Can I take a fuel connection from the water seperator?

icarusbop

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Hello:

The boat I am buying has a Volvo Penta D2-55 I have not taken ownership yet but an trying to be as prepared as possible.
The engine is fed via the Volvo fuel/water separator with the aluminium bottom.
On the separator there are four junction points, two have arrows pointing in. two have arrows pointing out.
Two are un use (in /out) for the engine two are blocked off with a threaded plug.

Can I use the Out arrow currently blocked off to feed an Eberspacher cabin heater? If so, what size threaded unit will I need?

Thanks

IcarusBop
 
It is not recommended to do that, the reason for the double in/out is to give installation flexibility.

There is a possibility that you get air into the fuel supply to the engine.

The best way to do this is installing a dedicated fuel pick up tube
 
my understanding is that there are issues with putting 2 units on the same feed where each unit will be subject to competition with the other. There is a risk that, for example, the engine overpowers the heating fuel pump and sucks air. It is very simple to fit a dedicated supply for the eberspacher and many fuel tanks have a spare port on the cover for this.
 
The best way to do this is installing a dedicated fuel pick up tube

It is very simple to fit a dedicated supply for the eberspacher and many fuel tanks have a spare port on the cover for this.

Thanks for the feedback - I was hoping to not interfere with the fuel tank and lines, but never mind.
I've had a look at the tank photos I have, there is no extra pick-up from what I can see.
There is a pick-up elbow connected to a (presumably) rubber hose, and similar for the returned fuel.

Is it best to drill the tank and install a new pick-up or could I break in to the current feed with a T-connector?
The issue then is the fuel to the cabin heater will not be filtered, does an Eberspacher care about this? Or should I then fit a filter unit, but would that increase the draw pressure required?

Regards:
IcarusBop
 
The above replies are technically correct, however we have the same D2-55 engines with Racor water separator/filter unit with two in and out ports. I plumbed our Mikuni heater fuel supply into the unused out port on the Racor many years ago and have never had the slightest problem with air getting into the system.
Modern diesel engines are much more tolerant of air in the fuel supply lines (although it is best avoided) than older engines - I can normally change the Racor filter element and then start the engine without bleeding the system, it will splutter a bit as the air is purged but invariably it will self bleed without too much of a problem.

Also you can consider how often you are likely to need to run the engine and the heater at the same time - we always seem to use one or the other, hardly ever both together so the problems mentioned above are largely irrelevant. If it avoids having to drill and fit another take off pipe into the fuel tank then I would certainly give it a go. I think you will find most fuel filter ports will be 1/4" BSP but if you contact ASAP Supplies and describe your filter they will almost certainly know what thread size you need.
 
Thanks for the feedback - I was hoping to not interfere with the fuel tank and lines, but never mind.
I've had a look at the tank photos I have, there is no extra pick-up from what I can see.
There is a pick-up elbow connected to a (presumably) rubber hose, and similar for the returned fuel.

Is it best to drill the tank and install a new pick-up or could I break in to the current feed with a T-connector?
The issue then is the fuel to the cabin heater will not be filtered, does an Eberspacher care about this? Or should I then fit a filter unit, but would that increase the draw pressure required?

Regards:
IcarusBop
A T connector would give same problem, the engine can draw air from the line to the Eberspacher
We have a small inline filter on the fuel line to the Eberspacher.
from the manual https://www.maritim.no/content/mma/publish/06/637/63757/airtronic_d2-4-5_marine_heater_22278.pdf

The fuel system supplied comprises of a fuel standpipe,a quantity of fuel line, shut-off valve, connectors and afuel-metering pump.

The diagram illustrates a typical installation using a fuelstandpipe, which is the preferred method for the fueltake off. This minimises any problems caused by overpressuring, fuel starvation and air leaks that can occur ifconnected to an engine fuel line.

However, fuel can be taken from an engine fuel lineif it is approved by Eberspächer, and the engine/boatmanufacturer (See technical description manual).
Unapproved connection may affect the terms of yourwarranties.Installing the standpipeThe fuel standpipe supplied must only be fitted to the topof the fuel tank and on an even surface. It must not befitted to the side or bottom of the tank.
 
If you speak to your local diesel pump, injector specialist, non return valves that screw directly into the filter head are available for a few quid. 1/2" x 20 unf on cav, delphi etc.
 
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I'm another who has fitted a Webasto heater to the 2nd Out on a Racor water separator/filter. The engine is a Volvo 2003. Like crisjones, we never experienced a problem with air getting in anywhere.

I suppose the possibility exists of drawing air into the engine fuel pipe if a fault were to develop in the heater fuel system but, in at least 10 years of use, there's not been any sign of that.

Like crisjones, our usage pattern is to be either motoring or sitting moored with the heater on, almost never using angine and heater simultaneously. But I think the pipework and racor filter are comfortably oversized to accommodate both loads without demur.

Derek
 
My Eberspacher draws fuel from a T downstream of the primary filter. It has been like this for years and has worked faultlessly. After I posted pictures of it on my website I was contacted by Eberspacher. These are the comments,:

I have received the following from Mr Peter Collard, Technical Engineering Manager of Eberspacher UK.
I appreciate that your tee into your fuel line has not caused you any problems but there are several different reasons why we specify this:
A, It is contrary to Recreational Craft Directive (RCD) ISO10088. Although this is written specifically for engines it is generally accepted in the industry that all fuel systems must abide by this standard. (this can lead to big issues if an insurance claim is required)
B, if a fuel line is not under positive pressure, as most boats are not these days, it affects the fuelling of the heater because the pump is not designed to pull up a large bore engine fuel line or stand pipe.
C, If there is a minor fuel leak on the engine system at any point, or the pump, injector etc. is not sealing, the heater, if run without the engine, can pull air into the engine fuel line.
D, plastic parts are not permitted in the fuel system these days again by both RCD and if you are in an estuary Boat Safety Scheme also applies.
 
Is it best to drill the tank and install a new pick-up or could I break in to the current feed with a T-connector?
The issue then is the fuel to the cabin heater will not be filtered, does an Eberspacher care about this? Or should I then fit a filter unit, but would that increase the draw pressure required?

Regards:
IcarusBop

It's better to drill the tank, and install a dedicated pickup for your heater. I did this a few years ago, on our old boat and it was quite straightforward. I also fitted a small in line disposable filter, available for a couple of quid from any motor factor. This worked fine for the duration of our ownership, and I assume is still going strong. Interestingly, on our new boat the professionally fitted heater had exactly the same set up.
 
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