I have a 1985 Mercury 9.9 outboard . Can i reverse flush my cooling lines by feeding hose pressure water in through the pee hole? If so will the water exit from the intake plate just above the prop?
outboard flush
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Need to run the engine
No - the water pump will block the water flow. You need to run the engine in fresh water to get it up to the block. Try using a 5 gallon bucket with a lid. Cut out an openin in the lid to allow the lower unit and prop to fit into the bucket. Have the motor supported so you can run it on dry land and fill the bucket with fresh water. I do this with my 3.5 outboard and it works well. You may need a larger bucket with a 9.9.
No - the water pump will block the water flow. You need to run the engine in fresh water to get it up to the block. Try using a 5 gallon bucket with a lid. Cut out an openin in the lid to allow the lower unit and prop to fit into the bucket. Have the motor supported so you can run it on dry land and fill the bucket with fresh water. I do this with my 3.5 outboard and it works well. You may need a larger bucket with a 9.9.
yes, run the engine
...I use the ear muff type flusher over the water intake. Of course, the prop cannot be engaged. You must run it long enough to get the motor up to temp and open the thermostat to get the fresh water into the head area. Running it in a bucket will work but the water will heat up quickly so keep the fresh water hose flowing to replentish. There should be a flush plug, just to the right of the gear oil plug... I have one on my Tohatsu 9.9, but the motor must be off to use it so the fresh water still won't get up to the motor head.
...I use the ear muff type flusher over the water intake. Of course, the prop cannot be engaged. You must run it long enough to get the motor up to temp and open the thermostat to get the fresh water into the head area. Running it in a bucket will work but the water will heat up quickly so keep the fresh water hose flowing to replentish. There should be a flush plug, just to the right of the gear oil plug... I have one on my Tohatsu 9.9, but the motor must be off to use it so the fresh water still won't get up to the motor head.
I use a trash bag...
I think it is 42 gallon 3 mil contractor trash bag I got at Home Depot or Lowes. I tilt the engine out of the water and let it drain. Place the engine in the bag and lower the unit back into the water. I then put the hose in the bag and turn on the fresh water. After a few minuets, I start the engine and fresh water comes flowing from the outtake hole. Works like a charm. Works great if you need to keep the motor in the water, also. Put it in a bag and lower it back in to the water. Stays dry. But on my Yamaha 9.9, I used the reverse flow method to clear a clog. It worked and water came out of the intake port. However, I need to replace the impeller but not because of the reverse flow. I haven't used the motor in a while and water is not flowing out of the outtake. [added] Oh... and get some Salt Away for when you flush the cooling system.
I think it is 42 gallon 3 mil contractor trash bag I got at Home Depot or Lowes. I tilt the engine out of the water and let it drain. Place the engine in the bag and lower the unit back into the water. I then put the hose in the bag and turn on the fresh water. After a few minuets, I start the engine and fresh water comes flowing from the outtake hole. Works like a charm. Works great if you need to keep the motor in the water, also. Put it in a bag and lower it back in to the water. Stays dry. But on my Yamaha 9.9, I used the reverse flow method to clear a clog. It worked and water came out of the intake port. However, I need to replace the impeller but not because of the reverse flow. I haven't used the motor in a while and water is not flowing out of the outtake. [added] Oh... and get some Salt Away for when you flush the cooling system.
Use a Hose Adapter
On my '84 merc 7.5 I use a garden hose adapter that will flush the motor. I picked it up at a Mercury dealer.
On my '84 merc 7.5 I use a garden hose adapter that will flush the motor. I picked it up at a Mercury dealer.
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