Filling oil filters before fitting....do you?

DavidJ

DavidJ

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Hi
Drained the oil in my KAD43's yesterday and replacing the filters and filling with oil today. I usually fill the new filters before fitting but it does add to the general bother, messiness and probability of spills of the operation.....is this really necessary? I wonder what the professionals do?
 
DavidJ said:
I wonder what the professionals do?
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waste of time, dont do it.

As to professionals I know of one that just uses T-Cut , quick wipe over of the filter with a rag in case anyone has invisible marked it and 'change oil' ticked on the service sheet leaving time to rummage around to see if there is anything worth steeling :eek:

Useless piece of carp didnt even get that right, as he turned it to T-cut it he forgot to tighten it up afterwards .
 
My oil filter goes on horizontally, so trying to fill it would be even more messy than it already is. The oil pump will do that as soon as you start the engine anyway.

I do pre-fill fuel filters though, to reduce the amount of air to bleed out.

Pete
 
My engine has a mechanical "pull- stop" so after changing the oil filter I turn the engine on the starter with the "pull-stop" out until I see pressure on the oil pressure gauge, then push it in and the engine starts. This ensures clean oil is circulating before starting.

On some engines it may be necessary to shut off the raw water intake when doing this to prevent filling the engine with water from the exhaust. Then turn the water back on before starting the engine.
 
prv said:
My oil filter goes on horizontally, so trying to fill it would be even more messy than it already is. The oil pump will do that as soon as you start the engine anyway.

I do pre-fill fuel filters though, to reduce the amount of air to bleed out.

Pete
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Thanks for your replies but I will add a comment to Pete's thread. 6 months ago I asked the exact question but about fuel filters and I got a resounding don't do it from all. In short the contamination in fuel is microscopic and you are likely to introduce contaminants from your can into the wrong side of the filter....so fit dry and in my case 200 pumps to bleed pre and engine filters.....hope this helps.
 
prv said:
My oil filter goes on horizontally, so trying to fill it would be even more messy than it already is. The oil pump will do that as soon as you start the engine anyway.

I do pre-fill fuel filters though, to reduce the amount of air to bleed out.

Pete
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+1

I don't have to bleed the fuel filters even though it does get VERY close sometimes with the engine JUST about to stop, but it always keeps going.
 
DavidJ said:
Thanks for your replies but I will add a comment to Pete's thread. 6 months ago I asked the exact question but about fuel filters and I got a resounding don't do it from all. In short the contamination in fuel is microscopic and you are likely to introduce contaminants from your can into the wrong side of the filter....so fit dry and in my case 200 pumps to bleed pre and engine filters.....hope this helps.
Click to expand...

I rember the conversation we had at the time when you popped into SC.
I don't think we were about to do our fuel filters then.
It turned out really easy - not many hand pumps needed at all.
I think the key was that the fuel tanks were full to the brim which helped enormously.

They definately needed bleeding though.
 
DavidJ said:
the contamination in fuel is microscopic and you are likely to introduce contaminants from your can into the wrong side of the filter....so fit dry and in my case 200 pumps to bleed pre and engine filters.....hope this helps.
Click to expand...

Hmm, an interesting point.

In my case the filters I was thinking of were the off-engine pre-filters, so there's still the final filter on the engine to trap anything that does get in. Perhaps I should be more careful when changing the engine filter - although since the pre-filters catch most stuff it's rare that the engine one needs changing at all.

Pete
 
DAKA said:
waste of time, dont do it.

As to professionals I know of one that just uses T-Cut , quick wipe over of the filter with a rag in case anyone has invisible marked it and 'change oil' ticked on the service sheet leaving time to rummage around to see if there is anything worth steeling :eek:

Useless piece of carp didnt even get that right, as he turned it to T-cut it he forgot to tighten it up afterwards .
Click to expand...

DAKA, If you had/have that information on the Low Life, I do hope you reported him to the authorities....... or gave him swimming lessons.

I hate thieves with a passion.

Tom
 
Hurricane said:
I rember the conversation we had at the time when you popped into SC.
I don't think we were about to do our fuel filters then.
It turned out really easy - not many hand pumps needed at all.
I think the key was that the fuel tanks were full to the brim which helped enormously.

They definately needed bleeding though.
Click to expand...
Good point about full tanks I hadn't thought of that mine were low at the time. We have recently lost a lovely couple from Empuriabrava to the charms of SC. A Fairline called Pandora, give our regards if you see them.
All the best
David & Jan
 
LittleShip said:
DAKA, If you had/have that information on the Low Life, I do hope you reported him to the authorities....... or gave him swimming lessons.

I hate thieves with a passion.

Tom
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Early stages, it will be reported on the forum in due course.
He (his Business) has already featured previously on the forum at least once ;)
 
DavidJ said:
Hi
Drained the oil in my KAD43's yesterday and replacing the filters and filling with oil today. I usually fill the new filters before fitting but it does add to the general bother, messiness and probability of spills of the operation.....is this really necessary? I wonder what the professionals do?
Click to expand...

I do, as far as is possible anyway given my oil filters are on their side when mounted.

Whilst I agree it can add to the mess, I minimise this by only part filling them, giving me valuable time to align and get the first turn on before any oil drips out.

I wouldn't worry about what "professionals" do. Given that they're in it to make a living, they're out to get the job done as quickly as possible, so I doubt very much whether many will do this. They don't have to suffer the longer term consequences, and in fact probably benefit from them.

For those who question "why bother?" the reason is simple. It's well known that the most wear takes place on an engine when it's first started up and before the engine has oil pressure. Therefore pre-filling the filter reduces the time taken to get oil pressure, reducing wear and prolonging engine life.

That said, I'm not aware of any engine that has failed prematurely or significantly before its time because of not prefilling. There probably isn't much documented evidence either way.

All I can say is, there is a point, and it definitely makes sense to minimise time taken to achieve oil pressure. For anyone who knows this, and cares, they'll pre-fill. Those that don't care, won't
 
Engine oil

If you're using the time accepted method of warming up the engine (to make it easier to extract the old oil), then all surfaces will be covered with oil and the issue of wear is not relevant (??)

Fuel oil

I have found that changing the filters in two stages helps:-
change the engine mounted filter first and if your system has the primary filter above the engine, open the fuel cock and let the fuel fill the filter by gravity (open the bleed screw).
Then change the primary filter.
Start the engine and use up the fuel in the engine filter. Open the bleed screw and wait five minutes, close it and start the engine again.

There's a bit of coughing - engine running roughly - but it quickly goes away.

My primer lever is useless so I have to do the job as above.
 
Trundlebug said:
I wouldn't worry about what "professionals" do. Given that they're in it to make a living, they're out to get the job done as quickly as possible, so I doubt very much whether many will do this. They don't have to suffer the longer term consequences, and in fact probably benefit from them.
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That's just nonsense. It would take 10 seconds to fill a filter, so it has nothing to do with time. Most modern engines have the filters on the side, or inverted, so it's an even bigger waste of time.

During the course of two years, which is a common oil change interval on modern cars, the engine will be started maybe 1500-2000 times, so do you really think the once it's started after a service is really going to have any measurable impact on an engines life ?

I don't think we'll be getting much benefit from not pre-filling oil filters.
 
PaulGooch said:
That's just nonsense. It would take 10 seconds to fill a filter, so it has nothing to do with time. Most modern engines have the filters on the side, or inverted, so it's an even bigger waste of time.

During the course of two years, which is a common oil change interval on modern cars, the engine will be started maybe 1500-2000 times, so do you really think the once it's started after a service is really going to have any measurable impact on an engines life ?
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Realistically it does take a few minutes to fill a filter. You pour in the oil until it's full, then wait for it to soak in to the element inside. Often need to refill several times before it's properly soaked in and stays full and it takes maybe 5 minutes per filter. It's fiddly, and slow, and therefore quite frankly I can't see a professional ever doing it.

As regards starting afterwards, I take your point about number of starts but bear in mind it can take up to 30-45 seconds for oil pressure to build up after an oil change, whereas it takes less than 1-2 in each normal start. That could be much more significant than you think. E.g. Equivalent to the wear of 30 normal starts.
 
Trundlebug said:
Realistically it does take a few minutes to fill a filter. You pour in the oil until it's full, then wait for it to soak in to the element inside. Often need to refill several times before it's properly soaked in and stays full and it takes maybe 5 minutes per filter. It's fiddly, and slow, and therefore quite frankly I can't see a professional ever doing it.

As regards starting afterwards, I take your point about number of starts but bear in mind it can take up to 30-45 seconds for oil pressure to build up after an oil change, whereas it takes less than 1-2 in each normal start. That could be much more significant than you think. E.g. Equivalent to the wear of 30 normal starts.
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OK, let's go with the "Equivalent to the wear of 30 normal starts". Modern cars have two year service intervals, in that time a car will be started 1500 to 2000 times, let's be generous and say 1500. A service, without pre-filling the filter imposes the same wear as 30 of those starts. So, 50 services imposes the same wear as starting the car normally between two services (two years). So you'd need to service the car for 100 years to impose the same wear as starting it normally for 2 years.

Either way, all the bearing surfaces are still coated with oil, it's not like you're starting it with dry surfaces. If there was any merit at all in pre-filling filters manufacturers would insist on it, now we have 100,000 mile warranties etc.

If you are happy to waste your time doing it, that's your choice. But, please don't say that professionals fail to do it because of the time it takes and that they don't care. Some don't care, some of us do.
 
I do it at work because there's no way of turning the generators over on the starter to pump through, fill up and build oil pressure without either a) setting the alarms off and placing the bridge team in a state of distress and consternation or b)dismantling the alarm system and poking screwdrivers into the control cabinet. It is a bit slow pouring 5 litres of cold oil into a filter, but it's preferable to the generator whizzing up to 1800 rpm with no oil pressure for the first couple of seconds(they are preheated so it's not as cruel as it sounds).

If your oil filter isn't upright I wouldn't bother; just crank it over with the engine stop activated.

I don't fill fuel filters because there's either gravity feed or a hand pump for bleeding.
 
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