poppet valve ??????

[ttles714]

A did a search but patience in NOT one of my virtues !!!!! will someone be so kind as to explain the function of the poppet valve on an SX250 (ox66) ? What would the symptoms be for a non functioning valve ?

thanks much

[99yam40]

the valve opens under high pressure dumping some of the water not needed at high RPM.
if it sticks open then there may not be enough water to fill the block at low RPM

[ttles714]

much appreciated ...... so could this be the culprit in the following scenario ? Runs good at cruise and above ... when Idling back down to 1K rpm, horn goes off , still pissing water though .... shut off engine for a minute or two and all back to normal .....

[99yam40]

simple enough to inspect, clean, or replace to see it helps.

when you say back to normal, does that mean the motor will run at low speed again without overheating until you run high RPMs and it repeats the alarm at low speed?

[ttles714]

yes, thats what happens

[99yam40]

I guess it could be that when run at high RPMs the PRV opens and sticks open for a while,
but once it does close it is good until the motor opens it back up again.
all I can say is look and try