Amount of Exhaust Water out the back

Sep 28, 2020
4
ODay 28 Lake Allatoona
Hello all!

This summer I replace the Impeller on my Sherwood twice after it failed. I recently upgraded to an Oberdorfer water pump. I have replaced the water muffler, exhaust system up to water muffler and everything else I could think of. I continue to only have a minimal amount of water exhaust and wanted to know if this was normal, also seeing some steam in the exhaust. All hoses are tight, thermostat is new. Any ideas, anyone else have had this issue? It is dripping and then it will dump a half a cup of water every 15 seconds or so. It is a Universal Diesel 5411. Thanks for your help.
 

dmax

.
Jul 29, 2018
969
O'Day 35 Buzzards Bay
That's not enough flow, every couple of seconds there should be a burst of water with some dribbling in between. Steam is not what you want to see, just water. You likely have pieces of the failed impellers lodged in a hose or the heat exchanger restricting the raw water flow. Start at the Oberdorfer and take everything apart and make sure its clear.
 
Jan 7, 2011
4,723
Oday 322 East Chicago, IN
If it was me, I would start with the water intake and check along the way...

1) Is the thru hull clean and open?
2) is the strainer clean ?
3) are you getting good flow out of the hose right before it goes into the pump?
4) can you check to see what sort of pressure/flow you have after the pump?
5) if a fresh water cooled boat, have you inspected the HX?
6) have you checked the mixing elbow to see if the water injection port is plugged ?
7) are you getting good exhaust gas flow out of the exhaust? any other indication of an obstruction in the muffler?

Along the way, I would be pulling the hose off (thru-hull closed of course), putting the end in a bucket, and opening the valve to see how good the flow is...

Eventually, you will find the cause.

Greg
 
Sep 28, 2020
4
ODay 28 Lake Allatoona
If it was me, I would start with the water intake and check along the way...

1) Is the thru hull clean and open?
2) is the strainer clean ?
3) are you getting good flow out of the hose right before it goes into the pump?
4) can you check to see what sort of pressure/flow you have after the pump?
5) if a fresh water cooled boat, have you inspected the HX?
6) have you checked the mixing elbow to see if the water injection port is plugged ?
7) are you getting good exhaust gas flow out of the exhaust? any other indication of an obstruction in the muffler?

Along the way, I would be pulling the hose off (thru-hull closed of course), putting the end in a bucket, and opening the valve to see how good the flow is...

Eventually, you will find the cause.

Greg
1) Is the thru hull clean and open? Yes
2) is the strainer clean ? Yes
3) are you getting good flow out of the hose right before it goes into the pump? Yes
4) can you check to see what sort of pressure/flow you have after the pump? I pulled the line after the thermostat and the water is flowing strong, looks like the water is getting through the motor correctly. I have checked the hoses for obstruction but I can't find any?
5) if a fresh water cooled boat, have you inspected the HX? Not sure what HX is but will Google it.
6) have you checked the mixing elbow to see if the water injection port is plugged ? I will!
7) are you getting good exhaust gas flow out of the exhaust? any other indication of an obstruction in the muffler? I checked the muffler and it's clear.
 
May 17, 2004
5,026
Beneteau Oceanis 37 Havre de Grace
Is the engine raw water or fresh water cooled? You say water is flowing strong after the thermostat, but the thermostat is only in the raw water circuit with a raw water cooled engine, so I guess that’s what you’ve got?

What happened to the previous impellers? My guess is one or more vanes are stuck in the path somewhere. I’d suggest in the heat exchanger but I don’t think a raw water cooled engine would have one.
 
  • Like
Likes: ggrizzard
May 29, 2018
457
Canel 25 foot Shiogama, japan
I know it is winter and the ambient is low, but what temp was the engine running at before the upgrades and what temp does it run at now?

gary
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
When you removed the failed impellers, did you count the vanes? The heat exchanger has a lot of small tubes that the cooling water flows through, it is a common final resting place for errant impeller vanes.

The mixing elbow is the next most likely suspect. Take it off, clean it, and inspect for rust. These parts often have a high failure rate.
 

Ward H

.
Nov 7, 2011
3,645
Catalina 30 Mk II Barnegat, NJ
I had to DuckDuckGo to find out but it looks like the 5411 is sea water cooled so no HX.
I would be concerned that impeller vanes are lodged in the water passages of the block.
Going by your previous list of checks the next is to check the water coming out of the hose at the water injection port.
 
  • Like
Likes: ggrizzard
Jan 5, 2017
2,263
Beneteau First 38 Lyall Harbour Saturna Island
I had to DuckDuckGo to find out but it looks like the 5411 is sea water cooled so no HX.
I would be concerned that impeller vanes are lodged in the water passages of the block.
Going by your previous list of checks the next is to check the water coming out of the hose at the water injection port.
Ward, I think you could get them either way. The 5411 in my E-28+ had a HX.
 
May 27, 2004
1,964
Hunter 30_74-83 Ponce Inlet FL
I don't agree Jim, but then I've got an older boat!
On a saltwater cooled engine, I'd grind the rust, check the part for deterioration and integrity, then, if the part is still usable, treat the rust areas with your favorite rust passivate/preventative.
 
Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
Do not clean off the Rust. Rust is the protective Oxide.
Clean off the carbon.;)
Jim...
Injector exhaust elbows rust through. Then they leak and spew hot dirty water and exhaust gases through out the boat which is closed up because of the thunderstorm that takes away all the wind for hours while sitting in a shipping lane 14 miles offshore. Just sayin'
 
Oct 24, 2010
2,405
Hunter 30 Everett, WA
When we purchased our current boat there was a problem with one of the hoses. It had a flap of rubber that would drop down like a check valve if you push the throttle up far enough. Then the engine would overheat. If you pulled the throttle back it would not cool back down. If you shut it off and then ran it at a low power setting it didn't overheat. But it was actually a hose with a flap of rubber inside blocking the flow. That was tough to find. I found it by accident.

I'd suggest disconnecting the hose where it goes to the exhaust manifold and see if you have good flow there. With the engine running, It should be almost like a garden hose at that point. if the flow is weak there, back up to where the hose it hooks to the input of the heat exchanger. Same drill there. Eventually you'll find where the problem is.
 
Last edited:
  • Helpful
Likes: Ward H
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Injector exhaust elbows rust through.
Possible for sure, just don't clean off the rust inside to hurry up the corrosion process.
Jim...

PS: My Volvo Penta quenching design does not have that issue. The quench hardly contacts the metal as it cools the exhaust that contains SO2, CO2 and CO which make mild acids.
 
Feb 8, 2014
1,300
Columbia 36 Muskegon
The 5411 has a weird cooling system. Raw water cooled and the way it's plumbed almost no water is expelled until the thermostat opens. As the t-stat starts to open a little water is sent out the exhaust and is replaced by an equal amount pulled in through the intake. When cold only the tiny amount going through the little bypass hole gets sent out the exhaust. You don't get the "normal" amount of flow that other engines make until it's fully warmed up. This is perfectly normal and by design. There's nothing wrong with your engine or pump, although you did good swapping to the Oberdorfer. The Sherwood is a POS, it would have started leaking sooner rather than later.
 
  • Helpful
Likes: Ward H
Feb 8, 2014
1,300
Columbia 36 Muskegon
I had to DuckDuckGo to find out but it looks like the 5411 is sea water cooled so no HX.
I would be concerned that impeller vanes are lodged in the water passages of the block.
Going by your previous list of checks the next is to check the water coming out of the hose at the water injection port.
The HX was an after market add on. Mine had one but it developed a crack and leaked. I took it off and went back to raw water cooling. Fresh water so no foul.