Coolant Overflow ?

I replaced my cylinder head  awhile ago on a sm with a e head with e cams aswell, now i have coolant overflowing constantly from the expansion, so bad even, my left leg was covered in the green.

I am trying to work out why this is, i am thinking maybe i should take the thermostat off i really don't know.

Also the head itself gets very hot, overly hot i would say, aswell as the oil filter case the stator caseing side even the clutch case was quite hot.

I think tho the oil filter stator and clutch caseings have stopped getting so hot but i really haven't been able to run the bike for a long time to test it out fully.


Any ideas ?



Are you sure you properly bled the coolant system?

You can start with the thermostat. A thermostat that doesn't open will cause your problems and it will not light up your overheat indicator or even start up the fan.


For as much work as youv'e done on your head you should fix this as soon as possible before it gets really expensive.


If you remove the thermostat it should  be replaced by an oring.  If the thermostat removal doesn't fix the problem it's time to pull the head. What ever the origional problem was the head more than likely has been overheated enough to warp and allow exhaust to enter the coolant.


Check the head surface for flatness. Closely examine the headgasket for falure spots. To be extra sure it might be wise to check the flatness of the cylinder itself.



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