What is likely damage from overheat under power?

Discussion in 'Race 400/430/455' started by BQUICK, Sep 18, 2017.

  1. BQUICK

    BQUICK Gold Level Contributor

    Was rushing Saturday at Cecil in the JAG and forgot my water pump and made a full pass with no pump.
    Noticed on return road, thought gauge needle fell off but it was wrapped all the way to the back side of the pin! 280+!!!Puked water into overflow.
    Turned pump and fan on and it cooled right off.

    What would first damage be? I have aluminum Stage 1 SE heads, half block fill and aluminum rods (GRP)
    I changed the oil and it looks fine. Going to retorque heads and go over valves today.

    It must have detonated with that much heat......
     

    Attached Files:

    Last edited: Sep 18, 2017
  2. Jim Weise

    Jim Weise EFI/DIS 482

    Most likely damage is piston skirt scuffing, followed by piston rings loosing their tension.

    Detonation?.. maybe depends on what fuel your using, and how close it is to the "edge".

    Symptoms will be the car slowing down, excessive blow by and oil leakage from a pressurized crankcase, if you really hurt it.

    Beyond that, the valve guides probably got scuffed, but you didn't stick an exhaust valve, consider yourself lucky..

    You cooked every gasket in the motor.. all are now somewhat more brittle than before..

    Hopefully you just scuffed the piston skirts a bit, which might cost you a set of pistons at your next freshen up, and nothing else serious happened.

    Years ago I bought one of the first backhalved 81 up body style Regals from Dan Hopkins. It had the typical switch panel. After a couple trips to the drag strip, and having to turn several switches on an off every time I started the car, Bucy and I thought there has to be a better way to do this.

    So we designed a system that employs a high amperage Electric Golf cart solenoid, that cuts the main power feed, with the flip of a switch. The solenoid is in the trunk, next to the battery.. so everything forward of that is dead, so no worries about shorting anything out, while your working on it.. also, when cooling between rounds, the only switches on are the main switch, the water pump and fan.. when your down to temp, you just flip the main power switch..

    When you start back up, fan and water pump are already on.. I typically would turn the fan off, and set the other switches before I hit the starter button... roll up, get in line, and hit just one switch.. the main, to shut it off.. .then back on with one switch, as we moved forward in line... and one switch to start it to make the run...

    I still see guys flipping all kinds of switches every time they start the car to move it 10 feet.. and I have to chuckle..

    Just an idea for you, to eliminate this from happening in the future. The golf cart solenoids are available at Napa, and not real expensive.

    Never had one fail, thru three cars, and lots of racing.

    JW
     
    Briz likes this.
  3. BQUICK

    BQUICK Gold Level Contributor

    Thanks Jim.
    What about cam bearings?
    Also, didn't do the valve springs any favors. Superheated heads transferred heat right to them, right?
    Should I do a compression test?
     
  4. BQUICK

    BQUICK Gold Level Contributor

    Hopefully this latest incident only used up another of the cat's nine lives......
     
  5. Bens99gtp

    Bens99gtp Well-Known Member

    We wired in a second relay, my fan and pump are on 1 5 pin relay ( only needs 4 pins to make it work ) the magic comes with the 5th pin, this will allow power to flow through to fans and pump with that relay off. The second relay is turned on with the ignotion the output from this relay goes to the 5th pin on relay 1. Easy to turn fan and pump on by switch, and then if I forget it automatically happens with ignotion on.

    I forget the technical term for this type of relay but someone will know it. Whathe I like about this is its not a full rewire of everything, easy add on in very little time
     
  6. Bluzilla

    Bluzilla a.k.a. "THE DOCTOR"

    My Skylark uses a HD three way switch hidden under the dash (still a street car too) pointing down. Center position is off.
    Forward position allows B+ to the thermostatically controlled 40 amp relays which are controlled by a 160* sending unit in the front of the manifold. Those relays supply power to the electric water pump and electric cooling fans. Everything turns on .... above 160*, and remains on even with the key off until under 160*.
    Rear position is an ON all the time for cooling at any time.
    There may be other preferences out there, ....... but this system always works for me.

    Larry
     
  7. Golden Oldie 65

    Golden Oldie 65 Well-Known Member

    How hot does one have to get before the rings lose their tension. I threw an alternator/water pump belt earlier this year and it got hot before I noticed it. Kinda surprised me that it didn't actually boil over but my gauge goes to 240 and it was pegged past that. The bad part is it was a fresh engine. It's been running fine all summer but it does seem to smoke more than I think it should. I figured I'd have to re-ring it this winter.
     
    Gary Bohannon likes this.
  8. Bluzilla

    Bluzilla a.k.a. "THE DOCTOR"

    IMG_2967.JPG IMG_2969.JPG IMG_2961.JPG
    Not sure if this solenoid is what you are talking about. Turns out that I just got an electrical troubleshooting job on a party bus. Found this solenoid to be the problem. All the hodge-podge wiring in the photo was pre existing. Found this to be an electric golf cart solenoid. It's rated at 150 amp continuous duty. Couldn't find one locally and spent 1/2 hour at napa striking out. I ended up drilling out all the rivets and cleaning the internal contacts as well as flipping the copper conductor plate over for a new surface. Put it all back together with #6 screws and it works great!


    Larry
     
    Last edited: Oct 7, 2017
  9. 8ad-f85

    8ad-f85 Well-Known Member

    Not sure how hot for tension loss from a normal service/maintenance issue standpoint but 'too hot' causing ring butting at full throttle will both excessively wear the rings and attempt to pull the top of the piston off, widening the ring groove some.
    Then you will certainly have smoking issues at least from that if not more places.
     
  10. Jim Weise

    Jim Weise EFI/DIS 482

  11. Jim Weise

    Jim Weise EFI/DIS 482

    Bill,

    A compression and then a leak down test will pinpoint ring issues.

    JW
     
  12. Golden Oldie 65

    Golden Oldie 65 Well-Known Member

    Thanks Jim, I was thinking I should do that before I tear it down. But still, the smoking, although not real bad, is troubling.
     
  13. Bluzilla

    Bluzilla a.k.a. "THE DOCTOR"

    IMG_3132.PNG Thanks for that info Jim! I did a little more research and found that particular solenoid is rated at 85 amp continuous which should be fine for most track car applications. Cole Hersee does make a model 24213 that is rated at 200 amp continuous, .... for those who prefer a heavier duty unit. The price difference is minimal. I'm going to keep this info as I know it will come in handy at work.

    Larry
     
  14. TheSilverBuick

    TheSilverBuick In the Middle of No Where

    On my Firebird, that is electric water pump, fan, EFI, etc. I use a Ford Taurus electric fan relay, looks just like the metal single trigger one Jim posted. Got it from NAPA. I thought it's rated at 70amps continuous, but might be 85amps. I don't run the stock electronic's through it, like headlights, blower motor, radio, etc.
     

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