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8hp '90 Johnson carb flooding after multiple rebuilds

What is the ambient temperature ?----Is the thermostat installed and working ?---What is the water temperature ?-----What type and how old is the fuel ?-------Or perhaps there is something wrong with the motor and it is NOT a carburetion issue!!
 
Thanks, Racer........Also, have you done a spark test in ALL throttle positions from idle to wide open? 7/16" or better jump....snappy and blue/white color. Intermittent spark problems can drive you nuts.
 
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racerone said:
What is the ambient temperature ?----Is the thermostat installed and working ?---What is the water temperature ?-----What type and how old is the fuel ?-------Or perhaps there is something wrong with the motor and it is NOT a carburetion issue!!
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- Ambient temp in south Florida ranges from upper 60's to low 80's right now
- Thermostat - I have no idea. No one ever mentioned that in all of my questioning, so I've never checked it.
- water temp is probably close to ambient temp I would thing. Freshwater, shallow lake
- fuel is standard unleaded (ethanol free isn't easy to find near me) and not more than a couple of months old at this point

If I haven't said it enough, THANK YOU for taking the time to help!!
 
My family all now live in Florida. Tonight I'm gonna watch my pre freeze before it hits the ground. -40 actual temp with 15mph wind.....that puts wind chill at -71. The dog is using the cat's litter box, man....it's cold.
 
timguy said:
My family all now live in Florida. Tonight I'm gonna watch my pre freeze before it hits the ground. -40 actual temp with 15mph wind.....that puts wind chill at -71. The dog is using the cat's litter box, man....it's cold.
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Yeah, nope. Too cold for me. LOL!

I haven't checked spark all through the throttle range, but will. My guess is that it's not that since virtually everything in that system has been replaced.
 
Yup, my sister sent a cartoon of herself, (note Ricardo on this site).....she has herself frozen in a big block of ice today. Says it's 60 degrees in Orlando, burrrrr! Check that spark when you can, Mr. B.
 
racerone said:
Guessing does not work when trying to fix a motor.----Trouble shooting does work.
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yep, that's why I said "
I haven't checked spark all through the throttle range, but will."​

Can I take the thermostat out without fouling the seat or do I have to replace parts when I reassemble (other than the gasket for the cover)? Is there a way to test the thermostat?
 
Many seals are okay to reuse. The thermostat can be checked in hot water. Should begin opening at 140 to 145 F. Throw it away if it opens too early or too late. They are pretty precise. They fail more often than you can imagine. Correct me if I'm wrong, but they are pretty cheap to replace and you can also view into the cooling system to see how blocked it might be. The thermostat is a popular area of deposits.
 
timguy said:
Many seals are okay to reuse. The thermostat can be checked in hot water. Should begin opening at 140 to 145 F. Throw it away if it opens too early or too late. They are pretty precise. They fail more often than you can imagine. Correct me if I'm wrong, but they are pretty cheap to replace and you can also view into the cooling system to see how blocked it might be. The thermostat is a popular area of deposits.
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Forgive my ignorance here, but is this thermostat similar to the one in a car intake? Allows the engine to come up to operating temps then opens to circulate coolant (in this case, lake water) to keep temps in range? My engine pumps out water in a nice stream all the time. Does that indicate the thermostat is operational or is that irrelevant? Like does the water outlet stream happen regardless of the correct operation of the thermostat? Why would a poorly operating thermostat keep the engine from idling? I can see how it would lead to overheating (or even underheating), but poor idle?
 
The indicator stream has nothing to do with how the thermostat is working.------A liquid that is evaporating ( gasoline ) needs HEAT and on your motor that would come from a warm block.-------On a cold motor ( yes even in Florida ) the gasoline would not vaporize as well without a good thermostat.----Trouble shooting needs to be done.-----Those motors run amazingly well when they are properly tuned / set-up.
 
racerone said:
The indicator stream has nothing to do with how the thermostat is working.------A liquid that is evaporating ( gasoline ) needs HEAT and on your motor that would come from a warm block.-------On a cold motor ( yes even in Florida ) the gasoline would not vaporize as well without a good thermostat.----Trouble shooting needs to be done.-----Those motors run amazingly well when they are properly tuned / set-up.
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Excellent. Thanks for the clarification. I'll get to taking a look back there ASAP.
 
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