Register now to get rid of these ads!

Technical 383 sbc 235° @ 65mph 200° @ idle

Discussion in 'Traditional Hot Rods' started by Jchill40, Jun 22, 2020.

  1. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    383 w/ turbo 400 trans. 2200 cfm cooling fan runs full time pushing. Good 3 row radiator. Car was built in western Colorado. Had high temp issues at the start that the pusher fan fixed immediately. @80mph on Highway it runs 190-205° consistent for very long cruises.

    Moved to Central Texas car run 230° +/- at hi way speeds of 60-70 mph , at idle and <30 mph will cool to 200-205. This is measured driver side head. Also I ran 2nd temp @intake , 15-20° cooler except at 65 + mph for any cruise over 20 minutes will heat up to 220° at intake and 240° at head.

    I have adjusted timing. I have re jetted carbs to recommended (triple deuce-Rochesters w/ progressive linkage set up from Vintage Speed). Replaced cooling fluid to Evans waterless. I’ve played with fuel mixture. Plugs are more grayish telling me it’s too lean but I’ve played with full range of the mixture/idle screws with no luck.

    Any ideas? Appreciate the input

    View attachment 4730393


    Sent from my iPhone using The H.A.M.B. mobile app
     
    Last edited: Jun 22, 2020
  2. The pusher fans are known to block airflow to the radiator at all engine speeds. A good quality fan behind the radiator WITH a shroud covering the entire radiator would be where I would start.

    What thermostat are you running?

    Phil
     
  3. brigrat
    Joined: Nov 9, 2007
    Posts: 5,157

    brigrat
    Member
    from Wa.St.

    What car/truck is it in?
    Sounds like air is going around the radiator instead of threw it @ speed...………...
     
    MAD MIKE and Jchill40 like this.
  4. gene-koning
    Joined: Oct 28, 2016
    Posts: 1,816

    gene-koning
    Member

    Do you have a trans cooler (or AC condenser) mounted in front of the radiator? When was the last time you hosed out the radiator fins? Could be dirt/stuff between the coolers and the radiator reducing the air flow. Overheating on the highway, then cooling down in town, is a classic example of an air flow through the radiator blockage at speed. Its also possible the air hitting the front of your ride is going around the radiator rather then through it at highway speeds. Its also possible the air that has passed through the radiator can't get out of the engine compartment at highway speeds.

    Your overheating could be a trans overheating issue (trans slipping at highway speeds) that is adding an extra burden to the motor cooling system.

    The idle adjusting screws won't have any effect on the air/fuel mixture above an idle. If you think its still running lean, you need bigger jets inside the carb.

    240 is pretty hot, you might want to look into an additional oil cooler. That would probably help the motor temp a bit. Gene
     
    olscrounger and Jchill40 like this.
    Register now to get rid of these ads!

  5. 1934coupe
    Joined: Feb 22, 2007
    Posts: 3,914

    1934coupe
    Member

    Another first post. Show some pictures, what car/truck is it in and pusher fans are last in rank on cooling systems.

    Pat
     
  6. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    61341595562__E2EBF3C1-F610-4D84-813D-0429C35C2863.JPG

    Pusher was necessary for lack of room for puller or a flex fan. Picture hopefully attached this time. I maybe made a mistake adding it in original post



    Sent from my iPhone using The H.A.M.B. mobile app
     
    Tim likes this.
  7. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    Appreciate the reply. Original post I thought had a picture, guess not. Pusher solved the problem in Colorado. A 220 mile cruise in 90° temps in Colorado the day before I hauled it to Central Texas. Temp never got over 200°. Since I’ve been here in Tx can’t keep it under 230° at hiway speeds.

    61341595562__E2EBF3C1-F610-4D84-813D-0429C35C2863.JPG


    Sent from my iPhone using The H.A.M.B. mobile app
     
  8. blowby
    Joined: Dec 27, 2012
    Posts: 6,589

    blowby
    Member
    from Nicasio Ca

    This guy did a test of push vs pull fans. 15 minutes long but I found it interesting.

     
    Jchill40 likes this.
  9. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    Super clean in the fins. I did spray them down and got little to no noticeable debris or dirt. Car does have AC and the condenser is on the inside between engine and radiator. All was the same in Colorado, 220 mile cruise in 90°temps never had temp over 200°. No changes made to car but trailer it to Tx and it’s 230° at hi way speeds and I’ve not been able to solve it. Roughly 1500 miles on the new engine when I left Colorado and 2000 +/- miles on it now.

    61341595562__E2EBF3C1-F610-4D84-813D-0429C35C2863.JPG


    Sent from my iPhone using The H.A.M.B. mobile app
     
  10. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    1930 Model A
    Pic attached. 61309818979__F80951D5-EE02-41B4-A12C-738452A45D05.JPG


    Sent from my iPhone using The H.A.M.B. mobile app
     
  11. Budget36
    Joined: Nov 29, 2014
    Posts: 3,455

    Budget36
    Member

    Try shutting the fan (s) off at highway speed.
     
    Jchill40 likes this.
  12. jaw22w
    Joined: Mar 2, 2013
    Posts: 1,009

    jaw22w
    Member
    from Indiana

    I don't know where in Colorado you were, but it sounds like a lot of elevation change. I suspect a jetting problem. The air got denser in Texas.
     
    JC Sparks, Tim, kevinrevin and 2 others like this.
  13. greybeard360
    Joined: Feb 28, 2008
    Posts: 1,459

    greybeard360
    Member

    Short or long water pump?

    I can't see the front mounted fan but seeing what I can, it looks like the radiator could be moved forward in the radiator shell. If you are using the long pump put the short one on it with correct pullies and make room for a real fan. If needed pu
    t the a/c condensor under the back of the car with the pusher fan on it. That is how my brothers model A is done.

    Welcome to Texas where it get warm in the summer..... you haven't seen the heat yet!!
     
    Baumi, belair, 427 sleeper and 2 others like this.
  14. Good as in good used? I find it hard to believe that it won't stay cool out there in the open as it is. Have you checked for hot spots any where on the core?
     
    Jchill40 likes this.
  15. trollst
    Joined: Jan 27, 2012
    Posts: 1,724

    trollst
    ALLIANCE MEMBER

    I see blue headers, all the way to the back, you're pushing a ton of heat out the exhaust, and in my opinion, WAY more than you should. There's got to be a lot of fire going into those pipes, in an open hood car, you shouldn't have that kind of heat, Start with timing, I agree the pusher fan is bad, they block a ton of airflow, but somethings wrong with your setup, the headers show it, even under a tight hood and side panels you shouldn't have that kind of heat.
     
    Baumi, F-ONE, big duece and 7 others like this.
  16. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    Jets were changed. Not immediately as I had to order them but no temp change occurred after the correct jets were put in.


    Sent from my iPhone using The H.A.M.B. mobile app
     
  17. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    Good as in brand new, 300$ aluminum. Reputable eBay seller. Car never got over 200° in Western Colorado, Grand Junction area.


    Sent from my iPhone using The H.A.M.B. mobile app
     
  18. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    You bring up things I’ve noticed myself. I’m struggling because no changes were made to this car from CO to here in TX. 200° in CO , 230° in TX both on 90° days. Timing is 14° @ 2800rpm. I’ve set it from 11° - 18° with no noticeable change in temp. The AC condenser under the rear is a new thought? I like it. Short water pump is on now, I’ve given thought to a high flow pump next.


    Sent from my iPhone using The H.A.M.B. mobile app
     
  19. gene-koning
    Joined: Oct 28, 2016
    Posts: 1,816

    gene-koning
    Member

    Interesting. What is the temp (and humidity) difference in Texas compared to Colorado?

    I'm going to say you have more air going around your radiator then is going through it. It could be as simple as the difference in the speed at which you were driving.

    One of the big issues with a pusher fan is they tend to block or deflect air flow through the radiator and it gets worse as the car is moving. The fan blades spin at a specific rpm. If the fan speed matches up to the amount of air that is traveling through the rad, or the fan is pushing more air then what would be blowing through the rad without a fan, things are usually good. The problem occurs when the fan is moving less air then would be blowing through the radiator with out a fan. The blades on the fan act like a circular disc and will slow down the amount of air that can pass through. This effect tends to create a higher temp at highway speeds because of the reduced air flow. The biggest problem is the pusher fan is creating the blockage in front of the radiator.

    The only explanation as to why it didn't make as much difference in CO is maybe the highway speed. The extra speed in CO may have forced enough air around the fan blades to reduce the fan blade blocking effect.

    Puller fans, being mounted behind the radiator can also block the air flow through the radiator, but since the air has already passed through the radiator, all the air needs to do it get around the fan blades. Most of the time, the spacing between the fan blades and the radiator on a puller fan is large enough to allow the air that has already passed through the radiator to get around the fan blades. Of course the air flow is still impeded by the fan blades, but it will allow more air to pass through, maybe enough extra air to lower the water temp.

    This all can go out the window if the puller fan has a close fitting fan shroud. Ideally, a puller fan (electric or mechanical) will have a shroud that fits the radiator well and fits the fan well, and then may have flapper doors that can open if the wind can pass more air then the fan can pull.

    Engine mounted fans tend to pull more air the faster they spin, so when the engine rpm is higher, the fan speed is higher and more air is being pulled through the radiator. Normally a mechanical fan with a shroud will have 1/2 the fan blade in the shroud and 1/2 out of it, thus creating space for additional air to pass through the radiator if the fan is not pulling air as fast as the air would flow without a fan. The purpose of the shroud is to make sure the fan pulls more air through the radiator at lower engine speeds.

    On your car, I would remove the pusher fan, relocate the AC condenser to in front of the radiator and mount either a puller electric fan, or a mechanical fan on the engine side of the radiator. I know its that is a lot of work, but I think it will solve your problem. Gene
     
  20. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    It’s worth a shot. Though this was my high temp fix in Colorado. I’m open to any ideas I feel I’ve hit a wall


    Sent from my iPhone using The H.A.M.B. mobile app
     
  21. Budget36
    Joined: Nov 29, 2014
    Posts: 3,455

    Budget36
    Member

    I know it's not a direct comparison due to design and fan placement, but factory cars with electric fans usually shout them off around 35-40 MPH.

    Good luck.
     
    Desoto291Hemi and Jchill40 like this.
  22. Budget36
    Joined: Nov 29, 2014
    Posts: 3,455

    Budget36
    Member

    RE: Co. V Texas, you probably are running leaner now due to elevation change, pretty sure it was mentioned before.

    How do the plugs look?
     
    ottoman, raven and Jchill40 like this.
  23. trollst
    Joined: Jan 27, 2012
    Posts: 1,724

    trollst
    ALLIANCE MEMBER

    Well, you shouldn't have blue headers, my 327 has camel hump heads, flat top pistons, a 300 horse cam, goes like a stuck pig in my 2770 pound 36 pickup, headers are painted with stove paint, and have never discoloured. I run a full hood, on your car, my headers would burn off in five minutes. Get yourself an infrared temp gun, start going over where the heat is coming from, and I'd do what I had to, to get rid of that pusher fan.
     
    Jchill40 likes this.
  24. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    Do you feel a heavy duty flex fan would perform better over electric fan ? Increased speed should increase air flow pulled with a flex fan In theory? Electric would be constant?


    Sent from my iPhone using The H.A.M.B. mobile app
     
  25. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    Grayish. Definitely looks lean. But I’ve re jetted now. It Didn’t fix temp issue.


    Sent from my iPhone using The H.A.M.B. mobile app
     
  26. Jchill40
    Joined: Jun 22, 2020
    Posts: 15

    Jchill40

    Thank you Sir! Sincerely


    Sent from my iPhone using The H.A.M.B. mobile app
     
  27. MAD MIKE
    Joined: Aug 1, 2009
    Posts: 489

    MAD MIKE
    Member
    from 94577

    We need to make cooling great again. Build that wall.
    He's right.
    If you look at your grille/rad pic you can see past the rad and I see the frame rail...
    [​IMG]

    At speed the air is going to find the path of least resistance.
    It's not going to go through the radiator, it's going to go around it.
    Air is hitting the rad, stopping and going around the radiator.
    You need to block off the opening between the grille shell and the radiator.
    It needs to be funneled into the radiator, otherwise it will go around the radiator and not cool.

    That is what is happening at speed.
     
    Cosmo49, i.rant, ottoman and 4 others like this.
  28. NelsonN
    Joined: Sep 13, 2019
    Posts: 3

    NelsonN
    ALLIANCE MEMBER

    Check the lower hose going into the radiator is it soft is it collapsing? I could not find a lower hose with a spring in it to put on my hot rod. The hose is 2" OD I was able to slide a 1 3/4" piece of Stainless exhaust pipe thru a bend an into a straight section. It worked, make sure you file any rough ends, use a few drops of silicon to make the slide easier.
     
    bchctybob and Elcohaulic like this.
  29. Do you have the vacuum advance hooked up and if it is, is it hooked to manifold vacuum?

    Sent from my Nexus 5X using The H.A.M.B. mobile app
     
    deathrowdave and x77matt like this.
  30. Are you sure it only has 14 degrees of advance at 2800 rpm? At that engine speed you should have 34 to 36 advance.

    Is mechanical advance free so it can add to your initial advance? In addition is vacuum advance working?

    Lack of ignition timing can cause heat from unburned fuel being pushed out headers.


    Phil
     
    Last edited: Jun 22, 2020

Share This Page

Register now to get rid of these ads!

Archive

Copyright © 1995-2020 The Jalopy Journal: Steal our stuff, we'll kick your teeth in. Terms of Service. Privacy Policy.

Atomic Industry
Forum software by XenForo™ ©2010-2014 XenForo Ltd.