Fuel shut off valve

[paulga]

I'm planning to change racor filters and spin on filters later this week. I recall the first step is to shut off fuel. Is the yellow valve shown below the one? Turn it clockwise 90d shuts off the fuel? Are there any other valves to turn before ready to change the filters?

 

[Action]

Isn't that what the directions on the bottom of the mounting board indicate?

 

[paulga]

Thanks for confirming that's the only fuel shut off

 

[tiltrider1]

Actually, the instructions below say to turn the two 3way valves to the left to shut off the fuel. The yellow handles is labeled a bleed valve.

 

[twistedtree]

Actually, the instructions below say to turn the two 3way valves to the left to shut off the fuel. The yellow handles is labeled a bleed valve.

Right. This seems to be spelled out in the labels on the panel. If only all boats were so clearly set up. To summarize what it says:


- The Yellow handle valve is a bypass valve for use when you want to run the small aux pump to bleed the fuel systems.


- The three way valves below control the draw and return to/from the filters, with positions shown in the diagram. Right now it's set to use the #1 filter. Turn them to the Off position to change filters.


You have a really nicely set up and well documented/labeled fuel system.

 

[paulga]

Thanks for the explanation
So the "off" indicates fuel shutoff

I thought there was a single valve for shutoff

Right. This seems to be spelled out in the labels on the panel. If only all boats were so clearly set up. To summarize what it says:


- The Yellow handle valve is a bypass valve for use when you want to run the small aux pump to bleed the fuel systems.


- The three way valves below control the draw and return to/from the filters, with positions shown in the diagram. Right now it's set to use the #1 filter. Turn them to the Off position to change filters.


You have a really nicely set up and well documented/labeled fuel system.

 

[CharlieO.]

I like the labeling, everything I have is not labeled or mislabeled.

Turn the two Racor valves to the off position then your filters are isolated from the system.

There probably are original valves on your tanks also but not needed for this job, but is good to know where they are.

 

[paulga]

Thanks guys for your inputs.

The three way valve should also shut off fuel to the generator racor, right? the bleeding pump should also cover the generator racor.

I have highlighted a section of short fuel hose from the gen racor to the tank (starboard). what's the fuel flow direction in that hose?



(the oil pads were from last filter change)

 

[Bmarler]

It’s impossible to tell from here if the three way valves shut off the generator filter or not. I’d guess no though. The genset should operate independently.
It’s also tough to say if the priming pump services the genset filter. You just need to do a little sleuthing and see what hoses connect where so you can make sense of it all. It looks well laid out, so tracing them out should be easy.
Direction of flow on the hose you highlighted would be right to left if we’re looking at the front of the filter. The ports should be labeled.
It’s hard to tell, but the priming pump looks like it runs to that same area. That might be where it gets it supply. Again, you need to follow the hoses. Maybe make a little sketch of each connection and where it comes from.

 

[twistedtree]

Thanks guys for your inputs.

The three way valve should also shut off fuel to the generator racor, right? the bleeding pump should also cover the generator racor.

I have highlighted a section of short fuel hose from the gen racor to the tank (starboard). what's the fuel flow direction in that hose?

View attachment 143568

(the oil pads were from last filter change)

I think you are in the best position to answer these questions. We are all looking at the same things you are, but limited to the pictures you have posted. There are other people here with MT boats, but you need to keep in mind that every single boat is different. Many are different from the factory, and after 20+ years of ownership 100% of them have become different.


Trace your fuel lines, and you can answer these questions yourself, and probably with more accuracy than all of us looking at pictures. On your first question, just following the fuel lines and looking at the operating instructions gives you all the answers. It was actually remarkably well documented in the posted instructions. On your generator, look at where the filter hoses go. Look to see if there are IN and OUT indications on the filter housings as a way to confirm fuel flow. Will the filter be on the fuel flow that feeds the generator, or will it be on the fuel return to the tank? Look at how the bypass/primer pump is plumbed in. Does it bypass the generator filter? Does it push fuel through the generator to prime it, or does it only push fuel through the main engine(s)?


It's not that we don't want to help, but I think it's essential that you get practice and build confidence in figuring out some of this stuff yourself.

 

[paulga]

Last time I traced the lines but couldn't figure out the flow. So the fuel lines setup is not standardized. Thanks for the hints.

I think you are in the best position to answer these questions. We are all looking at the same things you are, but limited to the pictures you have posted. There are other people here with MT boats, but you need to keep in mind that every single boat is different. Many are different from the factory, and after 20+ years of ownership 100% of them have become different.


Trace your fuel lines, and you can answer these questions yourself, and probably with more accuracy than all of us looking at pictures. On your first question, just following the fuel lines and looking at the operating instructions gives you all the answers. It was actually remarkably well documented in the posted instructions. On your generator, look at where the filter hoses go. Look to see if there are IN and OUT indications on the filter housings as a way to confirm fuel flow. Will the filter be on the fuel flow that feeds the generator, or will it be on the fuel return to the tank? Look at how the bypass/primer pump is plumbed in. Does it bypass the generator filter? Does it push fuel through the generator to prime it, or does it only push fuel through the main engine(s)?


It's not that we don't want to help, but I think it's essential that you get practice and build confidence in figuring out some of this stuff yourself.

 

[ranger58sb]

Nice labeling. I think the pics indicate the 3-way valve does NOT interrupt flow to the genset.

Our dual Racor setups work differently; UP is OFF, DOWN is BOTH, and the other two positions (left and right) point to the active filter.

-Chris

 

[mvweebles]

OP - the labeling and directions on your system are indeed well above average. But that is a very low bar as most boats in our class have either lackluster original install, or DIY best-efforts that fall short (or both - DIY with lackluster results was what I replaced with me being the DIY tech 20-years ago). To my thinking, multi-way valves almost always lead to confusion. (EDIT - OP: Looks like you found a boat that was sold by a knowledgeable owner. Everything in your picture shows well-labeled and above-average install).

1. Racor Dual Filter housing. Expensive, but the manifold is very intuitive compared with a two single Racors with a 3-way valve between. I know, about the same, but not really.

2. Fuel manifold vs 3-way valves. Mine was a custom SS one, but nothing wrong with NPT plumbing fittings. Or Reverso makes a very nice one. Mine was built during Covid and I used the only valves I could find. Better would be the smaller-handles. These long handle ones interfere with each other.

We just arrived in La Paz, something like 900 nms from Ensenada where we started 2-1/2 weeks ago and over 130 engine hours. I've changed fuel tanks a few times while underway to trim the boat. Maybe I lost braincells in my mis-spent youth, but changing fuel tanks while underway needs to be simple and intuitive. I have never seen a system built on multiple valves pass muster for me. The LAST thing I want is to kill the engine and need to bleed it in the middle of a 24-hour run; well offshore.

That said, a notable shortcoming on my system (besides it could use additional labeling of the Walbro prime-pump and Groco transfer pump on left hand side) is fuel cannot be polished or transferred while underway because it uses the same manifold (and thereby the same tank pickups) as the engine. Higher end boats (Nordhavn et al) have a separate fuel supply and manifold/management system for transfer/polishing --- which is higher volume/flow than the engine supply.

Peter

 

[Cartouche]

I'm planning to change racor filters and spin on filters later this week. I recall the first step is to shut off fuel. Is the yellow valve shown below the one? Turn it clockwise 90d shuts off the fuel? Are there any other valves to turn before ready to change the filters?View attachment 143531

There should be shut offs at the tanks, if you are not sure DO NOT ATTEMPT THIS yourself

 

[paulga]

I searched around the fuel tanks, the only valves that could be the shut off are located near the gauge at the tank bottom near the forward bulkhead. Can someone with similar setups confirm?

Portside


Starboard


The thick blue hoses connect to the transfer pump:

 

[mgreen]

A comment about 3 way valves. They are not all created equal in how they work.

I bring this up because I saw somewhere that a person was using 6 way valves for their fuel system. The 6 way valves I saw, appeared to be similar to what I see in a HVAC Chilled Beam application. It is essentially two 3 way valves stacked on top of each other so you could not mess up supplying fuel from one tank without returning excess fuel to the same tank.

Most should have the ports labeled A, B, AB, Some might be COM, NC, NO. I will just reference the A, B, AB markings, but the other markings would be the same.

If you have a simple install A to port tank, B to Starboard tank, and AB to the engine there are still several ways that the valves may work depending on the spec for the specific valve. Some possible configurations:

As you move from A to B, some valves will completely shut off the A, before the B starts flowing. if you center the valve, you get nothing.

Some others will flow 50/50 if you hit dead center, pulling equally from A and B.

Other valves when the handle is dead center and you expect 50/50 will actually flow twice the flow through the A port as they will through the B port. (other ratios are also available although I know of no valves that would flow more through the B port than the A port).

I bring this up in case you are experiencing unexpected results, it could be that the valve is not really the correct valve for what you are expecting. Also, it is not uncommon for 3 way valves to be mounted in a convenient way based upon the direction the ports are pointing, and not how they are intended to be plumbed.

 

[paulga]

i changed all 3 racor primary filters tonight. somehow i was not able to position the vacuum gauge facing forward like they were before, is there any good method to do that?



The two engine racor filters seemed successful, but the Gen racor filter is a problem.

it is different from the engine racors:

- the pressure gauge has only one black needle, no red needle.
- The pressure gauge has no T handle.
- its drain setting tightens clockwise (viewing from above), while the engine racors drains valve tightens counterclockwise (viewing from above)
- after I removed the gauge, it drained affluently even with the drain setting already tightened (engine racors do not drain when the valve is tightened)



the gen racor filter looked dirty and has stayed a long time. I put in a new filter in but now I have no method to add fuel into the gen racor. After I opened the pet cock of both fuel tanks and the control valve to the gen racor, the fuel does not flow inside the bowl. actually it is dripping slowly. i think the bowl does not seem to hold any fuel now. I tested adding a small amount of fuel into the bowl before tightening the lid, but it just drained from the bottom.

what could have gone wrong?

 

[twistedtree]

If you pour fuel into the filter chamber and it comes out the drain on the bottom of the bowl, then the drain isn't closed. Is that what you are saying is happening?


I have never encountered a racor drain that closes counterclockwise. Always clockwise per normal thread rotation. BTW, the whole clockwise, counterclockwise things is always relative to facing the screw or device. So in the case of your filters, it's facing the bottom of the bowl.


I think you would benefit from some introductory books on plumbing, home maintenance, basic electrics, etc. Read them all cover to cover. Nigel Calder has a bunch of books, along with other people. I applaud your willingness to take this on and to learn, but you really are starting at ground zero.

 

[Bmarler]

If it’s draining out the bottom you don’t have the drain closed, or, There’s something going on with at drain, and you just need to figure it out. Try screwing it fully the other direction and see if it closes. If not, you may have a bad o-ring on it.

 

[paulga]

maybe i got confused about the direction of valve when I was working on the third racor. will double check later.

when you loosen the drain fitting, the valve moves downwards, tightening moves it upward. correct?

If you pour fuel into the filter chamber and it comes out the drain on the bottom of the bowl, then the drain isn't closed. Is that what you are saying is happening?


I have never encountered a racor drain that closes counterclockwise. Always clockwise per normal thread rotation. BTW, the whole clockwise, counterclockwise things is always relative to facing the screw or device. So in the case of your filters, it's facing the bottom of the bowl.


I think you would benefit from some introductory books on plumbing, home maintenance, basic electrics, etc. Read them all cover to cover. Nigel Calder has a bunch of books, along with other people. I applaud your willingness to take this on and to learn, but you really are starting at ground zero.

 

[paulga]

If it’s draining out the bottom you don’t have the drain closed, or, There’s something going on with at drain, and you just need to figure it out. Try screwing it fully the other direction and see if it closes. If not, you may have a bad o-ring on it.

are you saying the draining fitting has an o-ring?

i saw this small o-ring came out together with the lid and gauge. It's smaller than the gauge bolt dia and looked worn out. I couldn't figure out where it was from.

i didn't see the same small o-ring when i replaced the engine racor fitlers.

 

[Bmarler]

Drain valves can seem backwards at times, depending on what type you have. Moving up may open the passage for draining.

 

[Bmarler]

are you saying the draining fitting has an o-ring?

i saw this small o-ring came out together with the lid and gauge. It's smaller than the gauge bolt dia and looked worn out. I couldn't figure out where it was from.

i didn't see the same small o-ring when i replaced the engine racor fitlers.

View attachment 144039

Yes, the drain has an o ring. I can’t say if the one you have is the one from the drain, but it’s possible. A completely missing o ring would certainly cause the drain to leak continuously.

 

[twistedtree]

when you loosen the drain fitting, the valve moves downwards, tightening moves it upward. correct?

Not necessarily. Clockwise should close it, and counterclockwise should open it.

 

[TJM]

If memory serves me correct, there is supposed to be an O-ring (as you show on the wire) under the Racor top lid. This seals the lid around the threaded stud that tightens the lid.
Every time you perform a filter change, you should replace the small O ring and the flat gasket around the outside of the lid. They are supplied with a new pleated filter. I keep the old O rings and gaskets just in case. Go on the Racor site to see how the fuel flow is, it may answer some of your questions. The bowl does not need to be completely full of diesel to work properly.

 

[Cartouche]

If memory serves me correct, there is supposed to be an O-ring (as you show on the wire) under the Racor top lid. This seals the lid around the threaded stud that tightens the lid.
Every time you perform a filter change, you should replace the small O ring and the flat gasket around the outside of the lid. They are supplied with a new pleated filter. I keep the old O rings and gaskets just in case. Go on the Racor site to see how the fuel flow is, it may answer some of your questions. The bowl does not need to be completely full of diesel to work properly.

There is and it needs to be changed along with the main gasket comes with the kit

 

[paulga]

If memory serves me correct, there is supposed to be an O-ring (as you show on the wire) under the Racor top lid. This seals the lid around the threaded stud that tightens the lid.
Every time you perform a filter change, you should replace the small O ring and the flat gasket around the outside of the lid. They are supplied with a new pleated filter. I keep the old O rings and gaskets just in case. Go on the Racor site to see how the fuel flow is, it may answer some of your questions. The bowl does not need to be completely full of diesel to work properly.

the racor filter package has 1 square cross-section gasket (black) and 1 small o-ring (red). the seal goes to the lid and the o-ring goes up the T handle rod (in the case of my gen racor, there is no T handle, only a gauge threaded into a hex nut).

the mysterious o-ring (black) is even smaller than the red o-ring, it somehow came out with the gauge rod and separated from the bottom of gauge rod when I laid the gauge on the oil pad.

not sure if the racor will function without this small o-ring

all 3 racors are 500FG. the difference of the third one might be in the T handle thing.

I'll check the drain fittings.

 

[twistedtree]

The racor manual can be found online and includes a parts diagram showing all the parts and how they fit together.


Another possibility is that the little o-ring is not from the filter assembly, but is debris that got trapped by the filter. But I would check the parts diagram first to see if it's part of the filter assembly.

 

[paulga]

Thanks for all your inputs
I was able to close the drain fitting of the gen racor and top up using a disposable cup.

I also took the time to change the secondary filters. I paid for a mechanic to do it in October, his method of pre filling the filter and bowl before bolting it in has proved useful.

To prime the two spin on filters plus one racor filter consumed half gallon fresh diesel.