Mechanical Question....

Maine Sail · Feb 19, 2008

Rich that's good info....

I learn something new every day here!! This is a clear example of why I don't completely trust even marine experts such as Westerbeke Corporation, Yanmar and or Nigel Calder!Rich perhaps "ummmm Sorry Maine, what you state is totally unsubstantiated." is a bit strong?I quote Calder here:When referring to a Primary filter:"If this is the only filter, a primary filter MUST be installed. (Figures 8-6A and B). This needs to be mounted between the fuel tank and the lift pump, not after the lift pump because any water in the fuel supply that passes through a lift pump gets broken up into small droplets that are hard to filter out." I quote Westerbeke Corporation here:"A primary fuel/water separator should be installed in the fuel supply line between the fuel tank and the engine/generator to help remove contaminants in the fuel before the fuel reachesthe engine mounted fuel lift pump."A link to the Yanmar site that also agrees with Westerbeke & Calder.http://www.yanmarhelp.com/i_fuel.htmMy "unsubstantiated" data comes from folks who I would hope I can fully trust such as my engine manufacturer! It's too bad these guys at Yanmar and Westerbeke just don't get it.What Rich says makes total sense but having owned a boat with a pump set up as he describes you need to be aware that the screen on the fuel lift pump can become clogged in rough weather, if you have sediment in your old tanks, which many old boats do. Even after spending $225.00 of fuel polishing my fuel pumps screen still clogged two months later (note: this was not the pump itself clogging but the pre-screen). After reading Rich's info it's totally plausible that my screen was already 95% clogged before I had the fuel polished. On that boat I did move the lift pump to "between the primary and secondary" and never again had a problem. Perhaps I should have left it where it was? I still think I'll leave it where it is, on my current boat, seeing as it's worked well on this boat for 2800 engine hours of run time, Westerbeke recommends it and I change my fuel filters every season or if the needle of the vacuum gauge moves up and of the pin.P.S. Rich, was the description, or my entire premise of the post, about the vacuum gauge correct in that the lift pump needs to suck "from" in order for it to work correctly because that was my entire point. I always check my vacuum gauge under power at cruise RPM. Is this not a fast enough RPM for it to be effective? To quote myself and my entire point:"Vacuum gauges are a great addition but they do need to be installed correctly to give good data.."Is this NOT correct??

Deadline · Feb 19, 2008

Go beyond fuel lines...

Typical starvation shutdown is due to the mixing elbow coking up and starving the engine of raw water. When was the last time it was changed?

T37 Phil · Feb 20, 2008

delta P

RichI could see how a pump might operate differently in 'push' vs 'pull' mode. But the filter is going to see the same differential pressure regardless of where you put the pump. Why would the filter be more efficient one way or the other?As I believe you stated, or almost stated, one reason for putting the pump after the filter is that the vacuum drawn (as read on a gauge) is a measure of how clogged the filter is and when it should be changed. But why couldn't you put the pump before the filter and measure the positive pressure required to push fuel through the filter. I suspect the answer to that question is related to what you'll answer to the first part.In any case, the boat I am looking at buying has a Westerbeke 50 with the pump and vacuum gauge after the filter. The owner is selling it as a feature. I never considered that it might be a negative.

Bryce22345 · Feb 20, 2008

water

replace the o-ring on the fuel cap.Bryce

Don S/V ILLusion · Feb 20, 2008

water in fuel tank

PaulI think the most common cause of water in the tank is a faulty o-ring on the fill cap which allows water to pour in. Even a lot of condensation wouldn't account for the amount you said he found.It is generally a good ide to periodically sample the bottom of the tank to see what is there. If you have any of the common pumps typically used to suck lube oil out of a dip stick tube, just insert same in the gage hole or other fitting and pump from the bottom.

r.w.landau · Feb 20, 2008

Paul, where is your tank vent located?

If it is in a location that is open to rough water, the next question is have you been sailing some rough water?4 liters is more than a gallon. That is alot of water unless you live in the pacific northwest

. Then it is probably is a bad "o" ring.r.w.landau

higgs · Feb 20, 2008

o ring on cap

That would certainly be the first suspicious place and is certainly a cheap fix. My old Irwin used to have a cap with an imperfection in the threads that sometimes would feel like it was tight, but if a jiggled it with the key, it would then tighten up.The vent is certainly a possiblity, but if you have had the boat for a while, not likely, unless you just recently took a knock down on that side.

higgs · Feb 20, 2008

Glad you are up and running

Not much you can do a this point but try to determine if the vent could have been the culprit, double check your fill cap after you fuel, and wait and see.

RichH · Feb 20, 2008

A one by one response.

"If this is the only filter, a primary filter MUST be installed. (Figures 8-6A and B). This needs to be mounted between the fuel tank and the lift pump, not after the lift pump because any water in the fuel supply that passes through a lift pump gets broken up into small droplets that are hard to filter out." REPLY *** what Nigel is referring to is ***free water eject*** from the fuel system - not filters nor filtration. If the free water goes through the pump it can re-emulsIfy --- larger 'particles of free water getting 'agitated' into smaller particles of free water. In this case *free water removal* is correct ... as this 'phase separation' is done before such water/oil mixtures get to a pump where the pump action mixes the 2 phases into a quasi-homogenized mix. What Nigel is NOT making clear and may be confused about is the difference between a water separator and a filter .... two separate and distinct jobs. A separator is simply any large chamber of sufficient high volume or low flow that will allow liquid water to settle to the bottom of the separator housing by 'gravimetric settling', etc. ************My assumption is that he clearly (and correctly) is stating that the fuel filters should not SEE nor come in contact with any water******* ... as the typical fuel filter media is NOT compatible with water ... if in contact with water will over long term --- soften (digest) and become weak and will eventually break. My guess he is also implying a specialized filter made of hydrophobic/'oleophillic' media that allows oil to pass but blocks the water and sends/sheds the water to a separate sump where the water will later be drained. You dont usually see a compound separator on small boats ... although they are available from manufacturers such as Racor, etc.: ... liquid-liquid coalescing filters, water blocking filters, water absorbing filters or combinations. I quote Westerbeke Corporation here:"A primary fuel/water separator should be installed in the fuel supply line between the fuel tank and the engine/generator to help remove contaminants in the fuel before the fuel reachesthe engine mounted fuel lift pump." REPLY **** operative word here is 'may' and refers to fuel/water ****SEPARATOR*** (not filter) .... air bubble removal pot, water removal or 'drop-out' pot. A separator is not a filter in a particulate removal device. A separator is a phase removal device, although 'specialized' filters can be used as separators. A link to the Yanmar site that also agrees with Westerbeke & Calder.Link submitted by authorMy "unsubstantiated" data comes from folks who I would hope I can fully trust such as my engine manufacturer! It's too bad these guys at Yanmar and Westerbeke just don't get it.REPLY **** I offer that you may be misreading the Yanmar and Westerbeake data .... *** separator is not a filter**** although a filter with the appropriate filter media may be a separator. What Rich says makes total sense but having owned a boat with a pump set up as he describes you need to be aware that the screen on the fuel lift pump can become clogged in rough weather, if you have sediment in your old tanks, which many old boats do. Even after spending $225.00 of fuel polishing my fuel pumps screen still clogged two months later (note: this was not the pump itself clogging but the pre-screen). REPLY **** Fuel polishing should never be a substitute for tank cleaning. Only by physical mechanical scrubbing (or equivalent) the biological resins and biofilms (the probable principal nucleation sites for the GROWTH of particles in diesel fuel tanks) from the walls of a fouled tank will a tank be prevented from 'particle storms' when a partial segment of the resinous biofilm breaks loose from the walls. Polishing a fouled tank will only clean the oil in the tank but hasnt enough velocity to mechanically remove the deposition of films/resins/agglomerated particles adhering to the walls. The cellular decomposition of dead cells into fragments is probably the means/mechanism by which the 'films' weaken and break loose. Polishing (recirculation polishing) is only valid to prevent or continually remove the nucleation sites/fungal spores/bacteria and spores that cause the fouling; plus, if the polishing system is onboard and is correctly designed for 'high mass rate turnover' (ie.: turns-over the entire tank contents every 60 minutes, etc.) will very quickly restore the particle burden in the oil back to 'normal' ranges for the secondary/primary filter to operate without rapid plugging. Polishing a fouled fuel tank is wasteful and only only cleans the oil, not the tank walls which are the REAL problem. Simple speak: if the tank is clean and routinely maintained so that the resident particles are low and kept low, the tank walls are clean (free of resin forming bacteria/fungi) there will be very decreased chance of any particles forming (small particles 'agglomerating' into larger particles ... which agglomerate and grow in to even larger particles ....) .... and the filters wont be 'challenged' with a huge amount of particles. A filter that is plugging is only doing its job but more importantly is telling you that you have a DIRTY TANK with walls that are 'growing particles'. A plugged filter is a SYMPTOM of a dirty tank that desparately needs to be scrubbed out. After reading Rich's info it's totally plausible that my screen was already 95% clogged before I had the fuel polished. On that boat I did move the lift pump to "between the primary and secondary" and never again had a problem. Perhaps I should have left it where it was? REPLY ***** Probably should have scrubbed out the tank, discarded the fouled oil, replaced with new oil and THEN polished the tank.

I still think I'll leave it where it is, on my current boat, seeing as it's worked well on this boat for 2800 engine hours of run time, Westerbeke recommends it and I change my fuel filters every season or if the needle of the vacuum gauge moves up and of the pin.REPLY ***** most fuel filters use a resinated cellulosic filter media from essentially ONE world source. The resination process is not 100% accurate to cover the cellulose fibers, cellulose digests in the long term presence of WATER .... thats why the recommendation to change yearly at a minimum because after ~ 1 year if the oil has any water (free or emuslified water) the filter media ...... will begin to FALL APART. P.S. Rich, was the description, or my entire premise of the post, about the vacuum gauge correct in that the lift pump needs to suck "from" in order for it to work correctly because that was my entire point. I always check my vacuum gauge under power at cruise RPM. Is this not a fast enough RPM for it to be effective? **** I use WOT (maximum fuel draw through the filters) as a reference, its good enough to check at some 'benchmark' RPM .... any relatively high rpm near your cruising rpm is perfect. Checking the gages when the engine is at idle or at some rpm different than what you establish as the 'benchmark' doesnt work. To quote myself and my entire point:"Vacuum gauges are a great addition but they do need to be installed correctly to give good data.."REPLY *****Totally totally agree. The essence of both our postings and the conventional wisdom of filter operation is to use a GAGE to know when to change the filter. Not only will the gage tell you WHEN to change, it will also indicate if your tank is becoming fouled (rapid build of gage reading), if the gage starts to 'decrease' in reference to your benchmark rpm - then you suspect a filter that has broken it pleats (water disgestion of the filter media, fatigue of the pleats due to 'pump vibrations'), etc. or is otherwise 'bypassing' particles (loose/broken internal O-ring, etc.). Inotherwords you will have absolutely NO idea what the filter is doing, etc. if you dont have a gage installed. It really doesnt matter which type of system (pressure or vacuum feed), the moral of the whole story is: CLEAN OUT THE TANK every now and then, use a GAGE on the filter so you KNOW how its operating (not waiting until the engine shuts down because the filter is plugged), dont buy your fuel from a seldom used marina but rather a high turnover depot (used by commercial fishermen, etc.) or jug it in from a truckstop, etc. ... so you know its FRESH and relatively water FREE. Lastly, dont depend on a filter to do your routine maintenance inside the tank. ;-)

sailaway78 · Feb 20, 2008

Check the vent plumbing

Some friends of mine had a problem similar to this a couple of years ago. The boat was a nearly new Hunter 33. The factory plumbing from the tank vent to the tank, went straight from the vent, "down" to the tank. Every time they got the boat heeled in a certain way, or some water splashing just right, they got a shot into the fuel tank. Hunter actually sent out a service bulletin, as this was apparently not a one time thing on these boats. So, make sure you have a loop in the vent line, which is quite a bit higher than the vent itself.

RichH · Feb 20, 2008

PaulH --- several causes of water in fuel.

Possibilities1. as others already mentioned: bad O-ring on fill plug. 2. OLD fuel that has become fully saturated with water (water vapor, etc.) ..... small marinas are typically such sources of OLD fuel. 3. the fuel depot that you buy your fuel from has a leakey tank .... water entering the tank from an underground crack, etc.4. so-called Bio-Diesel made with a % of 'reclaimed oil ... ie:. re-refined used cooking oil'.

Ross · Feb 20, 2008

I would at the least install a Tee trap in the vent line

before the loop. In that way any water entering the vent would drain into the trap and accumulate in a drainable tank. I vented my tank into the stern rail so as to avoid a spill if I over filled the tank. The end of the vent line is about a foot above deck level.

RichH · Feb 20, 2008

Phil - not a negative.

a gage to monitor any filters performance is a real PLUS. Well designed pressure feed filtration will (mostly) allow the deposition of the debris ON the surface of the media (rarely deeper than 5% of the thickness of the media) and with 'hard' particles this will begin to form a 'cake' of debris which sometimes will act as the filter media itself (cake of debris doing the actual filtration), etc. In vacuum filtration generally the 'cake' or deposition forms INSIDE the filter media blinding the 'open flow pathways' faster than when the debris is captured on or near the surface.

r.w.landau · Feb 20, 2008

Paul, as always, let us know what you find.

We all have advice, it is when someone reports that advice is confirmed. You have been great with your feed back. It really does help us all!thanks,r.w.landau

Maine Sail · Feb 20, 2008

Rich,

Rich,Quote Rich: "What Nigel is NOT making clear and may be confused about is the difference between a water separator and a filter .... two separate and distinct jobs." Answer: He actually makes it quite clear that when he refers to a primary filter he is referring to a filter that both filters and separates water such as a Racor 500 series in fact there is one pictured right on the same page. You can read it for yourself on page 252 of the "Boat Owners Electrical and Mechanical Manual"!I quote Westerbeke Corporation here:"A primary fuel/water separator should be installed in the fuel supply line between the fuel tank and the engine/generator to help remove contaminants in the fuel before the fuel reaches the engine mounted fuel lift pump."Quote Rich:REPLY **** operative word here is 'may' and refers to fuel/water ****SEPARATOR*** (not filter) .... air bubble removal pot, water removal or 'drop-out' pot. A separator is not a filter in a particulate removal device. A separator is a phase removal device, although 'specialized' filters can be used as separators.Answer: Sorry there is no "operative word", "may", in the above statement by Westerbeke the word they used is "should". Westerbeke is also quite clear on this, and shows a picture on page 27 of the installation manual that says "Fuel Filter/Water Separator" and the illustration looks an awful lot like a Racor 500 series.. You can view that here on pg. 27: http://www.westerbeke.com/technical/installation_manual/installation_manual.pdf"My "unsubstantiated" data comes from folks who I would hope I can fully trust such as my engine manufacturer! It's too bad these guys at Yanmar and Westerbeke just don't get it."Quote Rich:REPLY **** I offer that you may be misreading the Yanmar and Westerbeake data.... *** separator is not a filter**** although a filter with the appropriate filter media may be a separator.Answer: Yanmar calls it an: "E) Primary Fuel Filter/Water Trap". http://www.yanmarhelp.com/i_fuel.htm While your offer is nice Rich I don't think I misread anything and I've given you the links and sources for everything. I'm not making this stuff up.All of the above references, Calder, Westerbeke & Yanmar, refer specifically to Fuel Filter/Water Separator combination units such as the Racor style not straight water separators..

Joe · Feb 20, 2008

re: RichH and Maine Sail......

Zzzzzzzzzzzzzzzzz...... MIT vs CalPoly

Maine Sail · Feb 20, 2008

Sorry to bore you joe..

Sorry to bore you Joe!!! But it's more like Ralph Kramden & Ed Norton....;D