CAV 7111-690 Water Separator

[Aja]

My Moody has this water separator fitted but no primary filter.
View attachment 56562
I've done several searches based on the part number stamped on the casing 7111-690 but Google hasn't returned anything for the -690. I'd like to replace the separator with a filter and glass bowl the assembly sits outside of the engine compartment.

Question is I suppose the fitting is pretty old (+30 years) and likely to be imperial. Can I get a direct replacement to fit existing fittings?

TIA
Donald

 

[RichardS]

View attachment 56561
My Moody has this water separator fitted but no primary filter.
View attachment 56562
I've done several searches based on the part number stamped on the casing 7111-690 but Google hasn't returned anything for the -690. I'd like to replace the separator with a filter and glass bowl the assembly sits outside of the engine compartment.

Question is I suppose the fitting is pretty old (+30 years) and likely to be imperial. Can I get a direct replacement to fit existing fittings?

TIA
Donald

A brand new Racor FG500 would work a treat and they are still imperial 3/4 - 16 UNF. You might need adaptors but these are easy to source.

Richard

 

[pvb]

A brand new Racor FG500 would work a treat and they are still imperial 3/4 - 16 UNF. You might need adaptors but these are easy to source.

Richard

I'm far from convinced that a turbine filter designed for a flow rate over 200 litres per hour is ever going to work very efficiently on a small yacht engine. There are simpler - and cheaper - solutions.

 

[pvb]

My Moody has this water separator fitted but no primary filter.

I've done several searches based on the part number stamped on the casing 7111-690 but Google hasn't returned anything for the -690. I'd like to replace the separator with a filter and glass bowl the assembly sits outside of the engine compartment.

Question is I suppose the fitting is pretty old (+30 years) and likely to be imperial. Can I get a direct replacement to fit existing fittings?

TIA
Donald

Not sure it's a real CAV, it looks like a number of spurious water separators, and the cone inside yours appears to be upside down! See http://www.stardiesel.com/en/compl-watertrap-m14-ref-5864003-4686377.html and https://www.hc-cargo.com/default.as...uctid=090145&ecat=cat_detailview#!prettyPhoto

You can get similar filter/separator units in various imperial and metric sizes, see http://www.ssldieselparts.co.uk/filter-assembly-single-filter-assemblies-single-c-267_265_8.html for examples, and note that there's a spin-on filter option which some people prefer.

 

[Aja]

A brand new Racor FG500 would work a treat and they are still imperial 3/4 - 16 UNF. You might need adaptors but these are easy to source.

Richard

I wasn't exactly thinking of a +£150 filter with elements costing £25 each more like a CAV replacement. Engine only takes about three litres per hour so high consumption not a priority


Thanks
Donald

 

[Spuddy]

I've just switched from CAV to a Racor filter/water separator - forgotten model, might have been a 120, ASAP supplies will advise and sort out compatible connections as well - cost me about £100 incl new fittings and a length of new fuel hose.
I'd had a right fandango with the CAV a couple of years ago trying to fix an elusive air leak so finally went for easier filter swap on Racor although filter can costs more

 

[Malish]

Would second the comment re a CAV spin on being an option. The usefulness of the glass half of the trad CAV is somewhat overstated IMHO. The drain on the 496 is good enough to test for water or gunk and the ease of the spin on CAV 496 plus it's cheap price makes it a very attractive option. You can readily get it in imperial threads too, which I have a hunch is what the OP needs

 

[Aja]

Not sure it's a real CAV, it looks like a number of spurious water separators, and the cone inside yours appears to be upside down!.

It is a genuine CAV from the logo and markings on the top which aren't visible in the images. You're right about the cone being upside down. It was getting dark when I was putting the bits together after cleaning out the bowl.

I've had a look at the SSLDieselparts site and looks that there is a good range available. I only need a single take-off as the eber is tapped straight into the tank.

Not being an expert in fittings I assume I can go into a plumbing store and get adaptors and olives and things to make it all fit into existing pipes?

Donald

 

[Arcady]

The cone is indeed upside down. If you have room, why not just add a separate CAV spin-on or similar immediately after the water separator? It would give you the best of both st very modest cost.

 

[Aja]

Thought about that Arcady but I think introducing extra joints is introducing risk. I would rather keep things simple. I'm more concerned that there isn't a primary filter in the present system and buying a combined filter and water separator makes sense.
Thanks
Donald

 

[RichardS]

I'm far from convinced that a turbine filter designed for a flow rate over 200 litres per hour is ever going to work very efficiently on a small yacht engine. There are simpler - and cheaper - solutions.

I've one on each of my 30HP engines and I'm very pleased with their performance once I had stripped one of them down and re-assembled the internal valve in the correct order.

However, the point of my post was that modern filters still use imperial fittings.

I bought one of mine brand new for £100 and the filters are £5 each.

Richard

 

[GrahamM376]

Moody fitted the bowl as standard to many boats. I've left mine in place but fitted a spin on filter after it. Have had the CAV type split filter/bowl filters on previous boats and they're a pain in the proverbial if the filter needs changing at sea, too many ring seals. Spin-on much better.

 

[scottie]

Go into west of Scotland engineering they have a CAV leaflet with all the options and can source what you require

 

[Hydrozoan]

… I'd had a right fandango with the CAV a couple of years ago trying to fix an elusive air leak …

Would second the comment re a CAV spin on being an option. The usefulness of the glass half of the trad CAV is somewhat overstated IMHO. The drain on the 496 is good enough to test for water or gunk and the ease of the spin on CAV 496 plus it's cheap price makes it a very attractive option. You can readily get it in imperial threads too, which I have a hunch is what the OP needs

Yes, I suspect a minute air leak from the traditional glass CAV (296?) was the cause of a recalcitrant engine problem I had many years ago. I persisted with it, am very careful when changing filters and have had no subsequent problems - but a spin-on is attractive. I’ve never encountered significant amounts of water in the glass bowl, but I suppose the visibility is some advantage – are there any others that a switch to a 496 would lose?

 

[Malish]

Nope, is the same size as the complete 296 + glass bowl assembly so it probably has a bigger filter area (although the internal design is different). The metal head is the same size with the pipe fittings in the same location so is a straight swap.

 

[Pete7]

Donald they were supplied by International Marine Supplies and I bought a replacement from them 2 years ago. However, their website isn't working so perhaps they have gone under.

 

[Hydrozoan]

Nope, is the same size as the complete 296 + glass bowl assembly so it probably has a bigger filter area (although the internal design is different). The metal head is the same size with the pipe fittings in the same location so is a straight swap.

Many thanks.

 

[scottie]

Cav heads come in metric and American pipe threads

 

[philwebb]

You can get the CAV filters with the glass bowl on EBay for about £30. OK you might not want to change one in a rough sea, but if you use the fuel additive that kills the diesel bug you shouldn't have to. The advantage of this system is that the filters (CAV296 or equivalent) are very cheap and obtainable virtually everywhere. They are even used on some tractors. The glass bowl shows if you have collected some water- it does happen, and this came drained out below. Changing the filter you need to fit 2 new rubber rings, but once you have done it once it is easier.

 

[Hydrozoan]

You can get the CAV filters with the glass bowl on EBay for about £30. OK you might not want to change one in a rough sea, but if you use the fuel additive that kills the diesel bug you shouldn't have to. The advantage of this system is that the filters (CAV296 or equivalent) are very cheap and obtainable virtually everywhere. They are even used on some tractors. The glass bowl shows if you have collected some water- it does happen, and this came drained out below. Changing the filter you need to fit 2 new rubber rings, but once you have done it once it is easier.

Ideally you change 3 large O-rings IIRC, though filter kits typically come with only two. Our chandler used to stock the third and strongly recommended changing all 3 every time - one is a slightly different size from the other two.