Chenz759 wrote:

I was looking over a boat that I am considering buying and I noticed something
strange with the outboard.
It's a 1995 Johnson 112 HP V4.
We had it running on earmuffs for a few minutes to warm it up so I could do a
compression test. I noticed that the two piston banks had a significant
difference
in temperature. After about 3 or 4 minutes, one side was still cool while the
other
side was very warm.
Anyone have any idea what could cause this? Blocked internal water passage
maybe?

The owner bought the motor new in 95 and has had it professionally winterized
every year. He did not know when or if the water pump was changed so it's
possible that it has never been replaced.
BTW, the compression checked out OK. All four cylinders measured 120 psi.

Thanks in advance,
VI

I believe each cyl bank has its own thermostat located on the aft side
of the motor at the base of the block and I suspect 1 is stuck.