Cooling system blockage - 750SX

Discussion in 'Tech Discussion' started by Andy1399, February 15, 2009.

  1. Andy1399

    Andy1399 Member

    Hey folks,

    Had a look through the manual but it doesn't seem to explain how the cooling system actually works other than how to pull it apart and put it back together again - the vent on the left side of the nose is not bleeding water like it is suppose to, I can't say I've ever noticed it doing that (have been riding it for 4 months) one of the boys had a go on it today and noticed no water is coming out.
    We checked the lines from the intake to the engine, and from the engine to the vent, and all are clear. What else could it be? Is water suppose to flow out there or do the Kawa's have a different cooling system to the SJ's? Looking at the Schematic of the cooling system it looks as though water is suppose to flow out this vent but it doesnt explain it properly...
  2. Often you can just spray water back up that water outlet your talking about and it'l blow any blockages back out the way they came in
  3. korned

    korned Member

    Hi Andy

    Thanks for your question...

    Buy a Yami!! HOH HOH

    Bring it round we'll take a good look.
  4. bdock

    bdock New Member

    SX Cooling System Flowpath

    On a STOCK SX the water flow is as follows.

    The flow path is from the jet unit to the bottom of the exhaust manifold.
    Out of the cylinder head and on to the top of the exhaust.
    Out of the top of the exhaust expansion chamber to the water temperature sensor.
    Out of the temperature sensor and then out of the hull fitting.

    Blockages can occur at a few different locations.
    I suggest you first try disconnecting the hose from the cylinder head and flushing backwards INTO the head. This will back flush trough and out of the jet unit water intake line.
    If this is not blocked then I suggest you disconnect the hose from the exhaust expansion chamber and flush backwards through the hull fitting. This allow you to check for blockages in the water temperature sensor.

    If your ski does NOT have a FLUSHING ADAPTOR fitted then I suggest you fit one to the hose from the cylinder head to the exhaust.
    Use a TEE fitting, a TAP, and a GARDEN HOSE FITTING,

    Also - Do NOT turn the water ON until the engine is STARTED, and switch the water OFF before you STOP the engine. This prevents the possibility of water flowing into the engine through the exhaust.
  5. korned

    korned Member

    thanks, we sorted, heat sensor is full of hardened silt and shit. have bypassed and all systems flowing.

    Although you say tee into the hose from head to exhaust, there is a facotry outlet on the head that has a factory rubber bung over it, can we not just plumb flush kit onto that outlet?
  6. bdock

    bdock New Member

    That sounds like a plan. I was not sure if that was fitted to your ski.