KAD32 - Fuel Filters - frequency of change

[boy boater]

The recommended change period for the fuel filter and fuel pre-filter on my KAD32 is every 200 hours/at least once a year.
The engine has done 30 hours in the 12 months since I last changed both filters.
The pre-filter has a tap at the bottom for draining off any water found in the fuel, when I tested this I found none.
In view of the low hours run, i.e 30 vs 200, what problems, if any, can I expect from leaving it for another 12 months before changing the filters assuming I don't exceed 170 hours running time in the interim?
Do filters degrade with time as opposed to usage, i.e. throughflow?

 

[Kawasaki]

For peace of mind and for what they cost change the pre filters annually at least.

 

[Philiz]

Just because there's no water, it doesn't mean they're not dirty. If your filters give you trouble when you're at sea, you'll wish you'd changed 'em.

For what it costs change them anyway, better safe than sorry.

Also, don't forget to carry spare filters.

 

[boy boater]

I agree, Philiz, that no water doesn't mean no dirt - but dirty after 30 hours?
And if this is likely to be so, then why isn't the recommended period for change not 30 hours instead of 200 hours?

 

[RIN]

The pre filters should be coarser (and a lot more expensive) than the fine primary filters so you could get away with changing them every two years, changing the primary (cheaper) filters every year.

Philiz is right about keeping spare filters on board ( we have a spare pre filter for each KAD32 and several primary filters (Fram P5770) for each engine)

Whilst on the subject, if you have room, keep a spare oil filter (Fram PH2861B or two in the boat in case one gets clogged.

 

[PaulGooch]

The pre filters should be coarser (and a lot more expensive) than the fine primary filters so you could get away with changing them every two years, changing the primary (cheaper) filters every year.

Philiz is right about keeping spare filters on board ( we have a spare pre filter for each KAD32 and several primary filters (Fram P5770) for each engine)

Whilst on the subject, if you have room, keep a spare oil filter (Fram PH2861B or two in the boat in case one gets clogged.

Sorry, but i don't think that's correct. Pre-filters will almost always block first, especially with bug problems. The secondary filter is finer (or should be) and on my boat costs three times as much as the primary filter.

We keep several primary filters and one secondary filter onboard.

Not so sure about the oil filter, i suspect that if it blocked up you'd need a new engine. The first you'd know is when the oil light came on and the buzzer went off, you'd be very lucky if you could shut the engine down before the crank seized.

Anyway, to the OP, change the filters and do whatever other maintenance the schedule specifies. Skimping on maintenance with a boat is a bad idea. Problems when selling boats with bad service history, problems with having to call the RNLI out when it goes pear shaped and breakdowns/problems generally take the pleasure out of it al.

 

[Philiz]

I agree, Philiz, that no water doesn't mean no dirt - but dirty after 30 hours?
And if this is likely to be so, then why isn't the recommended period for change not 30 hours instead of 200 hours?

Depends on the state of your tank and the fuel you put in it.
Your filter may be perfectly fine, leave it if you like, I'm just suggesting it's better to change it now rather than when you're sitting out at sea, dropping all your tools in to the bilge and wondering if you'll get it done before you're aground.
For what it's worth. I don't know anyone who leaves their filters for 200 hours.

 

[RIN]

Sorry, but i don't think that's correct. Pre-filters will almost always block first, especially with bug problems. The secondary filter is finer (or should be) and on my boat costs three times as much as the primary filter.

We keep several primary filters and one secondary filter onboard.

Not so sure about the oil filter, i suspect that if it blocked up you'd need a new engine. The first you'd know is when the oil light came on and the buzzer went off, you'd be very lucky if you could shut the engine down before the crank seized.

Anyway, to the OP, change the filters and do whatever other maintenance the schedule specifies. Skimping on maintenance with a boat is a bad idea. Problems when selling boats with bad service history, problems with having to call the RNLI out when it goes pear shaped and breakdowns/problems generally take the pleasure out of it al.

Thats interesting, my Racor Prefilters R25T/245 cost over £20 each (10 micron) and my engine filters (primary - which I believe to be finer)) are only a £5 each - not much more if I bought the volvo part.

The oil filters are a good bet to keep on board as they do get clogged over time. I had a severe drop in oil pressure on the port engine half way along the Seine, finished the leg on one engine and a new filter fixed the problem. Not sure how I would have got an oil filter on a Saturday afternoon in France , but having one in the locker was useful

 

[Philiz]

Thats interesting, my Racor Prefilters R25T/245 cost over £20 each (10 micron) and my engine filters (primary - which I believe to be finer)) are only a £5 each - not much more if I bought the volvo part.

Is terminology causing confusion here? Isn't a pre-filter and a primary filter the same thing? I though the general set up was a primary (or pre-) filter and secondary filter? But I stand to be corrected.

 

[TAIC]

i believe you are correct Philiz.

 

[lovezoo]

Thats interesting, my Racor Prefilters R25T/245 cost over £20 each (10 micron) and my engine filters (primary - which I believe to be finer)) are only a £5 each - not much more if I bought the volvo part.

So £25 for the annual cost of new filters, versus around £7,000 for a secondhand KAD32? I know what I would do... Oh, and I'd change the oil in the outdrive.

 

[RIN]

So £25 for the annual cost of new filters, versus around £7,000 for a secondhand KAD32? I know what I would do... Oh, and I'd change the oil in the outdrive.

2 x KAD32s

You can spend as much money as you like on a boat.

The smart thing is to draw a line somewhere. As far as the fuel filters go, I've never had any trouble doing this i.e. replacing the engine filters every year and the large prefilter every other year. As stated I carry 2 spare prefilters and also 6 or 7 engine filters. Never yet had to replace a fuel filter outside of regular annual maintenance and fingers crossed the engines have not yet self destructed

Quite agree with the outdrive oil though, that gets changed every year

 

[boy boater]

According to the V-P Operator's Manual for the KAD32 et al the first filter after the fuel tank, the one with provision for draining off any water, etc. (i.e. a drain tap/cock/plug at the bottom) is termed the pre-filter.
Interestingly, the pre-filter is referred to in the manual as an accessory which suggests it is up to the boat builder as to whether one is fitted or not?
The filter mounted on the port side of the engine block, and taking fuel that has already passed through the pre-filter, is merely termed the filter.

 

[boy boater]

ps Thank you all for a most interesting and useful debate.

 

[PaulGooch]

Thats interesting, my Racor Prefilters R25T/245 cost over £20 each (10 micron) and my engine filters (primary - which I believe to be finer)) are only a £5 each - not much more if I bought the volvo part.

The oil filters are a good bet to keep on board as they do get clogged over time. I had a severe drop in oil pressure on the port engine half way along the Seine, finished the leg on one engine and a new filter fixed the problem. Not sure how I would have got an oil filter on a Saturday afternoon in France , but having one in the locker was useful

Just to answer the other posts about terminology, IMO the first filter is the pre-filter or primary filter, the next one is the secondary filter.

As you rightly say, the second one if finer. My re-filter/primary filter is a Racor 500 series turbine, elements are about £7. The secondary filter is a Toyota (Nanni), prices vary depending if you buy original Nanni, Toyota or a pattern part (i go for the pattern), but all are more than £7.

Interesting (as you say) that our prices are almost opposite. Also interesting to read of your oil filter story. I've always been unlucky enough to need an engine rebuild with blockages, although that's always been with car engines.