Reply To: 67 33HP Evinrude running very hot

[Don]

OK, so there was at least some water flow when you checked it out.   I would think that a freshly rebuilt powerhead might run a bit hotter as well, what fuel/oil mix were you using?   Had you just decelerated from WOT back to idle when you checked it, or had you been idling along?  All water pump parts were new and OEM, you might want to compare them to the old parts, just to make sure there is no manufacturing defects.  I would run a tap down through those water pump threads in the gearcase just to make sure the screws weren’t bottoming prematurely for some reason.  How about the impeller plate mating surface on the gearcase….Clean, flat, no erosion/corrosion issues?  I would use a little to the OMC type M/847 sealer between the SS impeller plate and the gearcase housing as well.  But don’t put any sealer between the impeller housing and SS impeller plate, this will ooze out into the impeller area and may hinder pump performance.  Don’t forget to check that little air bleed hole in the top of the impeller housing as well.  How about the water tube, does it appear to be bent due to previous mis-installations?   You may want to gently insert the impeller housing and grommet up and into the water tube to make sure it does not have to be pushed up too far into the exhaust housing to fit/seal properly on the grommet.  The impeller housing should be about flush with the gearcase mating surface on the exhaust housing when sufficiently connected/sealed to the water tube.

From what you said, it really doesn’t seem like the actual engine temp was high when you noticed the hot water/steam discharge.  It is possible that if you had let the engine continue to idle for a moment or two the discharge temp would have come down and the steam would have disappeared.  Do you remember trying this, or did you just look and check immediately after coming down off a high throttle setting?

The only other variable here is the exhaust housing, and other possible bleed offs to cool it.  I am not that familiar with this exhaust housing, so don’t know, just wish I had another exhaust housing to rip apart and inspect.