Try something flexible that you can push up the relief hole that is clogged.
Maybe a big piece of the flap is stuck down there.

The only way to get better access is to take off the Y pipe and to do that
you need to pull the engine. Hope it doesn't come to that.

"ToneJohn" wrote in message
...
I just posted and tried the info given.. Have a Mercruise 5.7 L engine..
The exhaust flaps on one side were burnt off. I know there is a jam on the
one side because all of the water comes out on the other side, plus i can
spray water up from the out drive on the one side but not the other. Here
is what i have tried to free the debris 1) spray water down the exhaust
pipe on both sides 2) spray water up the pipe from under the out drive 3)
tried a pressure washer also. My hand only goes down to where the pipe
bends and connects from the other side....

Suggestions please...

THANKS! ! !