Dual fuel filters

[sunchaser]

Codger

Do you have a fuel filter vacuum gauge read out at your helm? For some that is a nicety so that if vacuum increases to a "concern" number you can flip the valve to the other filter before the engine stumbles.

We've never had one iota of vacuum show up on our 900s. Which should be the case given our low fuel burn rate. On planing vessels using 15GPH+ per side, seeing a vacuum increase is understandable.

 

[BonesD]

Codger, the vacuum info is very interesting. First I have heard of that.
My fuel consumption as stated at beginning of post is marginal. Gallon per hour and about 2 1/2 gallons on the return so I wonder if I also would show little to no vacuum. If that’s the case I will just buy another Racor and a valve. Much cheaper than investing $800 plus dollars for the factory set up with gauge.

 

[syjos]

Here are pictures of Sandpipers fuel selection panel.

The top two valves labeled "Tank Selection" select which tank fuel is drawn from.

The valves below the Racors labeled "To" selects where the fuel goes after filtration - Engine, Generator or Pump.

The valves at the bottom of the panel selects where the fuel gets returned by engine, on left and generator on the right.

The narrow panel to the left has valves to select where the fuel goes after the pump - Starboard tank, Port tank or to the engine for priming. The pump is used to prime the engine, remove fuel from the tanks sumps and to move fuel from one tank to the other. The little spigot at the bottom is to pump diesel into a container in case I need fuel to top up the Racor after element change.

The panel is designed and labeled for me to use when I'm really old and forgetful. It's simple to figure out. The panel is hinged on the left to allow access to the back of the panel.

The plumbing diagram is at post #17

 

[BonesD]

Very clean install.

I have a question. Suppose you are cruising along and the engine begins to sag from lack of fuel, do you throttle back immediately and race to the switch over valve or shut the engine down completely so as not to exhaust the fuel supply that remains in the lines?
Shutting something down that may not start again is a bit contrary to my instincts but if I knew for sure it was fuel starvation I guess I would. Instinct might be to briefly throttle up to try and diagnose the issue.
In my case I would have to pull up the engine covers in the pilot house to reach the switch over valve (when I get one).

 

[syjos]

Very clean install.

I have a question. Suppose you are cruising along and the engine begins to sag from lack of fuel, do you throttle back immediately and race to the switch over valve or shut the engine down completely so as not to exhaust the fuel supply that remains in the lines?
Shutting something down that may not start again is a bit contrary to my instincts but if I knew for sure it was fuel starvation I guess I would. Instinct might be to briefly throttle up to try and diagnose the issue.
In my case I would have to pull up the engine covers in the pilot house to reach the switch over valve (when I get one).

I've actually never had a fuel filter clogging problem underway. I do hourly engine room inspection and look at the Racor vacuum gauges at that time.

If the engine started acting up from a clogged filter, I could run down to the engine room in less than a minute and select the other Racor. I would not turn off the engine.

 

[BonesD]

��

 

[mvweebles]

30+ years ago, a girlfriend and I moved from Atlanta to San Francisco. I was a newbie who'd recently caught the boat bug from her dad who lived on an old Chris Craft in Marina del Rey. Housing in SF was expensive so we decided to buy a boat and liveaboard. We found a pristine Uniflite 42 in Newport Beach, over 400 miles south of SF. We hired a licensed captain to deliver with myself as crew.

We were pretty broke so had to make choices. One of which was putting on spare fuel filters. The boat had 555 Cummins and some sort of fuel filters where the elements were over $100 for each engine. Decided not to buy spares, but did change out to new ones before leaving.

I gotta tell you, I was scared. Even long before the internet, there were stories of Pt Conception and mixing up crud in the fuel system leading to certain death due to clogged fuel system. This is pre-GPS, when you'd get a lat/long off the Loran then plot on a chart. Lighthouses were still useful.

Heading on long trips like this, you can easily end up quite a ways offshore. The fuel system never burped, but I had to think to myself "what would a filter be worth out here if it the system did clog?" Even though I didn't have a lot of money, I wished like hell that I had spares aboard.

Long story to provide context to why I'm so concerned about fuel delivery, and I suspect Codger has a similar story. All I can say is I won't leave port without dual filters that can be hot swapped while underway. I've never had to do it, though when I delivered, I did it a few times as a general service while underway. Also as a delivery skipper, I found out how difficult it was to figure out DIY upgrades like fuel valving.

The above said, hats off to Syjos. Beautiful installation and I really like that he took the time to have labels made. I can tell others from experience that he had many, many hours into his system. Perhaps over 100 hours I'd you consider the design and sourcing of parts and construction of the bread board to which its mounted. Bravo! Well done.

Peter

 

[syjos]

When we bought NWD it had a single Racor 500 for each engine, poorly located to service. Rather than replace them with the $$$ dual setup from Racor, we configured our own dual setup. I have to throw two valves to switch, instead of one, but can switch underway if I ever need to. See post #29 for a pic and discussion of what we did for our fuel manifold here https://www.trawlerforum.com/forums/s25/davis-42-light-refit-rehab-40532-2.html

There are smaller Racors, like the one I have for our gensete. It is an 120AS, for diesel and rated at 15 gph. I've never seen a dual setup for them from the manufacturer.

If the money wasn't as big of a deal at the time, in retrospect it would look/be nicer to have bought the dual 500 setup. I'm not a Racor advocate; they work for the purpose and the boat came with them. Rebuilt kits were cheap and they are easy to work on/maintain.

That's a very nice system. I'm reading the rest of your refit thread. Good job! I like reading about well documented projects that are accompanied by good pictures.

 

[syjos]

Peter

View attachment 101556

View attachment 101557

Nice diagram. I'm still a pencil and paper guy. What did you use to make the diagram of your fuel setup?

 

[Codger2]

Do you have a fuel filter vacuum gauge read out at your helm?......... On planing vessels using 15GPH+ per side, seeing a vacuum increase is understandable.

I don't have a gauge at the helm at the present time as my experience with this boat really doesn't demand it. The trips these days are short, no more than 3 hours/ trip and the tattle tale pointer on the Duel Racors keeps me informed after each trip.

The photo below shows me burning 15 gals/side at 2600 rpm. WOT is 3300 rpm but I have never run the boat that fast to see what the burn is. (Edit: I did run the boat at 3200 rpm on her sea trial but I didn't have the Maretron Fuel Management System at that time, so I really don't have a burn figure for that throttle setting.)

 

[mvweebles]

Nice diagram. I'm still a pencil and paper guy. What did you use to make the diagram of your fuel setup?

PowerPoint. I'm a management consultant in real life. I live and die by PPT slides and XLS charts

 

[Codger2]

My fuel consumption as stated at beginning of post is marginal. Gallon per hour and about 2 1/2 gallons on the return so I wonder if I also would show little to no vacuum. If that’s the case I will just buy another Racor and a valve.

I would do the same if my fuel burn was that low.

 

[syjos]

The above said, hats off to Syjos. Beautiful installation and I really like that he took the time to have labels made. I can tell others from experience that he had many, many hours into his system. Perhaps over 100 hours I'd you consider the design and sourcing of parts and construction of the bread board to which its mounted. Bravo! Well done.

Peter

Thank you.

To be honest, the R&D was done on a clients dime. I had a request from a client who wanted to be able to switch the engine filter with the generator filter underway in case of fuel contamination. So I came up with this plumbing design and reconfigured his existing Racor 500's without them being on the panel. The valves were on a panel away from the Racors and required a lot of hose because the client did not want the Racors relocated.

When I bought Sandpiper, I fine tuned the design and made it simpler to use.

I've installed similar panels on several client's boats prior to my retirement.

 

[BonesD]

Has anyone with a craft that has low fuel consumption and a vacuum gauge like Codger described have the same results with no vacuum registering?

 

[syjos]

Has anyone with a craft that has low fuel consumption and a vacuum gauge like Codger described have the same results with no vacuum registering?

The gauges on my Racor 500's (60 GPH) sit on 0 for a long time after element change. It lifts off the 0 after about 100 hours.

I use 1.83 GPH

 

[mvweebles]

Has anyone with a craft that has low fuel consumption and a vacuum gauge like Codger described have the same results with no vacuum registering?

My Willard 36 had a 4.236 80hp diesel that burns around 1 gph. I recounted the story of running 75 hours straight from San Francisco to Ensenada, a distance of 500 nms. I definitely had vacuum come up into the yellow zone. Of course, 10+ year old diesel. So worst case scenario

 

[markpierce]

Having dual filters changeable at the flick of a switch is especially an advantage when the currently-used filter doesn't provide for cruising speed while underway.

 

[BonesD]

Where should a clean system be registering on the gauge?
Syjos,
It sounds like yours doesn’t start to register until the filter starts to foul a bit.
MV the same for yours.
Is that the gauge’s function to show the extra vacuum due to reduced flow?
I was thinking the other way around that the vacuum would be higher and drop due to blockage.

 

[markpierce]

The picture shown in post 47 was while the boat was at berth, not underway. Just a periodic filter change. Was too busy to take a photo during an underway change which didn't require other than moving a lever.

 

[syjos]

Where should a clean system be registering on the gauge?
Syjos,
It sounds like yours doesn’t start to register until the filter starts to foul a bit.
MV the same for yours.
Is that the gauge’s function to show the extra vacuum due to reduced flow?
I was thinking the other way around that the vacuum would be higher and drop due to blockage.

With a clean new element in a 60 GPH filter the 2 GPH engine does'nt draw enough fuel to register on the vacuum gauge.

The reading gets higher on the gauge as the element begins to accumulate debris.

The reading gets higher with the increased vacuum

 

[FF]

The folks blessed with a high mounted fuel tank that uses gravity to feed the engine may not see the gauge move till the filter is totally plugged.

 

[fractalphreak]

That's a very nice system. I'm reading the rest of your refit thread. Good job! I like reading about well documented projects that are accompanied by good pictures.

TY. Still rethinking a couple things, and wish I'd made more of a board like you have - labeling is difficult at the expense if seeing all the connections. Compared to what we started with though, I'm very pleased in how easy it is to manage the fuel system.

 

[fractalphreak]

With a clean new element in a 60 GPH filter the 2 GPH engine does'nt draw enough fuel to register on the vacuum gauge.

The reading gets higher on the gauge as the element begins to accumulate debris.

The reading gets higher with the increased vacuum

Our experience matches the others here. We have both engines routed through one Racor 500. After full throttle for short time about 75 hrs after a filter change noted a rise in vacuum for the first time. Thats twin Lehmans at 2400+ RPM for 10-15 min, so pulling maybe 10 or 12 gph instead of the normal 2. We had already noticed some fine particles of gunk in the bowl, and weren't surprised, I went ahead and changed the filter as I wanted to see just what was coming out of the tank. The accumulation in the filter was likely from remaining gunk in older fuel from some areas of the tank we hadn't completely cleaned. The amount of vacuum was low, I don't remember the exact reading but it was right near the beginning edge of the yellow.

The filter change in this case was absolutely not necessary, but done to satisfy my own curiosity on how our fuel system was doing.

At our normal cruising speed around 1400 rpm (6.5ish knots) the vacuum gauge doesn't come off the peg.

 

[BonesD]

Gotcha

 

[Xsbank]

Very nice upgrade! To me, this is a huge part of boating. Improving/fixing systems that were cheaply, quickly or just plain buckshee’d in order to get the boat out the door or the wire-nut fixes that become permanent so you can go on that day-trip. Boat systems are more like aircraft systems than car systems where there are all sorts of ways you can sink, blow up, catch fire, get jammed in machinery or just have a life-threatening system failure where you can’t just pull over. All that if you can manage to actually stay on the boat or out of the water.

Have a think about how much stuff can go wrong and how difficult it will be for others, who put their lives at risk, to rescue you all because you have a Mickey Mouse system on your boat that can do all the above to you and your blissfully unaware loved ones.


Covid Project number 342.

 

[fgarriso]

IMHO if you have a one main engine then dual racors is a MUST.

If you have twins then you could get by with one racor per engine.
In the one racor installation it would be possible to shut down one engine and still run on the other at reduced speed. But, I personally would not recommend it.

On GOTCHA we run 1800 gallons of fuel in four tanks. We have twin CAT 3406 engines set at 250 HP at 1600 RPM with a total fuel burn of 3-1/2 GAL/HR with 1400 RPM at 8.5 Kts. We have dual racors for port and stb engines with fuel return going back to selectable tanks. The engines also have dual selectable CAT filters on them at the engine. With this arrangement we can switch racors and/or CAT filters without shutting down the mains. This only works well if you have remote vacuum gauges at the helm. If not you have an engine going south as your first warning by then it is a scramble to have the first mate run into the engine room to switch filters. The remote gauges allow you to switch filters at the first sign of filter vacuum.

I have found that when the racors are getting plugged or have high vacuum they then to overflow or bypass into the CAT filters. When or if that happens you need to switch the racors and the CAT filters at the same time.

This arrangement has four filters per engine, and backup for everything. I know it cost little more to setup, but you don't have the 3 AM scramble.

As I said this is what we do and, it may not be the best but it works.

 

[Simi 60]

Has anyone with a craft that has low fuel consumption and a vacuum gauge like Codger described have the same results with no vacuum registering?

Have never seen ours go above zero in 4 years of cruising
Well, it did once when I moved the handle towards off just to see if it did register.

Dual 1000's but running as single and a spare.
NTA 855 Cummins pushing around 320 litres/hour through the system and burning 15 litres of it.

 

[diver dave]

Hmmm, I would opt for a low range differential mechanic gauge. Several reasons: a gauge normally sitting at zero gives me little confidence the plumbing is intact, if there is even a filter medium in place/intact, and if the gauge is stuck. Also, if you have fuel sitting higher that the gauge, you have already got a positive pressure on that vacuum gauge. I want to see some vacuum reading during any running condition.

 

[syjos]

If I want to see if the vacuum gauge is working, I close the valve to the fuel tank momentarily and watch the needle on the gauge rise.

 

[diver dave]

If I want to see if the vacuum gauge is working, I close the valve to the fuel tank momentarily and watch the needle on the gauge rise.

That’s true. I forgot one more though. If u either pick up a feed air leak or fuel runs out, that small vacuum reading goes away. But only if you are getting a reading.