ALso make sure that you have reassembled the thermostat housing
properly and that the plastic poppers are working freely.- Hide quoted text -

- Show quoted text -

I agree with the last work done being the probable culprit. As I think
about it, the plastic poppers may be a little looser than they should
be (my fault, but easy to fix), if so, do you think the pressure could
force only one side open sending water to the port and not starboard
in this case? I'm going to pull the riser and check the manifold for
anything visible, they need to be replaced as a preventative measure
anyway. My risers are stainless. The boat was a freshwater boat most
of its life, this is year 3 in the salt. I have to admit a few of the
manifold bolts were pretty frozen and rusted round so I put the
project off hoping to get another season as they may need to be cut
off by a pro. Bad idea, I know. I often flush with fresh water and
at least run the engine 3-4 times a week to keep water flowing and
crap from building up the best I can. I'm going to check my flapper
also, I replaced the port one last season because it was making noise,
I should have done starboard at the same time but I was in a if aint
broke don't fix it mood. Thanks