78 Johnson 115 starboard cylinder head getting hot

[phx5kegsman]

Hello, getting ready for summer. Ran motor on muffs. steady stream coming from telltale. Then stream started spitting (not steady). IR thermometer showed 118F port side cylinder head and and 152F on starboard cylinder head. No change in RPM's or engine sound, although, it was idling a bit high. I immediately shot off the motor. Next day I drained and removed the lower unit. I took it to my garage and put it in holding fixture. I noticed that there was water all over the top of the lower unit. At this point, I had not even loosened the impeller cover bolts yet. I don't think water came in from the mating surfaces of the exhaust housing and lower unit. I had a new impeller laying around so I put it in. I did not have a new cover so I used the old one. I did have a new gasket. Today I put the muffs back on and the same thing happened. Steady stream from telltale at first then spitting and spurting water out. The hose was on about half way. Port side temp was 120F starboard side was 162F. I have not dropped the lower unit, yet.
Any Ideas?? I really don't want to try to remove the heads. I just know, because of it's age, that broken bolts would be very likely. TIA!

 

[racerone]

The water from the telltale does not go through the block.------look for / replace diverters.---or blown head gasket.------Head must come off.

 

[Crosbyman]

if you do not wish to pull the cyl head from fear of damaged bolts have you considered some products like rid-lyme etc... maybe you can flush out some accumulated crud.
see utubes. or work slow on the bolts !

check lower cyl head hose for clogs