Running the fuel filter dry before changing filters

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Babylon

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Before changing the primary fuel filter, would it not be a good idea to close the fuel-cock first and run the filter bowl dry (or almost dry if you've got a glass bowl) before spinning the thing open? Thinking about reducing the mess of fuel spills.

What are the downsides?

The bowl and hoses probably contain half a litre, so the process would involve up to half an hour's running.

Running the thing dry would introduce air into the system, but one's always got to bleed the system after changing filters anyway.
 
Babylon said:
Before changing the primary fuel filter, would it not be a good idea to close the fuel-cock first and run the filter bowl dry (or almost dry if you've got a glass bowl) before spinning the thing open? Thinking about reducing the mess of fuel spills.

What are the downsides?

The bowl and hoses probably contain half a litre, so the process would involve up to half an hour's running.

Running the thing dry would introduce air into the system, but one's always got to bleed the system after changing filters anyway.
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you would produce blockage & vacuum, the fuel in the filter so the fuel wouldnt flow.
use a plastic container under the filter to collect any spillage
 
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If you shut the fuel cock all you do is draw a vacuum in the fuel system, stop the engine and make it harder to remove the filter bowl. You will not be introducing air into the bowl unless you have a leak.

Try doing what most of us do and use a tough plastic bag or container to surround the filter as it is unscrewed.

Fill the filter with fresh fuel before you fit it and you will reduce the amount of bleeding required.
 
You can't 'suck' dry any filter I've seen, as the outlet pipe doesn't go to the bottom of the sludge bowl, it's up at the top.
If you've got a really awkward installation that can't be made better easily, (like me!) cut up a plastic drinks/milk bottle to make a catcher tray and use the water trap drain to clear the entire contents of the filter before dismantling.
 
What they all said - plus top tip picked up from the SeaStart guys - buy yourself one of those little squeezy black bulbs used for outboards. After changing the filter, temporarily disconnect the fuel feed to the engine and stick the bulb in the end of the hose. Pump until fuel comes through thus refilling the filter bowl, damn site faster than trying to tickle the lift pump into doing the same job.
 
RobbieW said:
What they all said - plus top tip picked up from the SeaStart guys - buy yourself one of those little squeezy black bulbs used for outboards. After changing the filter, temporarily disconnect the fuel feed to the engine and stick the bulb in the end of the hose. Pump until fuel comes through thus refilling the filter bowl, damn site faster than trying to tickle the lift pump into doing the same job.
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Yup that is THE best way, we did it and did not have to bleed the engine!!

Peter
 
RobbieW said:
What they all said - plus top tip picked up from the SeaStart guys - buy yourself one of those little squeezy black bulbs used for outboards.
Click to expand...

Maybe I was unfortunate but I did this about two years ago, but I have had 3 in less than 18 months. The first was replaced free of charge, the second lasted about a year, and the third, a slightly different type leaked when first fitted, so I got a refund.

I have now fitted a Hand Primer ½ in Banjo Pump onto the filter inlet. As supplied here www.asap-supplies.com/ for about £8.00. This works first class, but I only fitted it last year, so time will tell.

Other comments I would agree wholeheartedly with. Haven fun George.
 
If you've got the clearance a two litre or quart plastic milk bottle with the bottom cut off (& lid on of course!) used inverted is good for catching the fuel, esp. with the built in handle.
 
While I'm normally very keen on finding a use for something otherwise being discarded, I'm going to strike a dissenting note on the cut up milk bottles etc. ideas. For the grand sum of about 35p Asda will sell you a plastic kitchen measuring jug with a handle and just the right size for catching the filter, bowl, fuel and all. Much easier than jiffy bags, tops of bottles etc. because having caught everything you can then set it down in the cockpit on its flat bottom and sort through all the captured bits methodically. There is even a spout for neatly pouring out the fuel either back into the tank if clean or into your disposal vessel of choice if dirty.
 
Plastic lined jiffy bag works very well. Dump everything into the bag. Remove the bits you want to save and bin the rest.
 
I still use a milk container if I have one spare. It is rectangular instead of circular and so catches more as it is snug against the bulkhead.

I also keep an ASDA cheapo 0.5l measure to hand and decant most of the clear liquid into it through a kitchen tissue stuck inside. Residue in milk container is usually small enough to soak up in a couple of tissues for disposal later.
 
No one's mentioned Racor filters if you want a clean and diesel-free life. No mess with them, and no bleeding in my case. Love 'em.

You pay more, but the first time you have to change the filter you'll think it was worth every penny.
 
oldvarnish said:
No one's mentioned Racor filters if you want a clean and diesel-free life. No mess with them, and no bleeding in my case. Love 'em.

You pay more, but the first time you have to change the filter you'll think it was worth every penny.
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Are they available as retro fit for any engine? (Thornycroft 75hp)
 
GeorgeLlewellin said:
I have now fitted a Hand Primer ½ in Banjo Pump onto the filter inlet. As supplied here www.asap-supplies.com/ for about £8.00. This works first class, but I only fitted it last year, so time will tell.

George.
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I have just fitted three of these in succession and they all stopped sucking after around 12 shots. The first I pulled apart and discovered the valves had rusted. That was probably because of residual water in the system and perhaps a reasonable excuse. The second two just failed to suck any more. They cannot be dismantled without destroying them.

I wondered if dirt had stopped the valves closing properly but they are installed before the filter (as directed) so should cope (otherwise what is the need for a filter?).

Anyone else had such a problem with these or is it just my luck?
 
oldvarnish said:
No one's mentioned Racor filters if you want a clean and diesel-free life. No mess with them, and no bleeding in my case. Love 'em.

You pay more, but the first time you have to change the filter you'll think it was worth every penny.
Click to expand...

I have Racor filters but clearly not in the same mounting as yours as I need the Tesco measuring jug (other brands are available) technique to change the filter :( Any chance of a link to the sort of thing you're on about ?
 
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