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CBR250rr Radiator flush problem?

Discussion in 'Bling and Appearance' started by TristanO, Dec 20, 2006.

  1. Hi I tried draining my coolant by disconecting the hose from the radiator to the motor on the left hand side of the bike. with the hose disconnected I then put the garden hose in there to try flush it out. Once all was back together I tried to refill the coolant but the resivour was already full. Then I ran the bike hoping that it would get everything moving and pump the coolant around but the resivour stayed full. Could there be an air pocket or blockage? Is it safe to ride?

  2. did you takethe cap off to let the airlock out of the radiator? You would have also had to have loosened another connection on the engine to let things bleed out.

    I would say you most likely have air trapped in the radiator now if you put in less liquid than what you drained out.
  3. I just undid the one clamp at the motor and let that drain. It may not have completely emptied it but it was th lowest point i found. When you say take the cap off to release the airlock, are you talking about the resivour cap or something else? thanks for your help
  4. There is usually a cap on top of the radiator, with a hose running to the overflow tank. I'd fill the radiator there then just top up the overflow tank.
    Do NOT undo it when hot, as it will be under extreme pressure.
  5. are you talking about the overflow reservoir holding coolant? if so that does matter. it's only the overflow. just make sure the main fluid loop has enough.
  6. dude.. to flush the coolant on the cbr, all you needed to do was take out the plug ( i know this coz i did this a few weeks ago)

    There's a drain plug on the water pump (on the right side of the bike). There's no need to take of any hoses. You probably do more harm by taking of the hoses - as you risk cracking it. But too late now.

    And you cant top up the radiator through your reservior tank. You need to take off your fuel tank, and open up your radiator cap. Top it up from the radiator cap, but make sure you fill it up completely. You can do this by leaving your motor running while you do this (but dont leave it on for too long). The coolant will 'suck' down whilst the motor is running; otherwise, it gives the apperance of being 'full'.

    for a CBR250, you want a 30% coolant mix. also, when you take off the radiator cap, make sure the seals are still okay. my one were cracked, and i had to pay $40 or so for a genuine honda cap.

    and NO - it's not safe to ride. your radiator doesnt have any coolant at the moment.

    it might also pay to get a radiator flush - coz the chances are, the previous owner of your bike hasnt flushed the coolant in a while. and if your game enough - siphon empty your resevior tank and replace it with new coolant.
  7. bravo... dont touch it if you dont know what your doing.