on. When I built my rod it was prone to overheating, and in the course of taming it I discovered these cooling secrets. But first let’s define overheating in the context of this article. Overheating: the coolant temperature rises relentlessly, and steam and boiling water spurt from the overflow line. It is not simply a “hot” temperature. You may not like it that your rod runs at 230F, but as long as it can stabilize at some temperature, it is not overheating as used herein. That said, the secrets in this article can also lower your temperature if you so desire. Now the propensity to overheat is a function of variables, some of which are fixed in the engine design, and some of which we can control. Four variables we can control are 1) coolant composition, 2) coolant system pressure, 3) coolant flow, and 4) air flow, and we will explore how to manipulate these to eliminate overheating.


    But before we start, check your timing. I’ve seen many a motor running hot because the timing was retarded. A small block Chevy should be running at least 15 degrees before TDC at idle. Mine idles at 35 degrees BTDC and purrs like wifey after a box of wine.


    On to secret #1: did you know that water is a better coolant than antifreeze? And the clichéd 50/50 mix is not the optimum mix for many of us? You actually need only enough antifreeze in your water to ensure the coolant doesn’t freeze at the coldest temperature your car will encounter while it is sitting and the engine has cooled to the ambient temperature. Now when I lived in Texas and my rod sat in the garage, I didn’t need any antifreeze; it never got down to 32F in there. So I ran straight water. But not just any old water. A restorer of old Jaguars told me he puts distilled water in his cars. See, tap water has minerals that will eventually deposit on the inside of the radiator and the engine, reducing the efficiency of the cooling system. But wait; there’s more. I used Red Line Water Wetter, an additive which lowers surface tension, thereby improving heat transfer. One bottle of it lowered my coolant temperature 5 degrees. And a second bottle dropped the temperature another 5 degrees! Even if you need some antifreeze for your climate, you can add this additive to improve your cooling efficiency.


    Secret #2: Do you know the pressure rating of your radiator cap? Who cares, you say? And why do we need any pressure in the cooling system, anyway? A little physics: the boiling point of any liquid increases with pressure. So the higher the pressure, the less the chance of coolant boiling into steam in the hottest places in the engine, namely around the combustion chambers. Now steam is a lousy coolant and is impossible to pump, and once you get a little of it, the hot spots can get hotter and make more steam and you have runaway overheating, which is serious business (engine damage) and you better get parked pronto. Luckily, caps are available in many pressure ratings, from 7lbs to nosebleed, and you might want to experiment with higher pressure caps. But be careful: use the lowest pressure cap that will do the job, because higher pressure puts more strain on hoses, gaskets, and the radiator itself. Be alert for leaks if you increase your pressure. And get an overflow tank if you don’t already have one. With the system full, as the coolant and any air in the system heats and expands, some coolant will go into the tank. Then once the engine is off and cooling down, this coolant will be sucked back into the system. Without a tank, you will lose some of your coolant and the system won’t be as effective as it would be if it were completely full. And make sure these is always some coolant in the tank; if the tank is ever dry, then the system will be sucking some air. You need a bigger tank if it continues to run dry. And note that coolant overflow increases with increasing temperature, so the tank must be sized for the highest temp you will encounter. When in doubt, go big.



    Secret #3: Coolant flow rate: an old rodders tale says if coolant flows too quickly through the radiator it will not have time to cool “properly”. But if you keep the coolant in the radiator longer, it also stays in the engine longer, which increases coolant temperature. Coolant in the engine can literally boil away from the hot spots if not forced through the cooling system at a high enough flow rate. This is one area where more is always better. High-flow water pumps are an easy install and can add to your peace of mind.



    Secret #4: Air flow. Let’s talk fans. Conventional mechanical fans are fine if they are doing the job, but one or two electric fans can help in nail-biting airflow situations, like sitting in summer traffic jams. I don’t have a thermostat (which is a story for another time), so to modulate my coolant temperature the two pusher electric fans on my radiator are connected to a Painless Wiring fan controller. This nifty little gadget controls the speed of the fans. You set a temp for the fans to come on at half-speed, and a temp for them to be at full speed. The controller ramps up the fan speed in sync with coolant temp. This keeps my engine at a stable temp regardless of air temp or engine load. And Dakota Digital has a controller for two fans with adjustable on and off temps for each fan. I have used it with success too. I also have an electric water pump and I wired it so the pump runs along with the fans for a minute after key-off to cool things down a bit. If a controller is not your cup of tea, electric fans can also be controlled by simple thermostatic switches and/or manually with a dash switch.


    And that’s it. I’m assuming your thermostat (if you run one; trust me, it’s not mentioned in the Ten Commandments) is working, and your radiator is spotless inside; if you have any doubt, pull it and have the local radiator shop clean it. Then optimize your coolant as described and make sure the system stays full with a properly sized overflow tank. If you’re still overheating then try a higher-pressure radiator cap and/or add electric fans and a high-flow water pump. And check your timing!


    I’ll be delighted to hear from you; contact me at dr.kerrysmith@gmail.com with any comments or questions. I don’t have all the answers, but I will pretend I do.
     
  2. choppinczech

    choppinczech
    Expand Collapse
    Active Member

    Joined:
    Jul 2, 2012
    Messages:
    828
    Likes Received:
    319
    Gender:
    Male
    Occupation:
    Maintenance
    :thumbsup::thumbsup::thumbsup: I like that.
     
  3. Gerry

    Gerry
    Expand Collapse
    Active Member

    Joined:
    Dec 31, 2009
    Messages:
    2,391
    Likes Received:
    322
    Gender:
    Male
    Whats your thoughts on waterless coolant, such as Evans. I am going with this due to feedback from a few guys who use it in quite strenuous situations. As the block is bone dry and the rad is new I dont have to do the flush to get all the moisture out.

    I also made the rad cap and that is adjustable with a nut.
    Many years ago I was in contact with a guy in the USA who was knowledgeable on 350 Chevy cooling. He worked out the rad configuration for me and thats what I went for. 5 Row, minnow fish finning.

    feb10 (17) (2015_11_13 11_07_31 UTC) (Copy).JPG
    feb10 (10) (2015_11_13 11_07_31 UTC) (Copy).JPG
    feb10 (18) (2015_11_13 11_07_31 UTC) (Copy).JPG
     
  4. Spanky

    Spanky
    Expand Collapse
    Well-Known Member

    Joined:
    Jul 29, 2016
    Messages:
    1,561
    Likes Received:
    711
    Gender:
    Male
    My brother, who lives in Florida, uses just distilled water and about 3-4 ozs of Marvel Mystery Oil :) in his blown 351 Ford-powered T-bucket.
     
    Snicklefritz likes this.
  5. PotvinGuy

    PotvinGuy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2008
    Messages:
    1,465
    Likes Received:
    336
    Gender:
    Male
    Occupation:
    Quantum Mechanic (semi-retired)
    I haven't tried it, but my understanding is that it has a high boiling temp, so your motor might run at, say, 250F, and not boil over. But I wouldn't want my motor to run that hot.
     
  6. Cole Luke

    Cole Luke
    Expand Collapse
    New Member

    Joined:
    Mar 8, 2019
    Messages:
    13
    Likes Received:
    0
    Gender:
    Male
    Dr. Smith, my radiator has a few pin holes so I'm looking to replace it. I just got the car from my father (heirloom) and I'm a bit of a novice. I know in the past it has liked to run between 200F and 220F. It has an electric fan with a simple dash switch and a reservoir "tube". I live in TX so the summer's get hot meaning I want to be sure to have enough cooling. I use a 50/50 premixed solution currently, but obviously adding a lot often due to the pin holes. Do you have any recommendations, suggestions, tips, etc. to graciously provide? Best place to purchase one? I don't know anything about the cap/pressure, coolant flow, or air flow but can look around if it helps. Thanks!
     
  7. HenrysT

    HenrysT
    Expand Collapse
    Member

    Joined:
    Mar 12, 2012
    Messages:
    400
    Likes Received:
    90
    Gender:
    Male
    Occupation:
    Carpenter
    NOT Dr. Smith but what do you have now? Brass, aluminum? Core size? Pics?
     
  8. Guy

    Guy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2019
    Messages:
    387
    Likes Received:
    79
    Gender:
    Male
    Occupation:
    kinda Retired
    What dose he use for a thermostat, I noticed mine doesn't have one when the engine was torn down
     
  9. PotvinGuy

    PotvinGuy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2008
    Messages:
    1,465
    Likes Received:
    336
    Gender:
    Male
    Occupation:
    Quantum Mechanic (semi-retired)
    Cole, I built my bucket in Dallas and lived there until 2010. My cooling secrets came from my experience in TX summers. Before you buy a new radiator you might try some Stop Leak. If you want a new one, I got mine from Dallas Radiator which I think is still in business. I gave them a sketch with dimensions and the fittings I wanted. A totally custom job.

    For coolant I used distilled water and two bottles of Red Line Water Wetter. You don't need antifreeze, and water is the best coolant. I would add an overflow tank so the radiator is always full. And a thermostat switch or other fan controller so you don't have to watch and turn on the fan. The fan should be a puller if it is on the back side of the radiator. Cap pressure..I used to run 13# in summer and 7# in winter. The added pressure in summer raises the boiling point. I ran around 220 all summer without problem. I see you have a blower which makes the motor hotter. You might consider underdriving it.

    Ordinary water pump should be OK, but a high flow one is a plus.

    Try some or all of these and let us know how it works.
     
  10. 2old2fast

    2old2fast
    Expand Collapse
    Active Member

    Joined:
    Mar 25, 2010
    Messages:
    2,338
    Likes Received:
    483
    Gender:
    Male
    Occupation:
    sorta retired
    DOSE is like you have a "dose" of the clap
    DOES means he "does" go to work ...
     
    Neshkoro likes this.
  11. old round fart

    old round fart
    Expand Collapse
    Well-Known Member

    Joined:
    Feb 5, 2008
    Messages:
    2,429
    Likes Received:
    556
    Occupation:
    Retired
    Kerry, I’m planning on the radiator in the bed. How thick is your core and how big is it? Thinking about 4” aliminum core or more than one radiator. May use a 30” pick up bed. I’ll have a blown 454. Wish you were still in Dallas! Lol
     
  12. Cole Luke

    Cole Luke
    Expand Collapse
    New Member

    Joined:
    Mar 8, 2019
    Messages:
    13
    Likes Received:
    0
    Gender:
    Male
    I'm not sure. I'll dig around to see if I can find anything. I can certainly take some pics.
     
  13. Cole Luke

    Cole Luke
    Expand Collapse
    New Member

    Joined:
    Mar 8, 2019
    Messages:
    13
    Likes Received:
    0
    Gender:
    Male
    Thank you sir. I'll pick up some wetter as soon as I stop the leaking. I do have an overflow tank, but I recall my grandfather saying to never open it. I was thinking that was maybe because it was mounted lower than where the water level would be in the radiator, but not sure that holds any weight??? I also did some research and looks like there are specific T-bucket radiator offerings on speedwaymotors.com and jegs.com. Anyone ever buy anything on those sites?
     
  14. PotvinGuy

    PotvinGuy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2008
    Messages:
    1,465
    Likes Received:
    336
    Gender:
    Male
    Occupation:
    Quantum Mechanic (semi-retired)
    OK to open the overflow tank after the motor has cooled down. When the motor is warming up, expanding coolant will be flowing into the tank. When the motor is off and the temp drops the radiator will be sucking coolant back. If you use a clear hose you can see this happen. I always check my tank to make sure it's not empty; if it is the radiator will be sucking air. The whole point of an overflow tank is to ensure the radiator is always completely full. Some folks just run the hose to the ground and that's OK if you don't have temp problems. But in TX summers I didn't take any chances. Real OCD.

    Speedway and Jegs are good vendors, I've bought from them for many years. Also check CCR (click on their logo at the top of the page here). They've been in the T-bucket business since the first caveman made a rock wheel. I have a CCR body and windshield.
     
    Spanky and Cole Luke like this.
  15. PotvinGuy

    PotvinGuy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2008
    Messages:
    1,465
    Likes Received:
    336
    Gender:
    Male
    Occupation:
    Quantum Mechanic (semi-retired)
    2.5" thick, 33" wide (not including end tanks), 12.5" tall. Copper/brass.
    [​IMG]
     
    lincolnuT and Spanky like this.
  16. old round fart

    old round fart
    Expand Collapse
    Well-Known Member

    Joined:
    Feb 5, 2008
    Messages:
    2,429
    Likes Received:
    556
    Occupation:
    Retired
  17. 2old2fast

    2old2fast
    Expand Collapse
    Active Member

    Joined:
    Mar 25, 2010
    Messages:
    2,338
    Likes Received:
    483
    Gender:
    Male
    Occupation:
    sorta retired
    Potvin guy , are you talking about a surge tank ? The only time coolant flows into a return tank is when system pressure exceeds cap rating (overly high temperature ), then flows back to the rad. when cool via system vacuum ..
     
  18. PotvinGuy

    PotvinGuy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2008
    Messages:
    1,465
    Likes Received:
    336
    Gender:
    Male
    Occupation:
    Quantum Mechanic (semi-retired)
    Yes, same thing. If the cooling system is completely full, then system pressure will exceed the cap rating as the water warms and expands, and water will go into the tank. But if there is some air in the system (which is common), little or no overflow may occur. The amount of overflow, if any, depends on how much air is in the system, the water temperature and the capacity of the cooling system. My full system holds 3.5 gallons (~ 450 oz) and at 220° will overflow around 0.16 gallons (20 oz). Being a bit OCD I have a 35 oz overflow tank. :geek:
     
  19. PotvinGuy

    PotvinGuy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2008
    Messages:
    1,465
    Likes Received:
    336
    Gender:
    Male
    Occupation:
    Quantum Mechanic (semi-retired)
    ....and I keep some water in the tank when cool, as some hot water will be lost by evaporation out the tank port. I don't want to alarm anyone; my setup is not the norm. Most folks have some air in their system and run well below 220°. A typical T might not even have an overflow tank, but just run the tube to the ground. Checking the water once in a while and adding if needed does the trick for many.
     
  20. Guy

    Guy
    Expand Collapse
    Supporting Member
    Supporting Member

    Joined:
    Feb 22, 2019
    Messages:
    387
    Likes Received:
    79
    Gender:
    Male
    Occupation:
    kinda Retired
    I am getting near the end with my T if there is an end, I only have 3" between the new radiator and the center pulley will I be able to run a fan or do I need more room I don't see many specs for them not sure how wide they are front to back ? Any information will be appreciated Guy
     






Advertise with Us! Advertise with Us! Advertise with Us! White Rose Technology Ting Mobile Buy VPN


SSL Certificate