So Im doing the usual winter service jobs - oil, gearbox, fuel filters, anodes, etc, and I run into a problem. After replacement, the primary CAV fuel filter/ water separater won't fill. I try everything, fuel primer, blow return, suck via secondary, but nothing. Check fuel entering top of primary filter housing, obviously fuel on & fuel moving...but it quickly fills breather cap, without entering filter or bowl - huh? I check for air gaps or other pressure in system and nothing I get x4 of the club's brains trust on the job and still no result. I reassemble old filter (which was remarkably clean!) and it immediately fills and after bleeding/ priming secondary filter and injectors with fuel engine starts & works fine. Only explanation is a faulty fuel filter...but i replaced like with like - even used the old rubber seals when checking.

System is a standard type with clear bowl DELPHI 7111-296 filter - Engine is Kabuto/Beta marine BD1005

Any Advice appreciated.

if you definitely had all the right seals in place then i would try another filter...

Hi Bruski, fishmonkey and grich - thanks for advice. Couldn't agree more with the filter 'design' comment. Easy to remove but a bugga to reassemble & bleed (yes my lift pump is approx 2m and vertical of prime filter). I've consulted another mechanic who has suggested it is likely an air pocket in filter assembly/ pressure. Failure can occur in seals (ships, I didn't realise the bowl seal was the larger one!) yet, I can't understand how as: 1-no fuel leaked when assembled, even after I attempted to pre-fill (yes a very messy experience & I'm sure no seal blockage on filter).
So grich it looks like I need a spin on filter - any that you could recommend for 28hp Beta - interested in cost effectiveness here.

I've used those filters for years. They are fine if you have easy access to like in a trawler engine room but hard to assemble laying on your side working across a yachts "engine room". I'm about to toss mine, I'm sure it's a source of an air leak. I'm assured by my mate these are the go. They are not real Racor's but good enough.
http://www.ebay.com.au/itm/Fuel-Filter-Water-Turbine-Diesel-Biodiesel-Separator-500FG-Brand-New/182504779037?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

I've got a similar tale of reliability with the cav type filters, in a great arangment of machines. There can be a difference in seal kits and as Ramona suggest if access if is tight they can be a trial to assemble, if the old filter worked on refit then my guess is that the filter is bodgy. Unless there's a sneaky oring stuck on your old unit that hasn't come with the new kit ?

Ramona said..
I've used those filters for years. They are fine if you have easy access to like in a trawler engine room but hard to assemble laying on your side working across a yachts "engine room". I'm about to toss mine, I'm sure it's a source of an air leak. I'm assured by my mate these are the go. They are not real Racor's but good enough.
http://www.ebay.com.au/itm/Fuel-Filter-Water-Turbine-Diesel-Biodiesel-Separator-500FG-Brand-New/182504779037?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

ok guys i don,t want to get in to fight ,but the 500fg requires a lot fuel flow to make the turbine work they are designed for high flow fuel systems on high power engines so not the ideal filter for replacing the cav filter .they also suffer from over tightening and can leak at the top .also be aware of non return valves in the filter head. i often use a oil evacuation pump to prime a hard system and they will show up a air leak around the filter .most times you can get spin on fuel filter heads from a marine shop just make sure you get a diesel filter to fit, stemco also make good filter sets to suit .if it is mounted to the engine you will need room to remove.remember that you are not filtering lots of fuel so you don,t need a big filter . if your filter is mounted high in the engine room it will be even harder to get the fuel from the tank down to the pump so use the oil evacuation pump to help bleed . while using the pump you can find any blockages or collapsing fuel lines (cheap auto fuel line is for pressure not vacuum not for boats )

grich62 said..

Ramona said..
I've used those filters for years. They are fine if you have easy access to like in a trawler engine room but hard to assemble laying on your side working across a yachts "engine room". I'm about to toss mine, I'm sure it's a source of an air leak. I'm assured by my mate these are the go. They are not real Racor's but good enough.
http://www.ebay.com.au/itm/Fuel-Filter-Water-Turbine-Diesel-Biodiesel-Separator-500FG-Brand-New/182504779037?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m1438.l2649

ok guys i don,t want to get in to fight ,but the 500fg requires a lot fuel flow to make the turbine work they are designed for high flow fuel systems on high power engines so not the ideal filter for replacing the cav filter .they also suffer from over tightening and can leak at the top .also be aware of non return valves in the filter head. i often use a oil evacuation pump to prime a hard system and they will show up a air leak around the filter .most times you can get spin on fuel filter heads from a marine shop just make sure you get a diesel filter to fit, stemco also make good filter sets to suit .if it is mounted to the engine you will need room to remove.remember that you are not filtering lots of fuel so you don,t need a big filter . if your filter is mounted high in the engine room it will be even harder to get the fuel from the tank down to the pump so use the oil evacuation pump to help bleed . while using the pump you can find any blockages or collapsing fuel lines (cheap auto fuel line is for pressure not vacuum not for boats )

Thanks for the heads up on fuel flow and getting the turbine to work. Mate has one on his Perkins so I will have to check that.

thank you seabreezers - so many good ideas here - learning by doing!