fuel lines

T

tangerine

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hampshire uk
www.normanwhite.co.uk
My colvic sunquest 29 "LennyVee" is equiped with 2 x Volvo AD31 diesels. There is no water trap between tank and engines, just one canister filter per engine attached to a bulkhead,and the same type filter attached to engines. Although Ive experienced no problems in the 4 years Ive owned her,im sure I should have a water traps/glass bowls with taps. Does anyone know where I can find a pair,other than Volvo,who Im sure would be very expensive?
 
tangerine said:
My colvic sunquest 29 "LennyVee" is equiped with 2 x Volvo AD31 diesels. There is no water trap between tank and engines, just one canister filter per engine attached to a bulkhead,and the same type filter attached to engines. Although Ive experienced no problems in the 4 years Ive owned her,im sure I should have a water traps/glass bowls with taps. Does anyone know where I can find a pair,other than Volvo,who Im sure would be very expensive?
Click to expand...

Experience leads me to have very different views on marine fuel filteration.

Looks like the person who installed your engines was clueless. Your on engine filters are your 'last chance filters'. You require at least another line of defence, in reality two.

Please please forget old style CAV filter heads, they are from another era and are as much use to you as a rubber eye. Vey little in the way of coalescing properties, very poor Beta ratio, messy to change, bowls go yellow so impossible to see through, completely pointless. On the upside they cost next to nothing, however give little back in return.

Just a few pointers as the installer of your engines cannot be relied upon to have followed a few simple rules.

1) It's always best to either draw your fuel from the bottom of the tank (you want the **** in your filters and not sitting in the bottom waiting to get stirred up in the first bad weather), OR have a drainable fuel tank sump, OR BOTH.

2) Be sure the fuel lines, valves and fittings that feed your filters do not restrict the flow or allow air to enter the system. Choosing the next size of filter in capacity ratings will assure you of a longer time between clogging.

3) A vacuum gage installed just before a fuel lift pump will more that pay for itself if installed correctly and its operation is understood by the operator. The use of a vacuum gage adds "science" as to when to change your filters.

5) Always be sure the filters you choose to use are sized in stages with the largest capacity and nominal micron rating closer to the fuel tank.

6) Be sure your return fuel system cannot be shut off when switching tanks or at any time during engine operation.

7) Make sure your system has a submerged return line, original installer appears nor to have read the Volvo installation manual.

Before poster suffering from 'Racoritis' chime in, this 40 plus year old design has its place however as many boaters will confirm servicing a Racor can be a challenge if you want to try and keep the bowl clear and clean. Lots of parts, seals and just a plain hassle and extremely messy to deal with. If you want to keep it clean you will have to install a bulk separator in front of it. More times than not, I have seen the bowl on a Racor so dirty that its effective use as a "visual" has become totally worthless, just like the CAV. I prefer not to rely on a visual check of nasty yellow bowl at all, but to simply drain a sample of fuel from filter before you use your vessel.

My vote is always for simple to change spin on filters with decent coalscing properties.

As a MINIMUM of protection a spin on FF105 will provide you with your fist line of defence. Easy peasy to change when life goes pear shaped, and far less expensive than a Racor and more effective. People here have mentioned on line filter providers who sell filters and heads for peanunts.
 
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Latestarter1 said:
Experience leads me to have very different views on marine fuel filteration.

Looks like the person who installed your engines was clueless. Your on engine filters are your 'last chance filters'. You require at least another line of defence, in reality two.

Please please forget old style CAV filter heads, they are from another era and are as much use to you as a rubber eye. Vey little in the way of coalescing properties, very poor Beta ratio, messy to change, bowls go yellow so impossible to see through, completely pointless. On the upside they cost next to nothing, however give little back in return.

Just a few pointers as the installer of your engines cannot be relied upon to have followed a few simple rules.

1) It's always best to either draw your fuel from the bottom of the tank (you want the **** in your filters and not sitting in the bottom waiting to get stirred up in the first bad weather), OR have a drainable fuel tank sump, OR BOTH.

2) Be sure the fuel lines, valves and fittings that feed your filters do not restrict the flow or allow air to enter the system. Choosing the next size of filter in capacity ratings will assure you of a longer time between clogging.

3) A vacuum gage installed just before a fuel lift pump will more that pay for itself if installed correctly and its operation is understood by the operator. The use of a vacuum gage adds "science" as to when to change your filters.

5) Always be sure the filters you choose to use are sized in stages with the largest capacity and nominal micron rating closer to the fuel tank.

6) Be sure your return fuel system cannot be shut off when switching tanks or at any time during engine operation.

7) Make sure your system has a submerged return line, original installer appears nor to have read the Volvo installation manual.

Before poster suffering from 'Racoritis' chime in, this 40 plus year old design has its place however as many boaters will confirm servicing a Racor can be a challenge if you want to try and keep the bowl clear and clean. Lots of parts, seals and just a plain hassle and extremely messy to deal with. If you want to keep it clean you will have to install a bulk separator in front of it. More times than not, I have seen the bowl on a Racor so dirty that its effective use as a "visual" has become totally worthless, just like the CAV. I prefer not to rely on a visual check of nasty yellow bowl at all, but to simply drain a sample of fuel from filter before you use your vessel.

My vote is always for simple to change spin on filters with decent coalscing properties.

As a MINIMUM of protection a spin on FF105 will provide you with your fist line of defence. Easy peasy to change when life goes pear shaped, and far less expensive than a Racor and more effective. People here have mentioned on line filter providers who sell filters and heads for peanunts.
Click to expand...

Thanks for your input Latestarter 1,. Most of your points I have in place except for a vacum guage. I assume FF105 is a primary filter. Is this a Volvo part? If not, where do I find more info/purchase ? Does FF105 have water drain tap?
 
Ff105 or it's equivalent in Baldwin is a perfect cheapish filter for your engine I fit hundreds every year, though not sure where to buy the head from that the filter screws to , you could try nick at sea bridge marine as sealine fit them to there smaller boats. On the other hand a racor with a 2010 element in is a good bet as the elements in 30 micron are around £10 about the same as the fleet guard ff105c.
 
CAV do a head that will allow a spin on filter with a drain off point at the bottom to remove or check for water.

I agree with most of what Latestarter says about Racor filters with the proviso that they are very good on larger engines and you can move a lever to use a new filter if indeed one gets blocked.

This is what I use on Little Ship both for my engine prefilter and my small fuel polishing system, it seems to answer all the questions raised. It filters down to 5-7 microns

http://www.thornycroftparts.co.uk/F...tor_Diesel___Petrol_Boat/p207754_422946.aspx#

Tom
 
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LittleShip said:
CAV do a head that will alow a spin on filter with a drain off point at the bottom to remove or check for water.

I agree with most of what Latestarter says about Racor filters with the proviso that they are very good on larger engines and you can move a lever to use a new filter if indeed one gets blocked.

This is what I use on Little Ship both for my engine prefilter and my small fuel polishing system, it seems to answer all the questions raised. It filters down to 5-7 microns

http://www.thornycroftparts.co.uk/F...tor_Diesel___Petrol_Boat/p207754_422946.aspx#

Tom
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Tom,

This is where I appear to swim against the tide.

Most manufacturers have a MINIMUM primary fuel filter requirement along the lines of:

Minimum 10 microns, separator must have a 36 gram minimum capacity per SAE J1905.
Filter must remove 95% (or more) coarse water droplets over the life of the filter, per SAE1488. Now ask yourself, do I really want to meet minimum requirements??

Cannot find any technical stuff on the CAV Delphi filter listed, however when I cross reference it with Baldwin the technical spec falls way way short of the above minimum requirement. It appears to be way too fine and lacking capacity to do the job as a primary.

In my earlier posting see notes 2 and 5. We need a 'rock, gunk, crud' stopper as first line of defence. Once in a lively seaway the porrige in bottom of the tank becomes stirred up, we need a filter which removes majority of this junk without becoming too restricted. My rule on first line of defence is generally 20 mic beta rating filter, a flow rate of 100 GPH clean, with ½" Hg pressure drop. My ideal is then a second stage filter of say 10 micron, leaving the 'last chance' 5 micron (common rail 2 micron) on engine filter an easy life.

I still get sea sick and smell of Diesel does not help at all, no desire to mess with filters at sea.

The double Racors were never designed to switch over in the event of blockage, the concept was all about servicing constant running engines (generators) without taking set off line. I can make Racors work properly and keep the yukky bowls clean, however it requires a 'rock,crud' stopper in front then use Racor as second stage.

Paul
 
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Paul, I agree with all you say here....

All I will say is that my system works and works well, I have clean fuel (now) and I can check if I have water in the filters.

Like me, most of the guys on here are running very frugal engines and need to keep there limited fuel supply as clean as they can.

I will say that if my tanks were contaminated I would be looking for a pre-filter that would only remove large contaminates (20microns + instead of 5-7) but and it is a large but, I am trying to keep all contaminates out of my fuel supply which is what I think the OP is trying to do.

Regular checking for water ingress at the filter and regular changing of the filter I posted, would accomplish that for the OP without spending a fortune on some technical wizardry like a racor setup.

A vacuum gauge is another saftey item with this type of setup as it will let you know when the filter is becoming blocked.

It's the way it looks from here, we all have our views, this is mine.

Tom
 
I would have to agree with Latesterter on this one as we have similar issues with our dedicated industrial power packs which are often shipped around the world, and primarily suffer when first installed and run after shipping.

We fit well above the minimum filtration requirements, and use three stages of filtration as transportation agitates the debris from the bottom of the tanks and clogs the filters, which used to be a common problem. Due to our specific working requirements, we fitted bottom fed return lines and excessive filtration with spin off cartridges, and fuel tank filtered breathers, this has not stopped the issues, but they are negliagable.
 
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