how far can i drive without a radiator cap?

long story short, i gotta go to work and someone stole my radiator cap. work is 7.3 miles away, will i be fine?

Update:

it’s been missing for 5 days and i haven’t had any problems until today when i noticed i barely have enough coolant

12 Answers

Relevance
  • 1 year ago
    Favourite answer

    Having lived out in the boonies in the old days, we often would drive an old vehicle without the radiator cap just to get to a place to repair the radiator. It would help keep the coolant from blasting out under pressure. The trick is to always top off what has boiled off every time you turn off the engine until you get it fixed. This is "emergency survival operations" to get you from point A to point B where you can get it fixed. Driving it 5 days like that would be risking damage to your engine. You should top off your radiator and drive it straight to Walmart or your favorite auto parts store and get the proper pressure cap for your system.

    The cap may off shot off from not being properly put back on earlier. You might get lucky, look around the engine compartment and see if it is jammed up somewhere in there where it may have landed after shooting off.

    The cap keeps the system under pressure and keeps the coolant from boiling off, remove the cap and the coolant will boil and spew out. So when you drive it without the cap, you have to constantly refill the radiator until you can replace the cap!

  • 1 year ago

    Not likely.....

  • 1 year ago

    No, you will not be fine. Your coolant and fluid will start to boil out before you've gone a mile.

  • 1 year ago

    I'd stop at Advance Auto on the way to work and buy that $15 radiator cap! They open at 7:30am.

    Source(s): Mitsubishi Master Tech
  • What do you think of the answers? You can sign in to give your opinion on the answer.
  • 1 year ago

    Ask yourself this. How many hours will I have to work to replace my perfectly fine car. The system is pressurized to keep the boiling point higher. Yes the coolant flowing out of the cap will lessen as the level goes down. But it will overheat very fast and ruin the engine for the near future. If you drove like this for 5 days I would say the damage is already done. 

  • Anonymous
    1 year ago

    Time for a Uber ride today.  Order a cap at work from a nearby car parts store.  And it would be a good idea to get out of that neighborhood.

  • 1 year ago

    Only a moron drives a car for even one day while lacking a radiator cap.

    Enjoy the $3,000 engine replacement bill.

  • Anonymous
    1 year ago

    It's not worth the risk. Without the cap the coolant will boil leading to engine damage. Your choice of course.

  • 1 year ago

    I predict you will get 0.55 miles before the engine seizes up.

  • Anonymous
    1 year ago

    Wouldn't recommend it.

Still have questions? Get answers by asking now.