No tell tale stream, but not overheating

I've got a '96 yamaha 50 hp.
I can't get a tell tale stream.

I've replaced the impellor.
I've replaced the thermostat.
I've run the engine for up to 10 minutes (idle and medium
throttle) and the engine temp doesn't get over 135.
It was in saltwalter, but for the last year has been running
exclusively in freshwater.
I don't get an overheating alarm.
I've tried fishing around in the outlet - nothing.

I've seen something about a poppet valve?
A possibility? Where is it?

thanks.

[neverenoughx2]

stick a long thin wire in the tell tale. sometimes a little dirt clogs it.

I did insert a wire

I was able to insert a wire about a 12"
up the tell tale.
Could I have hit an obstruction or is that as far
a wire can go?

Tell Tale Stream

I am not sure how far you can get up the tell tale line, but I prefer to use a piece of weed-whacker (string trimmer) cord. If you use a piece somewhere in the range of .080 diameter, it us stiff enough to do the job and a lot more flexible than wire.