4efte overheating under boost

Discussion in 'ENGINE' started by Fahim, Sep 4, 2017.

  1. Rev

    Rev Registered User +

    Good question.
    Initially most connections to the engine except the large hose behind the waterpump with main failure behind the thermo hosing and leaking from radiator cap,tap and from overflow bottle cap as well.

    Leaking now from overflow bottle with new leak in large hose behind the waterpump thought this was only an issue at higher revs.

    Last week was in the country with some hills at say max 5000rpm on freeway plus city driving a few days now I notice a leak back of thermo housing from the small pipe going to the air intake.

    So air currently getting in but mostly bleeding through the overflow bottle cap.
    None of the hoses that have been replaced are leaking.
  2. Fahim

    Fahim Fresh Recruit

    Brother your issue sounds like your engine is pressuring your water.
  3. Rev

    Rev Registered User +

    Thanks that may well be the case but there are other major repairs needed as well. In the meantime I am hoping eliminating air from the system with new hoses will keep things going on a daily basis.
    Last edited: Sep 13, 2017
  4. Fahim

    Fahim Fresh Recruit

    Installed thermostat,same problem remain.
    Car overheats under boost or high rpm only
  5. Rev

    Rev Registered User +

    Sorry to hear you have that issue still.

    Many factors involved of course, my worst over heating was a head gasket was blocking the head openings. I would look at the turbo piping is it getting water/oil flows ok. Also would check obvious things eg maybe the 1000deg exhaust manifold is too close to something and adding too much heat to the system.
    I haven't done the figures someone might know if an excessively blocked cat could prevent heat escaping the combustion chamber fast enough. Good luck.
  6. Fahim

    Fahim Fresh Recruit

    I dnt have a cat,i have a free flow straight ss piping exhaust.
    Btw can a a faulty witing cause a engine to overheat?
  7. SKINY

    SKINY Registered User +

    Does your radiatior fan work ??
  8. Fahim

    Fahim Fresh Recruit

    Yes radiator fan works perfectly,
    Bt from my garage they said as its a project car,my wiring wasnt done properly after the engine conversion,and they said to do the wiring newly.
  9. Rev

    Rev Registered User +

    Verifying the temp sensor/gauge are ok is worth checking as it effects a lot. Sensor functions are in this link:
    Last edited: Sep 26, 2017
  10. dac69er

    dac69er Super Moderator

    that would have no effect on it overheating as long as the fan is coming on.
    as the OP said, the car does not overheat under normal driving or sitting idling.

    it is a crack/warp in the head or block
  11. Rev

    Rev Registered User +

    I agree overheating symptoms occurring very quickly ( excluding knock ) do point towards combustion leaking rather than timing wasted heat of combustion.

    However could the carbon buildup shown at the exhaust port piston photo indicate some excessive retard from electrical/timing as well ?
  12. Fahim

    Fahim Fresh Recruit

    Today i boosted my car alot,and when i came to a stop
    My gauge was reading 94c.
    Bt when i came to a stop i saw lots of white smoke coming through the tail pipe,but when i start to drive the car again,there were no white smoke.
  13. Rev

    Rev Registered User +

    What you are indicating is the oil temps went above 100C so moisture was vaporized out of the engine which is what its designed to do. I have read in racing there is a rule of thumb water temp plus approx 16C so your oil say 110C which will thin oil a bit. (as oil thickness is usually rated at 100C)

    It seems consistent with one symptom of running without a thermostat ( or pcv ) that water vapor doesnt get hot enough and can get caught in the engine which may increase engine wear.

    I am curious if temps have now dropped a little with the water vapor gone? but suspect oil quality may effect temps more than a small amount of water in the oil.
    Last edited: Oct 4, 2017
  14. Fahim

    Fahim Fresh Recruit

    No i have thermostat and pcv valve in my car.
  15. Rev

    Rev Registered User +

    You mentioned the issue was there before your engine changes.
    Hot ambient temps. are the constant here so its worth mentioning these can result in TMIC heat soak and engine pulling timing as well. Other posts show people reaching higher temperatures than your 94C so if everything is in good shape like head,oil type,oil levels, turbo blades,radiator,cap etc next thing to consider would be a FMIC to suit your conditions.
    Last edited: Oct 7, 2017
  16. Jay

    Jay Admin

    Any further updates on this?

    You could perform a sniffer test on the cooling system to confirm the presence of exhaust gases in the coolant. That would point to headgasket/cylinder head/block again though.
  17. Skalabala

    Skalabala Registered User +

    Its not smoke its steam most probably. Replace the head gasket, use copper gasket spray on it. Clean head bolt threads in block 100%
    And the clean head and block surface with alcohol. Also make sure your timing is set right.

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