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.
Is there a seal on the top of the filter that needs removing before installation?
if you definitely had all the right seals in place then i would try another filter...
these filter set ups are the worst filter ever made,they will leak air into them every time you fit a filter kit.make sure that the 2 large o rings are in the correct spots 1 is slightly larger than the other,the larger one goes on the bowel to filter connection,do not use grease to hold them in place as when you tighten it may slip and leak air also make sure the bolt has a new seal and the top o,ring is in place take the whole filter of and assemble it upside down taking care to mate o,ring seal .there are also 2 different seal kits available 1 has o,rings and 1 has square o,rings ,make sure your kit is exactly the same as what came out.once you are sure it is assembled right vacuum test it for leaks . also if it is fitted before the lift pump it can take a while to bleed all air out,if it is fitted after bleed it at the filter .investing in a spin on filter is my advise as think how hard this is to do in a big sea under stress no eng floating towards some rocks.
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 hate to be the bull in the China shop but I like that exact filter and have used them often! But they are a trick to put together.
Maybe the input / out ports on the top are mixed up?
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 ?
Cant say Ive had any issues using them over the years , you did fill the new filter up with fresh fuel before screwing back on ??
Select to expand quoteConcepcion said..
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.
cav filters and delphy filters are 2 different designs make sure you have the correct designed filter for your brand. looking at the photo it does not look fitted right the bottom o,ring looks set to one side and the top appears in to much is there a o,ring fitted between filter and the housing .you can get small cheap vac pumps from most shops,it was the only way i could start a gen set on a mariatimo that had run out of fuel,its prime pump had no chance of sucking fuel the 5 meters back to the genset
This is the vac tester and catch can I have and use. Vacuum leaks in the fueling system can be hard to find as quite often air will be getting drawn in but no fuel will be leaking out. I have also found that pressurizing the system will sometimes not diagnose the problem.
