HELP yz426 coolant leak

Alrite I have used to have a 00' yz426 motor in a 400ex frame and that thing after riding a while would always start dripping coolant out of the weep hole underneath the water pump cover, so I replaced the seals and everything and it continued to do it. Currently now I have a 01' yz426 motor in the 400ex frame and was out riding it tonite and I stopped and looked down and not just a little bit of coolant was leaking out..it was pouring. I could also hear like it was boiling. The radiator was very very hot so I am sure it was overheated, but I just wanted to know if that coolant shooting out of there so fast was just a result of the overheating? I am pretty sure the seals are good in this one..(it wouldnt hurt to check tho). Just let me know if this is normal...it does not do it when the engine is just running warm only when hot hot.

YOU MIGHT HAVE A BAD HEAD GASKET.YOU COULD ALSO HAVE A BAD WATER PUMP.ALSO DON'T SIT IN ONE SPOT WITH YOUR MOTOR RUNNING AFTER THE BIKE IS ALL READY WARMED UP THIS WILL CAUSE THE BIKE TO LEAK FULID. :thumbsup:

Rider for life is right, you either got a blown head gasket or a possible water pump problem. Nah its not normal to have coolant just boiling/pouring/dripping out of the motor. You might see a lil coming out of the drain but it will only drip if your sitting for a longer period of time.

you also need to make sure the seal is placed in the proper direction. if the seal is reversed it can also cause trouble. sorry, i was talking about the waterpump seal.

I have a yz 400 and if I ride hard then stop and idle for a bit it will boil over. Just don't idle for long, these bikes get hot and they love to move! I've also heard of people getting different radiator caps that can take more pressure. :thumbsup:

Welcome to TT Bodia

YOU MIGHT HAVE A BAD HEAD GASKET.YOU COULD ALSO HAVE A BAD WATER PUMP.ALSO DON'T SIT IN ONE SPOT WITH YOUR MOTOR RUNNING AFTER THE BIKE IS ALL READY WARMED UP THIS WILL CAUSE THE BIKE TO LEAK FULID. :thumbsup:

BTW when you use all CAPS it's like you're yelling at us. :confused:

thanks :thumbsup:

if its leaking out the weep hole again then the water pump and seals AND shaft need to be replaced. if it is continousally coming out your radiator cap then you need new head gaskets

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