Has anyone solved the Fischer Panda riddle?

[Rough Magic]

I would love to see a PowerPoint instruction.

[sainted]

I work for a Fischer Panda dealer, so I see a fair number of the beasts. Water intrusion is a common problem. Poor installations are made worse by the fp's tendency to turn backwards for a revolution or so after being shut off. Turning backwards can suck water from the exhaust back into the engine. Other than ensuring that the outfall from the exhaust goes as straight down possible, we know of no solution to this problem.

[Ferrari]

Remember it’s the Hot Exhaust Gases that mix with the Water to push it away.
Excessive cranking of the engine while it is Not Firing produces No Gases. IE No Pressure! Which means nothing to stop the water running back into the engine.
Leaving a reluctant starting engine after several long cranking attempts could be an invitation to water to enter the exhaust valves.
If your engine is a difficult starter better turn off the water supply until its running.
Better yet fix the engine starting problem.

[Simi 60]

Originally Posted by sainted

I work for a Fischer Panda dealer, so I see a fair number of the beasts. Water intrusion is a common problem. Poor installations are made worse by the fp's tendency to turn backwards for a revolution or so after being shut off. Turning backwards can suck water from the exhaust back into the engine. Other than ensuring that the outfall from the exhaust goes as straight down possible, we know of no solution to this problem.

I can think of one.

[JOHNMARDALL]

Originally Posted by Rough Magic

I would love to see a PowerPoint instruction.

Please email me at jmardall@comcast.net and I'll send the PowerPoint to you asap.

[JOHNMARDALL]

Originally Posted by Simi 60

I can think of one.

Have you tried an open hose vacuum breaker in the raw water line between the heat exchanger and the mixing elbow? In the "running backwards" situation you describe, that would have air pulling into the open exhaust valves rather than water. Of course, being from the shameless commerce division, I'm thinking of one of our ASDH anti-siphoning air vents.


All the best
John Mardall
Vetus Maxwell Boat Equipment

[Quietta]

Originally Posted by billknny

Waves hitting the hull hard enough at the exhaust outlet can force water up and over a fairly high lift without ever really syphoning. This can -- slowly, over time--fill the system to the point where the water level reaches the engine, and bad things happen. A few spoonfuls every once in a while can add up to a significant amount over a week's passage if the genset is not being run.

Good point: The exhaust for the generator doesn't have a protective shield ( it is the only outlet that doesn't have this, maybe because the water is already separated from the exhaust?) so the slapping effect of water over the exhaust outlet could be an issue.



The boat is a catamaran so angle of heel is probably not a factor.
It was my first time on a large cat and we did get some occasional waves smack the underside of the salon or the insides of the hulls with startling results. One wave that came up under the salon such a thump it managed to launch the 2.5kg fire extinguisher off its bracket on the dining table.

[Quietta]

Originally Posted by sainted

I work for a Fischer Panda dealer, so I see a fair number of the beasts. Water intrusion is a common problem. Poor installations are made worse by the fp's tendency to turn backwards for a revolution or so after being shut off. Turning backwards can suck water from the exhaust back into the engine. Other than ensuring that the outfall from the exhaust goes as straight down possible, we know of no solution to this problem.

Good point.

We discussed that the engine might hit the final compression stroke and spin backwards a partial revolution leaving the exhaust valve open providing the possibility for condensation from water in the muffler to form on the cylinder wall. We discounted this idea because it would affect all marine engines.



I never though that this might happen for multiple revolutions drawing back water directly into the exhaust.



Then engine is out of the boat so let the autopsy begin.

[shelleyWendert]

Treatment method and Prevention of Inlet Fault of genset


1, for the external influent, this kind of problem is generally preventable, that is, do a good job of generator protection, pipe waterproof treatment, such as into the generator to do a head, and leave a discharge valve, can often remove stagnant water;


2, cylinder pad damage, replace cylinder pad, repair kit;


3, the cylinder liner leakage, replace the cylinder sleeve rubber ring;


4, oil cooler leakage, pressure test treatment, find out the leak point for treatment or replacement;


5, water pump leakage, check the water seal, replace the pump repair kit;


6, the engine cylinder block ruptures, needs to carry on the repair or the replacement to the cylinder block;

[cruisehope]

John - I saw your comment above related to a FP water intrusion: Re: Has anyone solved the Fischer Panda riddle?
There are three main ways that water can get into a marine engine - a back up from the waterlock, a siphon from the intake side of the raw water system eventually filling the waterlock and causing a back up into the exhaust manifold, and a blown head gasket.
If you would like to contact me direct I will send you a PowerPoint and an interactive spreadsheet covering the first two of these issues and will then respond to any questions you have.

The waterlock was installed at about the same elevation as the bottom of the genset, but 7.5 feet away. I am on a sailboat and regularly heel over to 25deg. When I brought this issue up to the installer after I discovered water intrusion on the piston, valves, head, he blamed it on a leaking raw water pump. Any comments?
Can you please tell me how to reach you to get the interactive spreadsheets that you refer to.?

[Ocean Cowbuoy]

might be a silly question but would a check valve solve the problem?

[billdomb]

Any chance of water in the fuel itself?

[Breffni]

We used to plug a wooden rounded bung which was kept hanging at the exhaust outlet
right into the exhaust hole and that kept water from ever getting inside. Wooden rounded to fit the hole bung and a wooden mallet to tap it into exhaust outlet gently but firmly and never had any trouble with the issue.

[JOHNMARDALL]

Originally Posted by Ocean Cowbuoy

might be a silly question but would a check valve solve the problem?

Dear Cowbuoy (sic)

Far from being silly, I get that question frequently. The "rubber flappers" forming a part of many transom exhaust fittings are effectively check valves, however, we recommend relying on a gooseneck (high point) in the exhaust hose, with no valves, as that system only relies on geometry and gravity, which will not break and does not require human intervention. If installed on a monohull sailboat, the top of the gooseneck must be on or very near the centerline, so that it will not be overtopped when the boat is heeled.
All the best
John Mardall
Vetus Maxwell Boat Equipment.

[stargate]

A problem I have had on a vessel, was the intake thru hull fitting. It actually caused water to be forced up the intake line when the boat was moving ahead. Thus slowly filling the exhaust system and eventually into the generator engine causing it to hydraulic.
The solution was putting a valve just before the water pump to prevent this, and a sign to remember the valve. You had to open this valve to run the generator and close it when you shut it off.
It was a strange phenomena and only happen the one time before putting the valve there. The boat had run fine without one for a few years ?? It was strange, but it did happen.
Just food for thought