Changing Diesel fuel filters

clyst

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Normally I can't be arsed to get covered in diesel doing this simple job however this year to save a bit of dosh I thought I'd do it myself .
Now then the set up is the usual pre filter and an engine filter .They are bog standard CAV filters so off to tHe chandlers to purchase a pair of elements . Unbeknown to me the pre filter has a glass bowl on the bottom whereas the engine one is just a straight filter sandwiched between top housing and base plate . what I don't understand is that the standard filter comes with various little O ring and Two for the top and bottom of the filter . no problem for the engine filter but I'm one o ring short for under the glass bowl. Apparently the lower one has to be bought separately !! It was cheaper for me to buy another filter kit than a separate o ring . can anyone explain as they are both standard CAV filters this should be ? I question whether the info I was given is correct .
 
Yes it's common for you to be effectively one new O-ring short.

However as you should be changing the fuel filter at least once a year, and the O-rings will last 2 years easily you just have to alternate which ones you renew.
No big deal.

One other minor point is that if you ever venture on the inland waterways including major rivers and need to comply with the BSS, it won't pass with a glass bowl. Only alumimium bowls approved, they don't crack (with consequent pollution risk).

I know everyone's been using glass bowls for years no problem but that's the way it is, for BSS anyway.
 
Yes it's common for you to be effectively one new O-ring short.

However as you should be changing the fuel filter at least once a year, and the O-rings will last 2 years easily you just have to alternate which ones you renew.
No big deal.

One other minor point is that if you ever venture on the inland waterways including major rivers and need to comply with the BSS, it won't pass with a glass bowl. Only alumimium bowls approved, they don't crack (with consequent pollution risk).

I know everyone's been using glass bowls for years no problem but that's the way it is, for BSS anyway.

And usually coding too as during a fire they can crack and obviously spill the fuel onto the fire. The fact a blockage goes unnoticed and potentially leads to engine failure doesn't matter...

W.
 
I think St Cunliffe makes a mention of the glass bowls in this month's YM. If like me, your CAV filter with glass bowl is outside the engine compartment you are ok. Mine is in the locker just after the fuel tank. The risk is if the glass bowl is in the engine compartment and shatters for whatever reason becoming a fire hazard.
 
Normally I can't be arsed to get covered in diesel doing this simple job however this year to save a bit of dosh I thought I'd do it myself .
Now then the set up is the usual pre filter and an engine filter .They are bog standard CAV filters so off to tHe chandlers to purchase a pair of elements . Unbeknown to me the pre filter has a glass bowl on the bottom whereas the engine one is just a straight filter sandwiched between top housing and base plate . what I don't understand is that the standard filter comes with various little O ring and Two for the top and bottom of the filter . no problem for the engine filter but I'm one o ring short for under the glass bowl. Apparently the lower one has to be bought separately !! It was cheaper for me to buy another filter kit than a separate o ring . can anyone explain as they are both standard CAV filters this should be ? I question whether the info I was given is correct .
Hope you didn't pay chandlers prices - they're much cheaper at local diesel mechanics.
 
Fascinating. Our boat when we bought her was coded, with a glass bowl CAV pre filter in the engine compartment....

From what I have seen on a few commercial boats coding is a check list joke:
Radar reflector on a big RIB, tick, never mind that it is mounted horizontally so good returns fore and aft but nothing 20 degrees either side of the centre line
Storm jib on a charter yacht, tick, can it be set - off course not, it has hanks and there is no stay to put it on.
Big Mainsail on a broad transom charter yacht with only two rows of reef points (other surveyors require three) and boat becomes unmanagable in only 30 knots of wind.

Returning to comments about glass bowls, many years ago a friend in a remote rural area powered his house with a big Bedford diesel and generator, fortunately in a shed away from the house. One night the genny stopped, investigating he dropped the kids torch across the terminals of the starter batteries. Torch had magnesium alloy body which flared and cracked the glass filter bowl that was just over the batteries. The gravity feed tank had been filled a few days before and they burnt 600 gallons of diesel that night. No fatalities but my friends heart briefly stopped in the ambulance on the way to hospital.
 
From what I have seen on a few commercial boats coding is a check list joke:
Radar reflector on a big RIB, tick, never mind that it is mounted horizontally so good returns fore and aft but nothing 20 degrees either side of the centre line
Storm jib on a charter yacht, tick, can it be set - off course not, it has hanks and there is no stay to put it on.
Big Mainsail on a broad transom charter yacht with only two rows of reef points (other surveyors require three) and boat becomes unmanagable in only 30 knots of wind.

Returning to comments about glass bowls, many years ago a friend in a remote rural area powered his house with a big Bedford diesel and generator, fortunately in a shed away from the house. One night the genny stopped, investigating he dropped the kids torch across the terminals of the starter batteries. Torch had magnesium alloy body which flared and cracked the glass filter bowl that was just over the batteries. The gravity feed tank had been filled a few days before and they burnt 600 gallons of diesel that night. No fatalities but my friends heart briefly stopped in the ambulance on the way to hospital.

A series of tragic events but I'm surprised that being a genny house that there was no auto extinguisher system fitted similar but on a larger scale to that fitted in my engine compartment. what did the insurance company have to say ?


A about the genny being fed via a filter with a glass bowl within the genny house .?

B about having no firefighting system or atleast an ineffective one ?
 
Playing devils advocate now...

Perhaps it's time to change the whole way surveys for coding/licensing are done? Instead of the owner chosing and paying the surveyor hey should pay the MCA (for example) who then allocate a surveyor.

That way there is no bias towards the owner by the surveyor looking for return business. All surveys would be conducted to a standard format removing individual interpretation of rules.

I've experienced bother ends of the scale where the surveyor literally picked up on a corroded screw on a hose clamp to one that would basically sign anything as long as he got chocolate biscuits and coffee on arrival.

W.
 
A series of tragic events but I'm surprised that being a genny house that there was no auto extinguisher system fitted similar but on a larger scale to that fitted in my engine compartment. what did the insurance company have to say ?

It was 1971 or there abouts, a DIY conversion of an old water mill into a dwelling and no insurance.
 
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