3.0L Mercruiser rough idling/accel.
 

Hi all- I have a '99 18' SeaRay 3.0L with about 75 hours on it. Always
prof. winterized, oil changed etc. Last time I was out I noticed a very
rough idle (around 1000 rpm) seemed like it might stall but never did. It
had that rise/fall sound to it. Also, it seemed to bog down during
acceleration and definitely wasn't moving the way it should with the tach
indicating around 3000 rpm. Suddenly accelleration seemed to kick in with
the tach reading 4000 rpm and the boat surging forward. I'm setting up an
appt. with the Mercruiser mechanic but was wondering if anyone had ideas as
to what might be going on here? (I'm still operating with some of last
years fuel with the Sta-Bil added to it, as I haven't had a chance to use up
the old fuel and completely refill the tank.)
Thanks. Andy

3.0L Mercruiser rough idling/accel.
 

My boat does the same thing. A tune-up and timing adjustment really helped,
but it surges and idles rough after running all day. The best diagnosis so
far is a carburator rebuild with a new needle valve and float.

Unfortunately, when I took mine out I also discovered a new leak coming
through the outdrive. :/

-gattman
87 Searay 18'


"Andrew Heller" wrote in message
...
Hi all- I have a '99 18' SeaRay 3.0L with about 75 hours on it. Always
prof. winterized, oil changed etc. Last time I was out I noticed a very
rough idle (around 1000 rpm) seemed like it might stall but never did. It
had that rise/fall sound to it. Also, it seemed to bog down during
acceleration and definitely wasn't moving the way it should with the tach
indicating around 3000 rpm. Suddenly accelleration seemed to kick in with
the tach reading 4000 rpm and the boat surging forward. I'm setting up an
appt. with the Mercruiser mechanic but was wondering if anyone had ideas
as
to what might be going on here? (I'm still operating with some of last
years fuel with the Sta-Bil added to it, as I haven't had a chance to use
up
the old fuel and completely refill the tank.)
Thanks. Andy