Didn't get much feedback on boat diesel, need suggestions

[ageless]

Awoke the other AM to sheen coming from port exhaust, while shut down, mind you. I went to ER and shut off fuel valves, sheen stopped. Flipped on ER fans for 10 minutes or so, turned on fuel valve and cranked her up. Typical gray smoke for 30 sec's and cleaned right up, no misses, no other wierd smoke, NO SHEEN at idle. Let it run for 15 minutes with no changes on gauges, shut it down. A minute later the sheen started again until I shut the valve off.

My first thought was fuel cooler as there was no smoke or unusual engine behavior. Any other suggestions outside of that or a bad injector?

 

[dsharp]

The only way to know for sure is to pressure test the cooler or rob the cooler off the other engine and run it for a minute

 

[ageless]

The only way to know for sure is to pressure test the cooler or rob the cooler off the other engine and run it for a minute

radiator shop can pressure test, correct?

 

[kelpy]

With the engine off, a leaky injector or fuel cooler would have to run uphill to come out the exhaust.

 

[ageless]

With the engine off, a leaky injector or fuel cooler would have to run uphill to come out the exhaust.

Ah, very good point. Now I wonder if it's from the generator exhaust

 

[Pete]

For a first step you might try pulling the raw water hose off the exhaust spray head, lower this into a bucket and let it drain. See if any fuel settles on the surface. This should give you an indication on the source, either the cooling system, or the dry gas exhaust system.

Pete

 

[ageless]

For a first step you might try pulling the raw water hose off the exhaust spray head, lower this into a bucket and let it drain. See if any fuel settles on the surface. This should give you an indication on the source, either the cooling system, or the dry gas exhaust system.

Pete

would you clarify what the exhaust spray head is, I likely know by alternative name

 

[Pete]

In the exhaust system, there is a "riser" off the back of the engine that runs uphill and then takes about a 90 degree turn going down hill headed to the mufflers. It is wrapped in insulation, and clearly the largest pipe in the engine room.

Just following the peak in this pipe there is a water hose that attaches, that injects the raw water into the exhaust system. In side the pipe this water is injected by what is called a shower head or spray head that converts the solid water flow into a circular spray pattern to cool the exhaust piping.

The hose I referenced is the one that attaches to the exhaust just after its peak, and likely in the range of 2 to 3 inches depending on the engine.

Pete

 

[ageless]

In the exhaust system, there is a "riser" off the back of the engine that runs uphill and then takes about a 90 degree turn going down hill headed to the mufflers. It is wrapped in insulation, and clearly the largest pipe in the engine room.

Just following the peak in this pipe there is a water hose that attaches, that injects the raw water into the exhaust system. In side the pipe this water is injected by what is called a shower head or spray head that converts the solid water flow into a circular spray pattern to cool the exhaust piping.

The hose I referenced is the one that attaches to the exhaust just after its peak, and likely in the range of 2 to 3 inches depending on the engine.

Pete

Thanks Pete

 

[Freestyle]

I had a similar mystery a couple of years ago on one 8v92. It turned out to be a small leak in the oil cooler that was draining out the exhaust.

Hope your's is that simple.

Bruce
Freestyle
62 CPMY
Tampa

 

[ageless]

I had a similar mystery a couple of years ago on one 8v92. It turned out to be a small leak in the oil cooler that was draining out the exhaust.

Hope your's is that simple.

Bruce
Freestyle
62 CPMY
Tampa

Bruce, I ruled out the oil cooler when the sheen stopped with fuel valve off, sure hope its simple too