Duel fuel filter installation!

[seafox67]

After suffering last year with diesel bug, one of my winter projects is to install my homemade duel filter system!

I am also planning to fit an inline bulb pump to aid priming....

Should I install the priming pump before the duel filters or after? Or, does it not really matter!

Cheers
Paul

 

[Caer Urfa]

The bulb should be fitted after the filters to draw fuel into them when empty , I fitted duel filters (one for each tank) each running from its own tank down to a three way changeover valve, that way I could select port or starboard tank or midway setting from both,
At sea I did have a blockage once and simply switched over the valve to the other tank and sorted out the blockage when I got back.
Also recommend to fit some simple butterfly type shut off valves one below each tank but before the filter, plus one before the bulb pump, also two on the fuel return system to divert return fuel to its own tank

 

[seafox67]

The bulb should be fitted after the filters to draw fuel into them when empty , I fitted duel filters (one for each tank) each running from its own tank down to a three way changeover valve, that way I could select port or starboard tank or midway setting from both,
At sea I did have a blockage once and simply switched over the valve to the other tank and sorted out the blockage when I got back.
Also recommend to fit some simple butterfly type shut off valves one below each tank but before the filter, plus one before the bulb pump, also two on the fuel return system to divert return fuel to its own tank
View attachment 102360View attachment 102361View attachment 102361View attachment 102362View attachment 102362View attachment 102363

That looks very impressive! I've just got the one fuel tank but last year the bug stopped my engine whilst going through some narrows. It got a little scary being single handed so i'm hoping with this duel filter system I can quickly switch over to a clean filter and get to an anchorage where I can sort things out!

 

[prv]

You need somewhere for the air that was in the newly-fitted filter to be pushed out of the system, and it needs to be after the pump otherwise it will be an air entry point rather than an exit point. Conventionally that’s the filter bleed screw, which means the pump has to be before the filter. However, if you have a convenient bleed point further along the pipe, or if the low pressure side of your engine allows air to be pushed right through and back down the return pipe, you could put the pump after the filter. In theory this avoids the risk of debris blocking the pump, though if you have big enough chunks of crud in the tank that they could block a typical rubber bulb pump, they’ll probably also block the dip tube sooner or later...

Pete

 

[seafox67]

You need somewhere for the air that was in the newly-fitted filter to be pushed out of the system, and it needs to be after the pump otherwise it will be an air entry point rather than an exit point. Conventionally that’s the filter bleed screw, which means the pump has to be before the filter. However, if you have a convenient bleed point further along the pipe, or if the low pressure side of your engine allows air to be pushed right through and back down the return pipe, you could put the pump after the filter. In theory this avoids the risk of debris blocking the pump, though if you have big enough chunks of crud in the tank that they could block a typical rubber bulb pump, they’ll probably also block the dip tube sooner or later...

Pete

I've got a Volvo D1-20 which has a bleed screw on the engine fuel filter. Just thinking about possible large bits of debris... maybe if I put the pump before the filters I could then have the option to disconnect the pipe from the filters and use the pump to drain out any of the bug gunk!

 

[scottie]

Impressive but why stick with 296 elements and not use spin on

 

[seafox67]

Impressive but why stick with 296 elements and not use spin on

Cos they were cheap! lol... and the replacement filters are so easy to get around the world!

I know they are a pain to change but having lived with the bug issue for most of the season I can now swap a filter out in less than 5 minutes! lol.

 

[prv]

I've got a Volvo D1-20 which has a bleed screw on the engine fuel filter.

May be even easier, if you’re lucky. With my D1-30 I can pump air and fuel right through the system and back to the tank, so I don’t need to do any messy bleeding at all. I just fit the new filter, and start pumping. First the clear filter bowl fills up, then there’s a pause as the filter itself fills and the displaced air makes its way through the engine, then I start hearing bubbles in the tank as the air from the filter comes through the return pipe. When the bubbling stops I know the whole loop is full of fuel and clear of air, and I can stop pumping. Only takes a few seconds.

I don’t know for sure but it seems likely that the D1-20 would work similarly. Of course you’d need a dip pipe on the return to hear bubbling, but you might perhaps be able to tell by splashing instead if your return just empties into the top?

Pete

 

[seafox67]

May be even easier, if you’re lucky. With my D1-30 I can pump air and fuel right through the system and back to the tank, so I don’t need to do any messy bleeding at all. I just fit the new filter, and start pumping. First the clear filter bowl fills up, then there’s a pause as the filter itself fills and the displaced air makes its way through the engine, then I start hearing bubbles in the tank as the air from the filter comes through the return pipe. When the bubbling stops I know the whole loop is full of fuel and clear of air, and I can stop pumping. Only takes a few seconds.

I don’t know for sure but it seems likely that the D1-20 would work similarly. Of course you’d need a dip pipe on the return to hear bubbling, but you might perhaps be able to tell by splashing instead if your return just empties into the top?

Pete

That would be brilliant if I didn't need to bleed the system! Although the D1-20 does have a bleed screw so I'm guessing it is there because you can't push the air through the engine. However, there is a return fuel hose that goes from around the injectors back to the top of the fuel tank! I'll need to investigate more... cheers

 

[alan_d]

The bulb should be fitted after the filters to draw fuel into them when empty

You may be right, but why? Why not before the filter(s) to fill them with fuel?

 

[neil1967]

Apparently when fuel goes through a low pressure pump it gets mixes it up and compressed which makes it less likely that the subsequent filter will remove any water in the fuel - or so the theory goes.

 

[gregcope]

@seafox67 nice setup.

where did you get the parts? Esp those three way valves?

 

[Stemar]

When I did the same thing, for the same reason a few years ago, I went to a car breaker and got a matching pair of fuel filters with spin-on cartridges, because I hate CAV O rings with a passion. Valves came from ASAP, but I used two pairs of simple on-off valves because that was a good bit cheaper than three-way jobs. The whole job cost me about £50.

I didn't need a primer pump because the fuel tank is above the filters. I've never needed to, but in theory, I could change and bleed one filter while the engine's running on the other one.

 

[seafox67]

@seafox67 nice setup.

where did you get the parts? Esp those three way valves?

I got the filters off ebay... under £20 each and valves are three-way 1/4" which were about £30 each. One valve controls the input and the other, the output so to switch over the filter you turn both valves in the same direction.

 

[Rappey]

A friend got caught in a race and was motorsailing through it. The engine died.
He had 4 spare filters on board.
In no time at all he got through all his filters and ended up with a tow from a passing fishing boat.
The sea state churned up his fuel tank and a large amount of black slime was dislodged which no amount of filtering would temporary fix.
We concluded it would be good to have a day tank , filled through its own filtration system and a valve to turn off the main system and turn on the day tank .

 

[seafox67]

A friend got caught in a race and was motorsailing through it. The engine died.
He had 4 spare filters on board.
In no time at all he got through all his filters and ended up with a tow from a passing fishing boat.
The sea state churned up his fuel tank and a large amount of black slime was dislodged which no amount of filtering would temporary fix.
We concluded it would be good to have a day tank , filled through its own filtration system and a valve to turn off the main system and turn on the day tank .

Sounds like a good idea... My engine died at the narrows in Kyles of Bute. However, I was lucky that the new filter lasted a good 20 miles to get me back home.

The filters that I'm using was part of a fuel polishing system I built however with the amount of the black stuff in the tank the polishing system was getting blocked within just a few minutes of operating!
So, I bought a 2nd hand wet vac and made an inspection hole in the tank which allowed me to hoover up the bottom of the tank (I will do this every year now)!
I am also thinking about having a method of using a clean 20l tank, using the bulb pump to prime it!

I never thought that I would have ever got diesel bug (in Scotland) with all the fuel treatments I use but getting caught out so close to rocks in a strong current has definitely encouraged me to have more that one plan!

 

[Tamar]

A friend got caught in a race and was motorsailing through it. The engine died.
He had 4 spare filters on board.
In no time at all he got through all his filters and ended up with a tow from a passing fishing boat.
The sea state churned up his fuel tank and a large amount of black slime was dislodged which no amount of filtering would temporary fix.
We concluded it would be good to have a day tank , filled through its own filtration system and a valve to turn off the main system and turn on the day tank .

A Jerry can filled with clean diesel and a short pipe to the fuel pump will get you home

 

[TernVI]

A friend got caught in a race and was motorsailing through it. The engine died.
He had 4 spare filters on board.
In no time at all he got through all his filters and ended up with a tow from a passing fishing boat.
The sea state churned up his fuel tank and a large amount of black slime was dislodged which no amount of filtering would temporary fix.
We concluded it would be good to have a day tank , filled through its own filtration system and a valve to turn off the main system and turn on the day tank .

Day tank works well for a lot of people, with bigger tanks etc.
The alternative is to know there's never enough crud in your tank to choke the filter. I think that's a good way with small tanks and low annual diesel use.
I have seen a few yachts with bug problems, and if there's enough crud to block one filter, there's always been enough to block several.

 

[Rappey]

Jerry can filled with clean diesel and a short pipe to the fuel pump will get you home

My problem with that would be bleeding the system which can take up to an hr with multiple attempts.
The idea of a day tank was that it is already connected and good to go.

 

[[70521]]

A Jerry can filled with clean diesel and a short pipe to the fuel pump will get you home

And don't forget to sort out the return!