Fuel Filters

Stemar

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On Saturday, we got hammered coming back from Langston to Portsmouth. It takes a lot to wash the windows on a Snapdragon 24, but beating home in what Solent CG described as 6 gusting 7 did it! (So that was why there were no other boats out there... /forums/images/graemlins/shocked.gif /forums/images/graemlins/shocked.gif)

Great fun, but we paid for it as the engine died coming up to No 4 buoy and we had to come into the harbour under sail, which is an, err... interesting... experience in a gusty westerly with the wind coming from all direction or none and a fastcat bearing down on us.

Predictably, it was the primary fuel filter. I had the necessary filter and the tools, but I reckoned it was just too bumpy outside the harbour, especially as my crew had been out with me three times in as many years, so couldn't really be left to handle the boat on his own for any length of time.

Next morning, the ten minute job turned into a two-hour curse-fest as the top sealing ring refused to go in smoothly and stay in long enough to get everything back together. It would have been an absolute nightmare at sea, blowing a hooly and in the dark /forums/images/graemlins/tongue.gif

I don't want to have to go through that again. I'll try and avoid it by keeping the fuel tank over half full in future. Cleaning it out is problematic, cos the only ways in are through the filler and the fuel supply and return. It's a metal tank glassed in the back of a locker, so removing it would involve an angle frinder and, probably, the tank in several pieces. Ideas for cleaning it would be welcomed!

I want to have 2 filters in parallel, so I can switch to the spare by opening and closing a few valves if it happens again, but the CAV filters are £25 plus, even on eBay, and, as you have probably gathered, I'm on the ham-fisted side when it comes to things mechanical. I really don't feel comfortable with all those sealing rings and bits that have to line up, so I'm looking wistfully at the spin-on cartridge on my car. I could change that (accessibility aside /forums/images/graemlins/frown.gif ) in 30 seconds, with a good chance of no more than a few drops of diesel spilt.

So, to come to the point (at last!) What are the disadvantages of going to my local breakers and unbolting a couple of complete units from, for example, a pair of Transits? I've never seen any water in the sight glass of my current CAV unit, whose plastic drain tap would certainly snap if I tried to undo it, and I've seen spin-on cartridges with drainage taps if I did ever have a problem.

Fuel is gravity fed and the engine is a Volvo 2003.
 
Had the same problem and it was bad enough in harbour. I switched to Racor spin on filters ( they work like an oil filter, so no messing with different rubber rings and you can whip them on and off with ease. You will need a conversion head for your CAV unit, but it's easy to fit. ASAP Supplies are the people to talk to ( as advised in other posts) The Racor units are more expensive, but I think it's worth the hassle, thinking of the time when you may need to solve that fuel blockage quickly.
 
I had similar problems with my AC fuel filter as no water collected in bowl.
This was cured by changing the fuel lines that allowed the fuel to enter the bottom of the bowl then upward through the filter.
Water cannot get through oil impregnated filter elements.
 
I would go for the Racor 500 series filter. Quite expensive, but a doddle to change the element.
The 120A & 140 would probably be a better choice costwise (and more suited to smaller engines) These use the spin on type element.

Regarding the CAV filters. You can make the job a lot easier by holding the sealing rings in place with some grease.
There ya go..... Col's top tip of the day /forums/images/graemlins/laugh.gif
 
You make it sound idiot-proof . . .

Sorry to cash in on your problem Steve BUT . . .
Do you all seriously think that I could improve the filter-changing part of the servicing exercise (which was very easy moored alongside and watching someone else do it!) by adapting the CAV filters as above?

Engine is Perkins 6.354 120HP.
 
Re: You make it sound idiot-proof . . .

I too, have had problems with sealing rings. The rings are distorted by being crushed into a rather small filter box. It may help if the rings are removed and stored flat for a few weeks, to regain their shape.

On my Perkins 4108 I find it essential to lubricate the small central O ring, as the ring can roll out of it's groove and be damaged during assembly.

Philip
 
Re: You make it sound idiot-proof . . .

Just as well I read this thread, because I was planning on changing to a CAV 296 type filter this winter. I've never thought of them as being troublesome. However firstly they're the only sort I've ever changed, and secondly I've only done so on plant, not at sea.

In their favour - cheap replacement elements (£2 each from MF dealers for example), and the ability to see contamination.

These guys do an assembly with built-in primer pump ...

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=4607269039&fromMakeTrack=true

Any ideas for a low-cost equivalent with cheap spin-on filters?
 
Re: You make it sound idiot-proof . . .

If you buy the filter head with the built in primer pump remember to buy a tube of silicone sealant so's you can bodge the pump when the diaphragm fails (which they do with monotonous regularity).
A better option is to put a primer bulb in the line - it's cheaper and more reliable, and easy to change if it fails - and carry a spare.
Most vehicle manufacturers have gone down this route.

We retro-fit them to broken-down vehicles all the time.
 
Re: You make it sound idiot-proof . . .

Thanks for the ASAP tip, Lots of interesting bits there!

The Racor units do seem to be the biz, but not cheap. I'm thinking more along the lines of a trip to my friendly local car breakers to get a pair of something suitable with spin-on filters that are sold by the million. I hope to pay a fiver each, but it's a long time since I went to a breakers, so pehaps I'm being naive.

I've never had any water in the separator bowl, so are there any real disadvantages to doing away with it?
 
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