Honda BF10, BF8 and BF75 Water circulation issues.

[w2much]

Have seen quite a few problems with cooling these engines. Seems like the cooling system tends to clog at the thermostat. Not always an easy job to remove the manifold. Wondering if this is a common occurance with these engines. Should I just leave the thermostats out? I live in San Diego so cold running is not much of an issue.

 

[Sea Rider]

Were all those mentioined OB models properly flushed with fresh water after their outings, or are OB's that live moored and never flushed after use. If thermo is removed, OB will take longer time to reach its correct operational temp, same with restarts after cooling down. Try Salt Away Products, should work as stated..

Happy Boating

 

[timmy3131]

I'm having an issue now with my BF75. I think it's a 1985 it doesn't really seem to be overheating. But no water is coming out the telltale. I pulled the water pump apart and it looks great! No issues or cracks can someone give me a direction where to look. It's only been in fresh water. It's a long shaft. I checked the telltale tube and it's clear. I will be using it in the fall for 10-15 minute trips

 

[Sea Rider]

If lower leg is still down, connect a hose up water tube and flush with high water pressure. Can also remove thermo , connect a water hose in thermo orifice and flush for some minutes with high water pressure, seems there's a clog in the water passage before telltale outing.

Happy Boating

 

[w2much]

Sea rider you are right. Lots of salt and crud. Perhaps I should have been more patient with a hose and salt away. Instead I went for the thermostat. The manifold bolts were a bear and had to soak for several days. Finally decided to just remove the whole head to make removing the manifold easier and to avoid my worst nightmare broken bolts. Soaking , heat and patience worked well as the broken bolt scenario was avoided. So now its up and running and cooling properly although I did leave out the thermostat.
I have a whirring sound now mentioned in another post.
Thanks for your reply

 

[Sea Rider]

It's amazing how much salt formations an OB can collect internally on all cooling water passages. Much worse if OB is not correctly flushed with fresh water soon after its use.

Happy Boating