Diesel fumes in cockpit area

Ok, I have developed a theory here, which frankly causes me some concern.

I considered the possibility of a cable run, but it seems unlikely for 3 reasons:

- the cable runs do not originate in the engine compartment, or at least, they are fairly well sealed where they exit the engine compartment.
- the sooting is fairly uniform on both side, so it would have to be propagating similarly up both sides of the hull
- if the fumes originated in the exhaust system outside the engine compartment, they likely be mostly on the port side

So how would fumes get distributed from within the engine compartment and migrate forward to the v-berth, particularly the bulkhead panels, without appearing elsewhere in the cabin?

Answer: through the gap in the forward wall of the engine compartment just above the fuel tank, through which the fuel line passes.

I've never removed the cabin sole, but I suspect there is an open cavity with the water tank at the forward end and the fuel tank at the aft end. Fumes which entered into the gap at the aft end under mild pressure would migrate forward and exit on both sides just above the water tank, where there are openings into the areas under the steps below the helm and passenger seats. From there they would exit through the forward walls, leaving soot lines on the openings and hinge in the panels at the aft end of the v-berth.

So tell me I'm wrong, but otherwise I'm going to be checking for small leaks in my exhaust manifold and plugging up that gap in the forward wall of the engine compartment.
 
The "gap" between the underside of the cabin sole (at the back cabin wall) and the bottom of the hull (bilge) is more like a cavern than a gap.. Look down between the generator and the back wall of the cave, and you will see a 2 inch high opening into the bilge running the width of the cabin sole - the other side also... This needs to be stuffed with a strip of closed cell foam to contain engine noise (and fumes) from radiating forward - which project is on my winter hit list along with numerous others - such as labeling each of the myriad, anonymous fuses dangling from wires in the battery compartment, making a new dinette table top so that someone over 90 pounds can fit the rear seat, etc...

denny-o
 
Tuggin...Sorry, MER is a local shop who DOES do Yanmar Warranty work! 😀

I like the theory and it does make a lot of since...I wonder if there is some kind of vacuum created with the temp differences in the water and fuel tanks along the sole?

Would love to see pictures of the modifications and see if the boat gets a little warmer.

Thanks again, Hope Everyone has a great Christmas!

Drew
 
:shock:

How many of you have the 110hp Yanmars that are noticing this issue?
 
Add me to the list. (Snug Tug, hull #25 with the Yanmar 110 hp engine, has some soot staining in the v-berth area at the seams in the plywood behind the fuzzy cloth.)

I've always thought that this was caused by some exhaust (with some soot) getting into the cabin from outside and then being pulled into the interior cavities of the boat by the engine air intake. Long runs at low RPM can cause the engine to run a little dirty unless it is periodically burned off at higher loads and temperatures, so a dirty running engine can magnify this especially if run with an open cockpit door and/or adverse wind conditions that let exhaust fumes into the cabin. Any engine problems that cause it to produce more soot in the exhaust will also aggravate this situation.

I also have to clean the transom from time to time as the exhaust (and soot) stains the white lettering back there. There is NO visible soot in exhaust while the boat is running, but the accumulation over time indicates that some is being produced. This is not unusual for a diesel. (The newer electronically controlled engines run cleaner than the mechanically injected ones, like the Yanmar 110 hp. I still like the mechanical injection better anyway!)

One thing I don't understand from the earlier discussions is the direction of flow. I.E. The engine compartment should have a NEGATIVE pressure due to the high volume air intake to the engine, especially on early hull numbers, such as mine, that do not have side vents in the hull. This negative pressure, or suction, would actually pull soot from the outside exhaust into the cabin through open windows or an open cockpit door and then pull it through all the open spaces in the boat that connect the cabin to the engine compartment as described by others. Thus the flow direction should be from the cabin into the engine compartment not the other way around as most people have theorized. The soot on the fuzzy cloth is filtered out of the air as it passes through the cloth. Maybe someone could try to trace the airflow with a smoke source of some kind (no flames, please, we don't want a fire!) around the openings in the cabin while the engine is running at high rpm with the engine compartment closed. I may investigate this myself but at the moment the boat is in Fla. and I'm up north until sometime later in January.

Adding engine compartment vents on the side of the boat like later hull numbers have may alleviate this somewhat as the intake air would be drawn in there instead of through the cabin and the pathways connecting the cabin to the engine compartment. Sealing those connecting pathways should also help.

Okay Andrew, now we need a professional assessment of all these crazy theories we are generating here on this discussion forum!!
 
For any of you who would like to "smoke test" the air flow between the cabin area and the bilge or engine room or any other combination, don't use smoke. Use talcum powder in a turkey baster and just puff out the talc using the bulb of the baster. We used to do this when were looking for water leaks in automobile T-tops and Moon Roofs back in my body shop days. We would pressurize the cars interior by closing all of the windows and turning the climate control blower fan on high. Then while sitting in the car we would puff the talc around any areas we suspected might be leaking water and you could often watch the talc as it exited the area of the leak, if not you could find the tell tale trail of talc left on the exterior of the car. It worked every time with no risk of fire and no damaging smell or residue.

If the air exchange is significant enough you should easily be able to watch which way the air is flowing under the various conditions which are being described.

Eric
 
Andrew -

Add Bay Ranger (Hull#43) to the list of R-25s with the 110hp Yanmars experiencing soot on the v-berth bulkhead covering . I just figured it was mold or mildew until I read this string. I haven't noticed any excess soot on the transom or in the engine compartment. I'm not smart enough to offer any new theories on the subject, but will continue to follow the topic with great interest. I have also enjoyed the great names given to the liner material, such as monkey fuzz, and fur!
 
Ok, Ok, time for a retired college professor, historian,Ph.D, (knows nothing, right?) to splice here.

This is beginning to sound like the ancient alchemy debate, or somethiing from CS Lewis, or a Harry Potter debate in class...really, Andrew...where are you on this? Time for the factory to step in with expertise, right?

As the debate stands how, I think I will call NASA...there will be out of work people there to help shortly.

terraplane
 
I continue to follow this thread with interest. It seems that many of the vessels that are having this issue reside in colder climates. As I stated in a prior post, we never had issues like this on Solitude. While this may be because of living in the desert we ran with all of the windows open most of the time.

However, after reading through all of threads a couple of times this evening, one stuck in my head. That was from Drew on R' Dragon. He wrote:

"The sooting I am talking about was up in the berth fur. It begin to disolor and after a bit more, became all out black! for us it was right at the joints were the house meets the hull along the sides and the curve of the bow. Also along the panels behind (in front of?) the helm and Nav seat. There is a seam there that has turned black. Supposition is that the exhaust followed a cable run and was coming out there."

The part that I find interesting here is the fact that he said it was at the seam of "the house meets the hull". Could this in fact be black mold growing. I am not sure how many people are aware as to how the deck is joined to the hull. The deck is simply set down on the hull and then riveted to the hull. An adhesive is then injected into the gap all the way around. If there is even the smallest gap, moisture will get in. Now think about this, what is the wettest area of your boat? The bow when pounding through seas. Could you be getting a small amount of water in through this gap? Left unchecked, it will eventually start to mold.

We now keep Karma in the PNW. Within the first couple of days we noticed the large amount of condensation that we accumulate below decks. We have since been leaving one or two of the hatches in the vent position. Another thing is we do not have a wallas stove nor a diesel heater. We use electric heat. Anyone from the north knows that electric heat is bad for wood furniture as it dries the air as it warms it. Could it be that these small leaks along with using a heat source that creates moisture could actually be causing a black mold problem?

If you are so inclined, I would pull the rub rail off and make sure that that the seam is sealed properly.

One thing I have done on Karma the last four weeks is identify every area that air was flowing from the bilge into the cabin. When it is in the teens outside, this is not hard to do! Just feel for the cold air blowing in.

Like Drew, I do not claim to be a mechanic but I do have a tendency to over analyze things......
 
I agree with Snug Tug's analysis. If the engine compartment has a negative pressure created from the engine how can soot get into the cabin. Could there be a back draft from the prevailing winds or possibly an inflatible on swim platform capturing the diesel exhaust for transfer thru an open door to the cabin.

Our Sea Ray (gas powered) has a bilge blower. Would a bilge blower added to the engine compartment power vent any soot in the air harmlessly to the outside?

I have not noticed any sooting (yet)in Tuggin Aweigh--110 hp yanmar. I have my fingers crossed.

What are your thoughts?
Tuggin Aweigh
 
David,
Good thoughts...It is nice to have more than 1 mind to analyze these things! I am afraid of pulling the rubrail, but may need to look at this. As I sit here taking a mental break from my job, I am almost wondering if there are not 2 problems occuring....Mold and Engine exhaust...we know that was a problem and the proof:

I spoke with the engine shop yesterday. They took pictures of the monkey hair/fur/fuzzy stuff and sent to Yanmar along with all of the exhaust elbow information. Yanmar must have felt "they caused some of it" because they are ponying up some money to clean or replace the damaged areas within the v-berth.

Merry Christmas to all, and to all great Tuggin!
Drew

PS: Tuggin, we almost never run with the cabin door open (Momma says it's too loud :? ) Never had a Dink on the swim platform and honestly the most time we spend under 3kRPMs is going in or out of the marina 😉
 
We noted these symptoms from our experience on the Laurie Ann on this issue:
1. Our soot problem happened very suddenly.
2. The sooting began after 500 engine hours and 24 months of cruising.
3. Half of our use was in the midwest and southeast; half in the Pacific Northwest
4. The characteristics of the black staining was not mold, it was smoke.
5. Our boat does not have full cockpit enclosure and therefore the engine air take that comes from the inside of the cockpit (not the cabin) was not restricted and therefore not an issue. If you did not know, on the early boats before the installation of the side vents, air was deliberately designed to be come from the cockpit in the gap between the hull and the cockpit liner. The Livingston engineering is very clever here, you can locate the gap by feeling under the gunnels and above the cockpit liner.
6. We agreed to the addition of the side vents for more air ventilation but they create a circulation pattern inside the engine compartment.
7. Since the rebuild of the turbo and a new water exhaust, the performance of the Yanmar 110 has been incredible
8. We have no mold issues because we keep heat boat all the time when the temperature is before 40 degrees.

What we have learned from this: do a better job on maintaining the engine system and using it properly. We have been very pleased with the factory's response on this issue.
 
RDragon":1rk4ofkp said:
We saw some of what Dave mentioned...Discoloration on swim platform etc...Came right off with Elbow grease :? The sooting I am talking about was up in the berth fur. It begin to disolor and after a bit more, became all out black! for us it was right at the joints were the house meets the hull along the sides and the curve of the bow. Also along the panels behind (in front of?) the helm and Nav seat. There is a seam there that has turned black. Supposition is that the exhaust followed a cable run and was coming out there. :cry:

Drew
Click to expand...

Hmmmm -- this means engine exhaust gases are leaking into the engine hold/bay. This should NOT be happening as all exhaust SHOULD exit through the exhaust tubing and to the stern port water-level outlet on the R25.

I'm now confused.... 🙁
 
Baz...
Dont be confused! We had a bad cast on the exhaust mixing elbow, which did not allow the seal to do it's job, so we were getting small amount of exhuast into the engine compartment and further into the boat. Since the replacement and the new seals, all is well. 😀

Merry Christmas,
Drew
 
I'd really like to get to the bottom of this mystery, and it would help if we could sort out some facts from all of the notes that have been entered.

First of all, lets separate the "sooting" issue from everything else (cockpit fumes, stains on the transom, etc.). A significant number of people have reported what appears to be the exact same thing I have: black "sooting" on the "mouse fur" at the seams of the V-berth bulkhead panels. The most reliable report so far suggests that this may be a consequence of some minor leaks in the exhaust system. While I accept that normally there would be negative pressure in the engine compartment, I don't really see how that would create "sooting" up forward. We run with hatches closed most of the time, and the normal interior air in the cabin wouldn't have this kind of soot. But I wonder if at times (starting, idling, backing, etc.) there might not be a reversal of the pressure that would cause air in the engine compartment to vent forward. I've already suggested the route that could take (through the gap at the forward end of the engine compartment, over the fuel and water tanks, and out through the bulkhead panels).

As far as I can tell, everyone who has reported this has a Yanmar, and they appear to be the older models with no side air intakes to the engine compartment. It would be good to confirm this, because it might help to demonstrate some combination of exhaust leaks with positive pressure in the engine compartment.

I'd like to request that everyone who has observed the symptoms of "sooting" send me a message with the following information:
- Model year
- Where vessel is operated
- Type of engine (mfr and hp)
- Engine hours
- Whether or not there are side air intakes for the engine compartment
- Location of sooting
- Severity of sooting (on a scale of 1-10, where 1 is barely noticeable and 10 is black)
- How long sooting has been evident

For example, in my case:
- 2007 R25
- Pacific NW (BC)
- Yanmar 125
- 260 hours
- No side air intakes
- Sooting on center seams of V-berth bulkhead panels
- Severity 5
- Since purchase (16 months)

I'll compile this information, report it here, and pass it along to Ranger.
 
Good Day Everyone,

I appreciate everyones thoughts on what this could be from. Please send "Me" the information Ram has requested and Ranger Tugs will investigate this issue a bit more. We do not think it is from the engine exhaust. We do know that at least 99% of the issues reported are all people with the older "non common rail" engines (Yanmar 100hp, 110hp, 125hp) They do smoke more. No way around this. Once again if you would like to submit information please send it directly to me and I will pass it on to the correct people. Would be preferred if you sent the information directly to my email. andrewcustis@rangertugs.com
 
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