Changing CAV filters

[model 10]

Originally Posted by sanibel sailor

put a good Racor upstream and you will rarely need to change it. I raised my CAV for access and put a drain in the bottom. Do not know how it works as I have not had to change it in 5 years.

How many hours in 5 years? If you use a 10 micron in your Racor you are getting dirt in your engine. Who knows what the micron rating for the CAV element is? I've heard it could be as many as 20 micron. You can get a spin on in just about any micron rating you want.

[Jim Cate]

Racors are good filters, no argument from me, but in much of the world they are difficult to impossible to source locally, and even in the states they are dear. The lowly CAV is available world wide and is inexpensive. This explains their common usage!

I've used them for years, and don't see what the issues are with changing them. If one can not get a small pot or bucket under it for draining, perhaps it is easier to move it a bit than to refit for a Racor... if you can find one!

Jim

[olaf hart]

Anyone have a line to a replacement plastic bottom drain screw on a CAV?
Mine is broken and stuck I. The thread, I don't use it but would like to drill it out and put in a new one, just in case.

[sanibel sailor]

Originally Posted by Guy

How many hours in 5 years? If you use a 10 micron in your Racor you are getting dirt in your engine. Who knows what the micron rating for the CAV element is? I've heard it could be as many as 20 micron. You can get a spin on in just about any micron rating you want.

I mostly race, so use the sails rather more than the engine. About 200 hrs in 5 years. New tank, replaced all fuel system components including filler O-ring at same time. Meticulous when fueling about cleanliness. Looked at Racor filter a year ago and it was pristine, fuel in bowl looks perfect. Picture is 6 months ago, looks same today.

I do not think I am getting dirt in the engine.

[colemj]

Originally Posted by Jim Cate

Racors are good filters, no argument from me, but in much of the world they are difficult to impossible to source locally, and even in the states they are dear. The lowly CAV is available world wide and is inexpensive. This explains their common usage!

I've used them for years, and don't see what the issues are with changing them. If one can not get a small pot or bucket under it for draining, perhaps it is easier to move it a bit than to refit for a Racor... if you can find one!

Jim

I don't know about availability world-wide for Racor elements, but we have found them absolutely everywhere in the Caribe, Central and South America. In the US, a replacement element costs ~$8, and we have paid upwards of $12 for one in Central America. CAV replacements may be less expensive (I don't know), but still the Racor costs aren't onerous.

I guess I'm just the type of person who will never develop the skill for replacing CAV filters. In my first two attempts (two engines), I somehow could not get the stupid seals to seat properly and not leak. In trying to tighten one of them, the glass bowl simply broke in pieces and fuel dumped all over the place. The other one required disassembly/reassembly three times to get it to seal correctly. And even if it all went well, one would still have fuel-soaked hands and housings to clean. These filters are probably why many boats smell of diesel.

Frankly, they are the most idiotic design I could imagine for something with such a simple purpose. Maybe the clue lies in the fact that these are LUCAS-CAV filters. The "Lucas" part has generally been dropped for marketing reasons I'm sure everyone can imagine…

Mark

[model 10]

Originally Posted by sanibel sailor

I mostly race, so use the sails rather more than the engine. About 200 hrs in 5 years. New tank, replaced all fuel system components including filler O-ring at same time. Meticulous when fueling about cleanliness. Looked at Racor filter a year ago and it was pristine, fuel in bowl looks perfect. Picture is 6 months ago, looks same today.

I do not think I am getting dirt in the engine.

That looks nice and clean

[Stu Jackson]

Originally Posted by colemj

Frankly, they are the most idiotic design I could imagine for something with such a simple purpose. Maybe the clue lies in the fact that these are LUCAS-CAV filters. The "Lucas" part has generally been dropped for marketing reasons I'm sure everyone can imagine…

Mark

So well put.

Thanks.

[barnakiel]

I cut a gallon water bottle half open and use the bottom part as an empromptu sump (tying it on a string below the filter). I spill some oil but very little amt only. I end up smelly anyways which is why I do not really like CAV filters.

b.

[Jim Cate]

I don't know about availability world-wide for Racor elements, but we have found them absolutely everywhere in the Caribe, Central and South America. In the US, a replacement element costs ~$8, and we have paid upwards of $12 for one in Central America. CAV replacements may be less expensive (I don't know), but still the Racor costs aren't onerous.

Mark, I just did a quick cruise through the West catalog on line, and replacement Racor elements were a lot more than eight bucks... depending on model, 20 to more than 40 dollars each. I don't know much about them, and may have been looking at the wrong items, but I didn't see any for eight dollars.

And none of the normal chandleries in Oz seem to stock them. I can get CAV elements at any auto parts store for 6-8 bucks Australian... shared a carton of them with another cruiser a few years ago and they were about 6 bucks each in that quantity.

I'm not knocking Racor. As I said, I think they are good kit, but some places they don't make "no-brainer" sense to me. And I don't find the CAV all that hard to manage.. but i put mine where they are easy to work on.

Cheers,

Jim

[colemj]

These are the ones I'm talking about: http://www.amazon.com/gp/product/B00...AX3SCZ592BC6F0

$8 there. Defender has them for $12, but we find them on the shelves of mom and pop marinas for <$10. West Marine wants $16, but who buys something like this from WM? It is like buying bolts and screws there.

Certainly get filters that are most readily available in your area, but our CAV's were mounted with about the easiest access one can have and I still had issues with them sealing, breaking, and changing them. Terrible, awful design IMO.

Mark

[a64pilot]

I grew up changing the CAV filters on farm tractors. I guess I got used to seating those flat O rings. Do keep a spare glass bowl though, because inevitably one day you will over tighten or drop the thing.
Point being I guess if you grew up wearing lace up boots, it's not a bother, but if you never wore them then I bet doing all that lacing is a real PIA.
But, if you are a frugal sailor, be hard to justify buying a new Racor to replace the Cav's for convenience sake.

[colemj]

I consider myself frugal and I had no problem with that decision. It only takes one broken bowl on a gravity fed fuel system to make one part with their money....

Mark

[Stu Jackson]

A recurring discussion.

CAVs - few positives except the cost of the filters, unless you're Jim & Ann and have placed them properly.

Racors: there are two kinds: the cheaper filters have a very expensive housing; the more expensive filters have a less expensive housing.

Dahl - like Racor but without the choices IIRC.

But when all is said and done, many have remarked that the cost of filters over time is tiny. While bulky items, use of quality fuel funnels if necessary, makes changing filters on a sailboat a once a year, or even once every two years, a situation where spare filters can be brought along. Even if twice a year changes are necessary. Of course, it depends on how long one plans to be "out there," but just trying to put this in perspective.

I have four spares on board, I change once every year and a half, and I live where I can buy them, but still... I put anywhere from 1-200 hours a year on our engine. When I change them they're still clean.

And yes, some will say "But what if I get a bad batch of fuel?" See "... use of quality fuel funnels..." Keep the nasties out.

I am sure there will be conflicting opinions, but these are just my opinions.

[colemj]

Originally Posted by Stu Jackson

But when all is said and done, many have remarked that the cost of filters over time is tiny. While bulky items, use of quality fuel funnels if necessary, makes changing filters on a sailboat a once a year, or even once every two years, a situation where spare filters can be brought along. Even if twice a year changes are necessary. Of course, it depends on how long one plans to be "out there," but just trying to put this in perspective.

I agree with this. I just changed our two filters after 6 yrs, which is why I had recent experience buying Racor replacement elements ($8.25 each at a small marine store in Florida). I know - 6 yrs is excessive, but we do have vacuum gauges on them and a separate polishing system that gets run frequently.

But even changing them once/yr at an outrageous $20 isn't very onerous even for a frugal person. I can tell you that the cost of oil pads and detergent cleaning up one mess caused by the design of that CAV filter cost WAY more than I will ever spend in the differences between replacement filters.

I just don't understand how any engineer could have come up with that Lucas-CAV design and get it pass his team, management and marketing without anyone saying "WTF"?

Mark

[Sailmonkey]

It can actually get worse than the cav.......