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Johnson 9.9 Water Cooling System Repair NEED HELP

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LeeRM

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So I've been trying to solve a water flow and cooling issue on my Johnson 9.9. At first, the water stream from the tell tale or pee hole was very weak and sometimes nonexistent. Here is what I have done so far along with the results:
  1. Replaced the water pump impeller and cleaned salt deposits on the lower end. Seemed to pick up water from the intake, but it only discharged water from the lower leg and not the tell-tale.
  2. Poked a paper clip through the tell tale to discover that nothing was obstructing it there.
  3. Proceeded to inspect the thermostat; decent amount of corrosion, can't necessarily conclude that it is stuck shut.
  4. Ran motor without thermostat installed and the enclosure open to see if water pukes out; water puked out sufficiently
  5. Closed up the thermostat port door with the thermostat removed to see if water would flow through tell tale anyways while running; No water through the tell tale, and I've noticed that some water is spraying through the exhaust instead. In conclusion, the thermostat may not be the main issue, since water does not exit through the tell tale even without it installed.
  6. I removed the hose that connects the tell tale to the power head and as I predicted, it was completely cleared.
I fear that the issue lies within the powerhead, since I do not feel entirely comfortable disassembling the engine any further than I already have. Although, I can't be certain that is where the blockage is. Please let me know what course of action I should take next. Also feel free to leave any questions to clear up any confusion. I could leave pictures as well.
 
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***UPDATE***
After reassembling the entire engine and running it, water flow has returned to the telltale, but it is quite weak and water is finding its way through the exhaust. Not sure if this is terrible news or not, since I was able to idle it for around 5 minutes without any other signs of problems. I'm still curious if this is an issue worth investigating.
 
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FIRST OFF,dont run engine without a thermostat,not enough back pressure on cooling system to run properly. THermostat can be checked while immersed in a pot of water on stove. Was impeller housing sealed properly when it was installed? Is engine really overheating? Can hand be placed on cylinder head for 6 seconds? Is water stream out of telltale to hot to touch? Has compression been checked?
 
johnnygjr said:
FIRST OFF,dont run engine without a thermostat,not enough back pressure on cooling system to run properly. THermostat can be checked while immersed in a pot of water on stove. Was impeller housing sealed properly when it was installed? Is engine really overheating? Can hand be placed on cylinder head for 6 seconds? Is water stream out of telltale to hot to touch? Has compression been checked?
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Don't worry, I only ran the engine without a thermostat for a quick check that the water impeller/housing was indeed working and sealed. Thermostat is definitely working. The cylinder hear is not overheating whatsoever nor is the water from the telltale even after multiple minutes, despite some usual warmth. Not sure how to check the compression, but the only issue I see now is that water from the telltale is somewhat weak and water some water is exiting through the exhaust port on the midsection. Other than that, engine seems to run fine.
 
Borrow a compression tester from a auto parts store, It screws into spark plug threads,fully charge battery,crank engine over3-4 cycles with all plugs removed,take readings
 
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