CAV filter issue

Laysula

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I have had CAV filters on all my yachts since 1993. Never had a problem with them, Two years ago I got diesel bug and so cleared everything out, I also replaced the CAV with a Racor 500 type as people kept saying how good they were.

I was amazed at how much cleaner and easier it has now become to change a filter.
Just dump the CAV and replace it with a Racor 500 type. less than £20 on ebay. You won't regret it.
 

srm

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I have never changed one at sea, how is it different please?
Blocked filters usually occur in lively conditions that shake the contents of a fuel tank and stir up any sediment that may have settled in the bottom. Not many people enjoy working in a confined space with smelly diesel while the boat is bouncing around. It makes a potentially messy job very difficult.
 

Graham376

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Blocked filters usually occur in lively conditions that shake the contents of a fuel tank and stir up any sediment that may have settled in the bottom. Not many people enjoy working in a confined space with smelly diesel while the boat is bouncing around. It makes a potentially messy job very difficult.

Having had to change a CAV in lively conditions on a previous boat, I no longer use them. Have Baldwin spin-on on current boat with separate glass bowl sediment/water filter before it.
 

iamtjc

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I struggled with changing my CAV filter, getting the seals to sit right etc. It all became very much easier once I realised I could unbolt the entire filter from the bulkhead in the bilge and lift it up a few inches where I could actually see what I was doing. You will need a little slack in the pipework to do this, but I had and it really helped.
 

Freebee

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since nobody answered the OP question in the photographs are 2 different forms of the 296 element both are equally useable but one has about 10 times the dirt holding capacity of the other. The one with holes in the top has just one pleat but its rolled up like a toilet roll and sealed together top and bottom it has a massive surface area. the other is just vertically pleated, given the choice I would take the one with holes in the top every time ALTHOUGH I would really go with a small Facor which is far more user friendly.
 

Jon magowan

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I struggle changing my CAV filter element as well. Because of where it’s positioned. Very awkward.

As a newbie I would love to understand if the Racor type of filter is much better than the CAV? I’m guessing it must be, because they are extremely expensive. Are they really so much better ?

I presume when people refer to the ‘Facor’ this is actually a fake Racor. Do these copies work just as well as the real thing ?
 

rogerthebodger

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Having been involved in servicing cars before spin on oil filters I learned haw to get the bowl seals fitted and the bowl located correctly in the seal groove.

The trick is to not tighten the filter too tight so the seal is damaged. The second is to just nip up the bolt and spin the filter until it beds down on the seal.

If you filter is in a difficult place to get at move it to a better place for easy servicing
 

snowbird30ds

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The facor is a racor copy and works the same, also takes genuine racor filters, they are much easier and cleaner to change filters.
When I fitted mine I bought 4 genuine racor filters as I doubt the cheapies have the aquabloc water repellent bit but I've not yet changed them so still have the cheapies in, so far no issues and my old tub does guzzle through diesel.
When I got mine swmbo spent a couple of weeks with a filter in her bag on the hunt for a handy container, b&m came up trumps with a microwaveable soup cup with sealing lid, I keep a spare in the cup and if needed changed in lumpy water the old one would go straight into the cup and sealed so it's not splattering diesel and can be sorted at a convenient time, I keep one beside each filter housing.
My housings are well above tank and engine level with no problems.
 

Daydream believer

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I had problems with my filter leaking for several years. My cousin. who worked on farm equipment said that I was a spanner monkey. That annoyed me as I have been working on diesel engines since my early teens.
I went to Does of Ulting with my calipers & measured several filters. Perkins, Donaldson, New Holland & Delphi. they all varied in diameter where the seals fitted.
My cousin pointed out that there are thousands of CAV filters in use throughout the world. He has changed them when up to his knees in mud & water in extreme conditions & never had any issues. It takes minutes.
He then asked if I had a clone. Mine had been installed by Hanse from new, so I naturally assumed it was the correct thing.
CAV is now Delphi. I bought a new one & hey presto. Never had a problem since. Even the hose connections were different. I now have long fuel hoses both sides & the filter mounted on studs with wing nuts. To change the filter I release the complete unit. Hold it over a bucket, Change it so all fuel goes in the bucket. Then re fit it in place. I pump the fuel through with a set of bellows, although my new engine now has a pump on the engine filter. I have not used that yet.
 

Stemar

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I struggle changing my CAV filter element as well. Because of where it’s positioned. Very awkward.

As a newbie I would love to understand if the Racor type of filter is much better than the CAV? I’m guessing it must be, because they are extremely expensive. Are they really so much better ?

I presume when people refer to the ‘Facor’ this is actually a fake Racor. Do these copies work just as well as the real thing ?
leaving aside the awkwardness of getting the seals to bed properly, they have two seals that are similar enough in size for it to be easy to mix them up, which guarantees a leak. In my experience, a spin-on cartridge type is far more foolproof.
 

Jon magowan

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Having been involved in servicing cars before spin on oil filters I learned haw to get the bowl seals fitted and the bowl located correctly in the seal groove.

The trick is to not tighten the filter too tight so the seal is damaged. The second is to just nip up the bolt and spin the filter until it beds down on the seal.

If you filter is in a difficult place to get at move it to a better place for easy servicing
Good tip. Thanks Roger !
 

Jon magowan

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leaving aside the awkwardness of getting the seals to bed properly, they have two seals that are similar enough in size for it to be easy to mix them up, which guarantees a leak. In my experience, a spin-on cartridge type is far more foolproof.
Thanks Stemar. I spotted that one !
A rubbish design really.
 

Noto

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I tried to change my filter, and have struggled with the seals in the past, as can never quite get a seal the right size for the top of the glass bowl, and keep re-using the old one, any ideas?
Anyway, not my main issue today, got it all put togther, and tried to refill, but after a short while the fuel started coming out the breather screw before fuel had got to the the glass bowl, whats the likely cause (got me stumped)?
Some additional info, on the removed old filter i did see some sludge suspect bug, see pic. And old filter has no holes on top surface, but new does, again see pics - any pointers here to my issue above?
I tried to change my filter, and have struggled with the seals in the past, as can never quite get a seal the right size for the top of the glass bowl, and keep re-using the old one, any ideas?
Anyway, not my main issue today, got it all put togther, and tried to refill, but after a short while the fuel started coming out the breather screw before fuel had got to the the glass bowl, whats the likely cause (got me stumped)?
Some additional info, on the removed old filter i did see some sludge suspect bug, see pic. And old filter has no holes on top surface, but new does, again see pics - any pointers here to my issue above?
Depending on the section , could be circular or square , these are available to by cheaply 10mts £15. And using a safety razor blade to cut the Nitrile rubber and super glue together.
I have a Loctite "O" ring kit (to make your own ) on my boat just for emergencies. But other replies would be a permanent solution.
 
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