Fuel filter positioning

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seaangler23

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I'm replacing a fuel filter assembly ( standard 296 filter with glass bowl) but there is nowhere ideal for it to be so it's is bolted to the engine bay wall around the height of the top of the engine. The problem with it's current set up is that the filter sits above height of the top of the tank so if your changing the filter it's a pain to bleed without sucking it through, not great if it's to be done at sea. There is a hand primer on the engine lift pump but it doesn't have to go to pull it through from the tank. How do people get around this? Searches for in line primers just bring up bulbs for outboard fuel lines which I'm not keen on as they seem to deteriorate and a potential leak which isn't an option. There are filter assembly's with primer pumps built in like these
http://pages.ebay.com/link/?nav=item.view&alt=web&id=281517943396
But im looking for 1/2" unf fitting to save changing the set up and can't find one with these connections.
Also the fuel tap is at the filter in the bay and nothing at the tank outlet, id of thought one at the tank would be preferred in case of a fire? Even if the fuel will run back to the tank.
 
Can't help with the inline thingy, I'm afraid.

Our filter assembly (CAV) was very poorly accessible behind the engine and only just reachable from the bottom of the cockpit locker on the other side of the bilge. (I can't imagine what the installer was thinking.) We had it moved to in front of the engine (and behind the removable companionway steps) - it couldn't really be much more accessible. It's also gravity fed, so great. Not all boats will have sufficient space there, though.

It doesn''t have to go inside the engine compartment, though. If you have somewhere suitable adjacent to the engine compartment (a locker, or the heads, perhaps) you could just run the fuel lines through the bulkhead.
 
It's fairly accessible where it is, easy enough to get to but the problem lies with bleeding it because wherever it goes I won't have gravity feed, I did look at moving it but I'd have the same problem. The good thing is that it's easy to bleed from the filter to lift pump and onwards once you can get fuel to the filter
 
Had similar problems years ago when I fitted two new filters and my mistake was I fitted them too high up, after many trials and heartache I solved the problem by mounting the filters lower so they are gravity fed.

In the downpipe from the tanks to the filters I fitted a open/close valve for changing the filters.

I also found by moving the filters slightly closer to the lift pump I can now also pull diesel through, one thought is (sorry if you already do) when you refill the filter do you open the bleed valve at the top?

I also fitted a change over valve so I can use either tank very quickly if required

This year I changed both glass filter bowls to spin on type but still have drian in the bottom http://www.ebay.co.uk/itm/SFA11-FIL...460?pt=LH_DefaultDomain_3&hash=item4ae86f6944

Hope this might help

View attachment 54415 View attachment 54416 View attachment 54418
 
Nice set up, I can't get the filter lower than the tank unfortunately, the tank sits below a cockpit locker so pretty much as low as it can be, if I open the bleed screw on the filter it would let the fuel run back to the tank, really not an ideal set up. The filter is close to the lift pump but it doesn't have the pull to get it uphill from the tank to the filter. I have seen set ups with an electric lift pump after the primary filter so they can be mounted low but this seems ott when it's only needed for bleeding
 
Last edited:
seaangler23 said:
Nice set up, I can't get the filter lower than the tank unfortunately, the tank sits below a cockpit locker so pretty much as low as it can be, if I open the bleed screw on the filter it would let the fuel run back to the tank, really not an ideal set up. The filter is close to the lift pump but it doesn't have the pull to get it uphill from the tank to the filter. I have seen set ups with an electric lift pump after the primary filter so they can be mounted low but this seems ott when it's only needed for bleeding
Click to expand...

Yes that was my problem as my tanks are also just below the cockpit sole, I spent months moving the filters into different positions but finally I got some bent steel brackets from B & Q and bolted them to the bottom support of the tanks to mount them lower, my filters are not in the best accessible place but they solved the problem and even though I like the glass bowl type which I had before I have not regretted changing over to the spin on type.

Mike
 
seaangler23 said:
Searches for in line primers just bring up bulbs for outboard fuel lines which I'm not keen on as they seem to deteriorate and a potential leak which isn't an option.
Click to expand...

The one in my car has been in service for 21 years !
 
seaangler23 said:
I'm replacing a fuel filter assembly ( standard 296 filter with glass bowl) but there is nowhere ideal for it to be so it's is bolted to the engine bay wall around the height of the top of the engine. The problem with it's current set up is that the filter sits above height of the top of the tank so if your changing the filter it's a pain to bleed without sucking it through, not great if it's to be done at sea. There is a hand primer on the engine lift pump but it doesn't have to go to pull it through from the tank. How do people get around this? Searches for in line primers just bring up bulbs for outboard fuel lines which I'm not keen on as they seem to deteriorate and a potential leak which isn't an option. There are filter assembly's with primer pumps built in like these
http://pages.ebay.com/link/?nav=item.view&alt=web&id=281517943396
But im looking for 1/2" unf fitting to save changing the set up and can't find one with these connections.
Also the fuel tap is at the filter in the bay and nothing at the tank outlet, id of thought one at the tank would be preferred in case of a fire? Even if the fuel will run back to the tank.
Click to expand...

I too have the pre-filter high (about level with the top of the tank and top of engine) with no problem with bleeding after a filter change. Surely the hand priming lever on the fuel pump just replicates the action of the engine on the pump. Therefore, if the engine can work the pump to suck the fuel from the tank, so should you be able to by hand???

Colin. Www.solocoastalsailing.co.uk
 
Plum said:
Therefore, if the engine can work the pump to suck the fuel from the tank, so should you be able to by hand???
Click to expand...

My hand doesn't move at 2000rpm, though :)

I have an outboard-style bulb just after the tank which lets me push fuel through the system and fill up a new filter in a few seconds.

Pete
 
Great I like the one you can bolt to the cab filter but if a rubber one will be alright that's easier, many see if I can get a good quality one not Chinese ebay crap
 
We fitted a spin on filter head with a built in primer pump as fitted to some cars. They are not expensive. You can prime effectively when that are mounted above the engine. The spin on filter in so much better that the old CAV type. You can change a filter in a minute, prime the system and be on your way again in no time. We used to pay about £3 per filter from a motor factors for the filters so used to buy about 10 at a time. I think I paid about £26 for the last one I bought of EBay. Here is an example
http://pages.ebay.com/link/?nav=item.view&alt=web&id=181826074457&globalID=EBAY-GB
 
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