Originally Posted by billfisher
Oh yes of cause, sorry didn't think it through. So if one could seal the breather and filler then the problem might not occur? I suppose you risk popping over seals that aren't designed for the high pressure.
Oh yes of cause
just that point alone is enoughMaximum flow rate 45 litres per hour.
Spot on Billfisher, the breather is where the air and moisture is sucked in.... the more humid, the more moisture...simple.
Sealing the vents will most probably split the tank.
As mentioned above, hot weather/ cold weather ... who cares.... condensation is caused by the same paramaters - i.e. a quick fluctuation in temperature, resulting in water vapour forming into droplets.
The amount of water... as stated will vary from situation to situation.
From a report I read a few years back, a plastic tank exposed to the sun in Qld, quarter full of fuel, produced 10 litres of water in 2 weeks.
My point.... who cares to what "millilitre" of water is produced..... condensation is a real problem, has the potential to produce large amounts, and can be prevented / minimized by keeping tanks full.... end of story.
Mantaray, my old friend, I would ask a favour of you, for the benefit of everyone, including yourself.
Your questions are always legitimate, but double sided.... meaning that they can easily be interpreted as being cynical. They give the reader the impression that you "scoff" at what has been mentioned, hence the amount of people that retaliate against you.
For Example:
CAV Filters.
You read my post, where I stated that I have had very good success with CAV filters, which I post from my many years of experience on the water.
You state; "now why would anybody want to use a CAV filter on an outboard?"
So, should I interprate this as:
a) "What idiot would use a CAV filter on an outboard?"
or
b) I , Mantaray, personally do not understand filter systems and would like to ask Grand_Marlin some further information on why he considers a CAV filter in particular to be best for an outboard.
Take this as you will Mantaray, but for the benefit of all, I ask you to consider broadening and defining more precisely your required intentions, and outcomes from your posted comments.
Thank You,
Pete
from my understanding
cav have a finer micron rating, the reason for better flitration, slightly less flow because of the micron size, better able to stop water BUT there seems to be some speculation of them causing some seperation of premix fuel than the racor
So if your flow rate was too high you could run 2 filters in paralel, problem solved
been running cav's all my boating life and never been stuck any where with a fuel problem of any sort apart from a 4hp johno that the fuel pump failed on
cheers
blaze
no my question was "why would anybody want to use a CAV filter on an outboard?" that's what i said and that;s what i meant to say and it really doesn't matter much about life long experiences as these filters were never intended or designed for outboards and blaze has probably got a valid and real point.
why would you use something that was never designed or intended for outboards when there are specifically designed filters/separators made for the job that handle the job that much better and with less speculation.
oh and mr marlin i understand filter systems perfectly well, hence the question and if you read any cynical scoffing into the original questin then perhaps you are looking too hard expecting to find some hidden meaning!
so pete if a cav has a flow rate of 45 litres per hour then most medium to upper size outboards would think they were drinking though a straw with a knot tied in it! wouldn't they?
Mantaray,
Firstly, read your own writing and dont twist things.
Re: Water in Fuel
« Reply #8 on: Yesterday at 17:30 » now why would anybody want to use a CAV filter on an outboard?
CAV filters are a fuel filter... designed for filtering fuel.
Outboards run on fuel.
CAV filters are used for their outstanding water separating ability.
If the specific marine / outboard filters are going to leave you stranded, then I am not interested in whether or not it is specifically designed for the marine environment and outboards.
I want products that I can trust my life to.
The only part of a CAV filter that is affected by the marine environment is the bolt that joins the filters together. It is cadmium plated, not stainless. A wipe of Lanolin fixes this problem
Mr Mantaray... experience is everything and only a complete fool would question this.
The advice I offered you in good faith re: your double sided, vague comments has fallen on deaf ears... so be it.
45 litres per hour flow rate refers to the peak efficiency of the filters ability to filter or separate water from the fuel.
It is not refering to the maximum amount of fuel it will allow through the filter. Hence why outboards (up to 130hp) that I have used, do not in the slightest starve for fuel.
The CAV filters are so efficient, that they separate water perfectly in situations where maximum fuel flow rates are up to 90 litres per hour. (my experience)
Racor which was specifically designed for the marine outboard with higher fuel flow rates, let me down on 3 separate occasions, with 3 different motors.
CAV filters are that efficient that they have been known to separate oil from a premix.
You will note that I asked if the motor in question was oil injected....and it most certainly is.... so no problem there.
Twin filters for higher flow rates?
Very good point Blaze.
I did this exercise on my 18ft Sharkcat that ran twin 110 Evinrudes, for exactly the reasons mentioned. If the first filter allowed any water through, then the second would pick it up.
In practice, the first CAV filter took all the water out and deposited it into the glass bowl. In two years, the second filter never received a drop of water on either motor... again with fuel flow rates of up to 90 litres per hour.
You are entitled to not use CAV filters for whatever reason you like.
Hopefully my experience has removed the speculation that your inexperience has created.
Kind Regards,
Pete
that's not efficient that simply probably using the wrong filter for the purpose! now any fool knows thatCAV filters are that efficient that they have been known to separate oil from a premix.
by the way blaze was referring to filters in parrallel not series pete as you sound like to did, which by the way (series) is the recommended proper configuration for a a good filter system
so what your saying pete is that up to 45 litres per hour the water is handled completely and at 90 litres per hour there's water in the fuel? as the filter is at twice its capacity to handle the water totally?45 litres per hour flow rate refers to the peak efficiency of the filters ability to filter or separate water from the fuel.
It is not refering to the maximum amount of fuel it will allow through the filter. Hence why outboards (up to 130hp) that I have used, do not in the slightest starve for fuel.
Well thank you everyone for your comments I am very impressed with all offerings.
Yesterday I sat and watched ET on a charter boat up in the Territory and the thought crossed my mind that perhaps owning a boat is more trouble than its worth and that maybe I should look at local cherter boats. I probably won't get to that as the family are more keen to keep a boat than I.
At this time I'm thinking of actually moving the boat on and replacing it with a Cruise Craft. The wife and I both share the thought that we now feel less confident with the boat/motor combination and perhaps it is better to simply make a change - no I'll keep the wife and change the boat that is!
Peter A
Ok... I will reword that.... the filter elements supplied, for use with straight petrol on the CAV filters are not suitable for premix as they can strip oil from the premix.
So yes, right filter element for the right job.
There is a CAT element available for premix petrol.
And I am saying that the filter has been proven to work perfectly at twice its stated capacity. I also stated that there was no water going past the primary filter, in an "in series" installation. The secondary filter had not collected one drop of water in two years service.
I didnt pick up on Blazes "parallel" comment. I am assuming he meant series, as a parallel filter system for a single outboard is not really feasible anyway.
Assuming we are on the same wave length with a parallel system - i.e. running two separate fuel lines from the one tank, to two separate filters and then teeing them into one before the motor.
Anyway, the point I am would like to stress, is the fact that CAV filters are more than feasible for outboards - they are not a joke like you imply.
Hi Pete
yeh, I suppose I was trying to think outside the square in reguard to running paralell filters, it would be easy to do and the fuel would take the path of least resistance. Using this system eliminates the arguement of limited flow rate (I've never seen a problem). You are very correct in saying that in series is the best for filtration (I've pulled a lot of double filters off in my time in cant recall a case of water in number2, diesel mechanic by trade, too many years in the job)
cheers
blaze
G'day Blaze.
Sorry mate, I see where you were coming from, but I wasnt having a shot by any means. It is feasible and would correct any fuel flow problem, if it were an issue on a large outboard.
I would say a couple of 225 v6's would test them, but I also know they are fine with v6 150 yammies.
Rather tiresome trying to prove a point about CAV filters, but anyway...
If I thought Racor was a good product, then I would say so. And the only reason I dont is by getting caught out with Racor. In all 3 instances, once they were changed to CAV, without even draining the tanks, there were no more water problems.
Cheers
Pete
ps... do you fish the St Helens Game Fish Classic?
no probs pete, dont fish comps. prefer less crowded waters
cheers
blaze
Well I didn't expect such a "heated" reply to my question on CAV filters but I'm happy with the replies.
Grand_Marlin a question if I may, In the quote from the BIAS catalogue it states "For petrol or petrol/oil mixtures use optional extra Cat. 666P Element Kit."
Do I assume the filter that comes standard with the unit is diesel ONLY and and i need to purchase the option (Cat. 666P from above) as it states "Petrol or Petrol/Oil"
or
Can i use the standard filter, as my Suzuki 85 is oil injected?
The reason behind the question is that my rig uses a CAV system and i need to replace the filter (not sure when it was done last as I bought it in DEC 05)
1 more question, are all CAV replacement filters the same, ie do I need to match the brand with my current make or will the BIAS filter fit.
Thanks.
cav 296 is the element I have used for years
100% guaranteed (I think!) that it is condensation as a result of your parking the unit in the open for lengthy periods. I have a Whitley Sovereign with an under-floor 250 Litre S/S tank and it has accumulated water from the day it was new. It is raised out of the water via an air driven lifting cradle but being close to the water the tank gets pretty cold all the time.
I have demolished the entire fuel system from the cap to the carby entry (5.8 L OMC petrol) and had no luck whatsoever clearing the water. Added 5 L metho and all sorts of crap that is supposed to get the H2O out. Nuffing worked!
So what did I do? Ran the motor at least once every week for a few minutes, drained the fuel fuel water collection bowl each time and have not had water for over a year!
Or get a water seperator installed in the fuel line and make sure you get every drop!
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