CAV Fuel Filters

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Babylon

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I have a traditional metal-bodied CAV fuel filter which takes the Delphi 296 filter, and which has a plastic screw-in drain plug on the bottom. A couple of questions or so:

Are these units 'handed' - ie can I move it from the port side of the engine bay to the stbd side?

If I do move it to the stbd side (that's where the fuel intake is located on the new Beta engine) and have to replace it with the correctly-handed one, can I fit a version with a glass bowl so I can see if there's any water in the fuel? The one I'm looking at is http://www.dieselpartsdirect.co.uk/...on/Agglomerators/5836B325-Delphi-Agglomerator however this seems to have a much shallower glass bowl compared to the all-metal one.

Is the glass bowl safe?

Finally, the 296 replacement filter comes with two large circular seals (obvious where these fit) and a very small circular seal (not obvious where this goes). What's the small one for?

Thanks
 
there's a view that glass bowls are liable to crack and dump fuel. I had a BSS inspector who was very set against them.

Fuel filter bowls can be affected by the heat from an engine and from impact damage,and failure of a bowl could result in additional fuel being added to any fire. Some bowls are specially designed for fire and impact resistance in the marine environmentuse. Some bowls are designed for diesel and some for petrol only. There's an ISO standard - 10088 .

That said, we have glass fuel filter bowls on the tractors, and they live very hard and bumpy life. No problems, so far.
 
No they're not handed. However there are usually arrows cast into the header to indicate which are the inlet and outlet ports.

As for a glass bowl - the spindle from the base needs to be the right length as there are a few different types. Have a look on here to get an idea of the different types:
http://www.asap-supplies.com/brands/cav-type#top

I've had glass bowls on a couple of boats with no safety problems; the glass is quite thick but obviously careful siting and only tightening it sufficiently to stop any leaks will help to avoid any accidents.

The really small O-Ring goes on the centre spindle in the header.
 
Following earlier contaminated fuel problems, bought a CAV replacement for my exisiting agglomerator a few weeks back & as I already had a see-through bowl, essentially got the same but with the filter in addition. Rather as your link, but with a bigger bowl and less than half the price. It has an in & out port on either side with two blanking plugs, so you could position port or starboard. 1/2" or 14mm threads available.

Did look at spin on conversions and Racor alternatives, but much more expensive- £70-120 depending and more mucking about to fit. The CAV set looks to be a straight swap, tho yet to put in..

Link to supplier here:

http://www.ssldieselparts.co.uk/filter-assembly-sfa4-p-709.html

Delivery charges and times excellent, despite coming from North Uist!
 
sarabande said:
there's a view that glass bowls are liable to crack and dump fuel. I had a BSS inspector who was very set against them.

Fuel filter bowls can be affected by the heat from an engine and from impact damage,and failure of a bowl could result in additional fuel being added to any fire. Some bowls are specially designed for fire and impact resistance in the marine environmentuse. Some bowls are designed for diesel and some for petrol only. There's an ISO standard - 10088 .

That said, we have glass fuel filter bowls on the tractors, and they live very hard and bumpy life. No problems, so far.
Click to expand...

Will specifically fail the BSS. I had a metal bowl for inspection day only on my last 2 boats which had cav filters.
I'm told new racors are much better filters though and they are certainly easier to change the filters without making a mess.
 
Hi..
No help with the question about seals but I swapped out my old filter today and replaced it with a Racor unit from Hyphose in Portsmouth. Weird - I visited their store but they said it would be cheaper to buy online.. If you ask at the store you'll get online prices though.
Apparently the filter inserts are a little more expensive but it was so easy to screw the bowl to the filter, fill with fuel and then screw the whole lot up to the fitting. No tools needed at all. It was just like a standard oil filter!
If you have questions about the model numbers then just ask. Rgds Martin.
 
I have the CAV one and wouldn't buy another. Two problems:

1. A glass bowl broke on me, for no reason that I know of. We were anchored in very warm weather, inland Holland, and slept in the cockpit. In the morning there was a very strong smell of diesel and we found the engine bilge half full of diesel. We hadn't even run the engine the previous day, so no real reason for it to fail.

2. The seals can be very difficult to fit leak-free. I have struggled many times to get them to seat properly. Answering a question from above, the larger gasket goes between the filter and the base, the other goes between the filter and the bowl. Because the second one is a tapered seat it is tricky to get it right, especially if one is afraid of doing it up so tight that the bowl fractures.
 
vyv_cox said:
The seals can be very difficult to fit leak-free. I have struggled many times to get them to seat properly. Answering a question from above, the larger gasket goes between the filter and the base, the other goes between the filter and the bowl. Because the second one is a tapered seat it is tricky to get it right, especially if one is afraid of doing it up so tight that the bowl fractures.
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Couldn't agree more. ASAP Supplies (www.asap-supplies.com) do an assembly which converts a CAV head to accepting Racor-spin-on filters. These seal just as simply and effectively as a spin-on oil filter (especially useful if access to the filter assembly is at all awkward).
 
Can anyone lend any advice or experience why these CAV fuel filter/sediment bowls which have been in use on heavy road transport and earth moving equipment with little problems for 40+ years, suddenly become unreliable and a safety/maintenance issue in a yacht environment?
 
Just to add my experience - a glass bowl on a CAV shattered just as I pullled away from the slipway at launching, and a few months later a second one was found to have a cracked glass. The engineer said this was very rare.
 
macd said:
Couldn't agree more. ASAP Supplies (www.asap-supplies.com) do an assembly which converts a CAV head to accepting Racor-spin-on filters. These seal just as simply and effectively as a spin-on oil filter (especially useful if access to the filter assembly is at all awkward).
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There is an alternative, shown on the SSL site - their item SFA11 - a large, solid metal Delphi HD filter (5-7 um) which spins on (and has a water drain at the bottom), as fitted to a range of vehicles, including Land Rovers and the like, £20 for the whole unit, a fiver for a filter. Might I suggest a bargain when compared to Racor prices.
 
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I've used the CAV filters on plant equipment and boat for years and many changes without a problem. The problems are something to do with the skill level of operator I would say.
 
ksutton said:
Can anyone lend any advice or experience why these CAV fuel filter/sediment bowls which have been in use on heavy road transport and earth moving equipment with little problems for 40+ years, suddenly become unreliable and a safety/maintenance issue in a yacht environment?
Click to expand...

For most of its history the internal combustion engine got by without spin-on oil filters. Now they'e pretty well universal -- and thank heavens for that.

FWIW I'd say the same about V-belts, which are standard on pretty well no new car you can buy, but cling on grimly on marine engines.
 
ksutton said:
Can anyone lend any advice or experience why these CAV fuel filter/sediment bowls which have been in use on heavy road transport and earth moving equipment with little problems for 40+ years, suddenly become unreliable and a safety/maintenance issue in a yacht environment?
Click to expand...

I think the reason is:
Difficult to change without making a mess in the bilge. On a lorry it does not matter and more room for a container underneath.
 
macd said:
Couldn't agree more. ASAP Supplies (www.asap-supplies.com) do an assembly which converts a CAV head to accepting Racor-spin-on filters. These seal just as simply and effectively as a spin-on oil filter (especially useful if access to the filter assembly is at all awkward).
Click to expand...

Suffered same problems stopping leaks, apart from the mess of changing a filter.
I have removed and replaced with the Racor 500 series turbine filter. The filter on this can be changed in 1 minute, and makes no mess, and does not need bleeding. I my view a brain dead choice if you have the room.
 
ksutton said:
Can anyone lend any advice or experience why these CAV fuel filter/sediment bowls which have been in use on heavy road transport and earth moving equipment with little problems for 40+ years, suddenly become unreliable and a safety/maintenance issue in a yacht environment?
Click to expand...

Well in my case, I am trying to eliminate any leakage whatsoever to try to keep the interior of the boat from stinking of diesel. Most engines of heavy road transport and earth moving equipment that I see are candidates for hydrocarbons recovery plant with large puddles of fuel beneath them.

One incident with a CAV filter that will live forever in my memory was on a friend's boat that suffered from heavy diesel bug problems. It was midnight in Portpatrick harbour, in the lively conditions that result there from fresh southwesterly winds. We changed filters several times and finally had to resort to re-using ones whose seals had already swollen from contact with the fuel. I cursed the design and designer roundly, to little effect. It remained a lousy arrangement, and still is to this day.
 
vyv_cox said:
Well in my case, I am trying to eliminate any leakage whatsoever to try to keep the interior of the boat from stinking of diesel. Most engines of heavy road transport and earth moving equipment that I see are candidates for hydrocarbons recovery plant with large puddles of fuel beneath them.

One incident with a CAV filter that will live forever in my memory was on a friend's boat that suffered from heavy diesel bug problems. It was midnight in Portpatrick harbour, in the lively conditions that result there from fresh southwesterly winds. We changed filters several times and finally had to resort to re-using ones whose seals had already swollen from contact with the fuel. I cursed the design and designer roundly, to little effect. It remained a lousy arrangement, and still is to this day.
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There is a worse design, the CAV oil filter with the securing bolt entering through the bottom, try and get that off with out spilling oil, at least with the fuel version you can catch the spillage with a fizzy drink bottle
 
Jon, as Vyv has mentioned briefly, the two larger ring seals are of close but different diameters for the upper and lower halves. If I remember one of them has a blue mark to inducate the upper seal; putting the wrong one in sometimes means that through over-tightening to stem the seep of fuel, the glass can become cracked. I don't recall there being any problem with old seals whose removal has been forgotten, unlike the Oil filter seal rings where I've missed their removal in the past.

ianat182
 
ksutton said:
Can anyone lend any advice or experience why these CAV fuel filter/sediment bowls which have been in use on heavy road transport and earth moving equipment with little problems for 40+ years, suddenly become unreliable and a safety/maintenance issue in a yacht environment?
Click to expand...

I don't think anyone is saying they have suddenly become an issue. The BSS is keen to keep plastic and glass out of a potential hazad areas - I have no issue with that.

Perhaps they are are becomming an issue because some of them are 40+ years old and difficult to seal, prone to leaks and failure simply due to being 40+ years old????

I suspect a small bit of distortion and they would leak like a sieve, cheep enough to replace though and as stated above, an outstanding track record.
 
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