Does the Model 9R-73B Johnson have a thermostat that shuts it down when it runs hot? Also, does the cooling water discharge spray out at all speeds or should it run out in a solid stream at higher speeds? Thanks for your help.
Mike
The thermostat regulates water flow, and that's it. If it's shutting down when hot, it's overheating and seizing due to thermal expansion. You're causing damage every time this happens.
It should have some spray of water from the exhaust relief all of the time. It increases and decreases in volume as the thermostat opens and closes and increases as RPM increases.
The 9.5 needs to be in water up to the edge of the midsection when running in a bucket.
When on the water the propeller forces water into the screened primary water intake just above it, so make sure that the screen is clear whether in a bucket or on the water.
Not the best sounding 9.5, but you can see the water sptting from the exhaust relief:
Thanks for the info. If it does shutdown due to thermal expansion, will it usually start and idle immediately afterward, but die when it is put into gear?
If it dies when you put it in gear it is either idling too slow or you are running on one cylinder; probably one cylinder. Pull the [edit] plug wires one at a time and see what happens.
Bad News!! Top cylinder has no compression and I can see tiny metal flakes when I shine a light thru the plug hole. Any estimates on what will be required and the cost if I rebuild it?
MIke
Bad News!! Top cylinder has no compression and I can see tiny metal flakes when I shine a light thru the plug hole. Any estimates on what will be required and the cost if I rebuild it?