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4.3 Mercruiser excessive water out exhaust through prop

K

Kyle Thomas

New member
Hi All, 97 4.3mercruisre has excessive water coming out prop. Port side exhaust cool and water comes out exhaust correctly. Starboard side hot and most of this water seems to be coming out the prop. No water in the oil. Flappers all removed. Any advise on a approach to take would be appreciated. Thanks Kyle
 
Docksidemarineservices said:
Start by dropping the lower unit and inspecting the water feed from the pump.
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Thanks Chris, the stern drive is new, SEI Alpha, I removed the starboard side exhaust at the rubber fittings and the water is flowing well' It comes out the top section of the riser and then joins the exhaust gas. There is a lot of corrosion and some small pieces were removed with a magnetic flexi stick. I take it that the block is therefore being cooled correctly, just a restriction at the water exit point in the gimbal exit. as there is some flow. Once the engine is warm, I can still put my hand in the hot water. I assume the exhaust gas and water meet down the bottom and the water is being 'forced' out the prop due to the restriction. I take its OK to run the motor like this as its still being fully cooled? And then do a rebuild in the winter, I'm in Sydney.
 
Kyle Thomas said:
Thanks Chris, the stern drive is new, SEI Alpha, I removed the starboard side exhaust at the rubber fittings and the water is flowing well' It comes out the top section of the riser and then joins the exhaust gas. There is a lot of corrosion and some small pieces were removed with a magnetic flexi stick. I take it that the block is therefore being cooled correctly, just a restriction at the water exit point in the gimbal exit. as there is some flow. Once the engine is warm, I can still put my hand in the hot water. I assume the exhaust gas and water meet down the bottom and the water is being 'forced' out the prop due to the restriction. I take its OK to run the motor like this as its still being fully cooled? And then do a rebuild in the winter, I'm in Sydney.
Click to expand...

Ayuh,.... The water, 'n exhaust meet right at the end of the risers, not at the bottom of the y-pipe,....

If you've got a problem with flow through the y-pipe, the most likely answer is an old burnt up shutter is layin' in there,....
 
bondo said:
Ayuh,.... The water, 'n exhaust meet right at the end of the risers, not at the bottom of the y-pipe,....

If you've got a problem with flow through the y-pipe, the most likely answer is an old burnt up shutter is layin' in there,....
Click to expand...
Thanks mate, I previously removed about 4 of these burned shutters, not to say there are not more down there, do you think its Ok to run like that with the water coming out the prop?
 
Hi Chris, the overall flow out the back is the same as when the one side was flowing normally, its now just mostly out the prop, which has always had slight flow; so I believe the new stern drive is pumping at max flow through the engine and out the exhausts and prop.
 
If you have a pressure water leak in the drive after the pump, it will flow right out the prop hub. If you don't want to at least check it. that's ok.
 
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Remove the water inlet hose inside the engine bay where the hose from the T'stat snakes thru the PS cooler then to the hull. That inlet pass thru can close up from corrosion. That may be what Chris is saying any blockage will force most out the hub.
 
guyjg said:
Remove the water inlet hose inside the engine bay where the hose from the T'stat snakes thru the PS cooler then to the hull. That inlet pass thru can close up from corrosion. That may be what Chris is saying any blockage will force most out the hub.
Click to expand...

Thanks,


Actually not concerned with a blockage but rather a water leak after the pump inside the drive. Possible forgotten oring, Cracked Coupling, cracked water tube, missing water tube seal, missing water tube....Ect

This is an SEI Drive. Did it come assembled?
 
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