No water out of exhaust.

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wengr

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Hello. 1996 Merc 5.0 Alpha one Gen 2. Trying to run on muffs. But no water output from exhaust. Pulled lower to inspect impeller. Looks good but will replace with Quicksilver anyway. However when I removed the lower unit a rectangular piece of plastic fell out of the drive. It's a bit larger than a credit card. No idea what it is. Best guess is it half of a flapper assembly, but I cannot find any sign of a flapper that looks anything like this. Any advice as to what it could be, and why I have no water out of exhaust is appreciated. Thermostat? Flappers?
 
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Kola16

Kola16

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Post a picture of the part. Did you look at your drive's parts diagram? There are not very many plastic parts.
 
Scott Danforth

Scott Danforth

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at low speeds and the low water flow of a hose while on the muffs, most of the water will come out the idle relief ports.

most likely the bit of plastic is what is left of your flappers
 
1985 Century Mustang

1985 Century Mustang

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wengr said:
Hello. 1996 Merc 5.0 Alpha one Gen 2. Trying to run on muffs. But no water output from exhaust. Pulled lower to inspect impeller. Looks good but will replace with Quicksilver anyway. However when I removed the lower unit a rectangular piece of plastic fell out of the drive. It's a bit larger than a credit card. No idea what it is. Best guess is it half of a flapper assembly, but I cannot find any sign of a flapper that looks anything like this. Any advice as to what it could be, and why I have no water out of exhaust is appreciated. Thermostat? Flappers?
Click to expand...

You can try removing the thermostat first. See what happens.
 
Scott Danforth

Scott Danforth

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I wouldnt remove the thermostat. it is used as a mixing valve on I/O's without it, the block gets too much water flow and the exhaust doesnt get enough.
 
Kola16

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That is it, well done! Did you overheat the engine, or did you shut it down soon after startup when you realized there was no water? Only asking because if the exhaust had no water cooling and got too hot, your internal exhaust flappers may have been melted. You can take off the lower boot between the Y-pipe and the 90 degree elbow to inspect the flappers if you suspect they got overheated.
 
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wengr

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Kola16 said:
That is it, well done! Did you overheat the engine, or did you shut it down soon after startup when you realized there was no water? Only asking because if the exhaust had no water cooling and got too hot, your internal exhaust flappers may have been melted. You can take off the lower boot between the Y-pipe and the 90 degree elbow to inspect the flappers if you suspect they got overheated.
Click to expand...
I am at my home de winterizing and prepping for sale. I have not run it for longer than 25-30 seconds because I see no water being drawn in or expelled anywhere. I will certainly kook at the flappers for good measure. So what is a filler wall, and if I orientate it correctly I should be good to go?
 
Scott Danforth

Scott Danforth

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the filler wall is in the upper section, just above the split for the lower. use a bit of grease to hold it in place while you slide in the lower.
 
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