Primer for CAV Filter Head

gavin400

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I'm changing my CAV296 fuel filter assembly to a Delphi 496a (spin on), and I also want to add a hand primer bulb to the head
ASAP offer 2 options - a primer bulb that fits the inlet side and one that fits the outlet side (cant tell the difference in the catalogue) - anyone any idea as to which one is required?

Many thanks


Gavin
 
I'm changing my CAV296 fuel filter assembly to a Delphi 496a (spin on), and I also want to add a hand primer bulb to the head
ASAP offer 2 options - a primer bulb that fits the inlet side and one that fits the outlet side (cant tell the difference in the catalogue) - anyone any idea as to which one is required?

You might consider buying a filter head with a built-in primer, such as this one for £28 - https://www.ssldieselparts.co.uk/single-filter-assembly-with-primer-screw-filter-p-274.html
 
Consider changing your CAV filter for a top loader 1000 times easier to change the filter.

What is difficult about changing a CAV filter?

I am no engineer, but I don't ever recall it being a problem on any of the 20 or so boats I've owned over the last thirty years or so.

Turn off the fuel tap, place a tupperware box under the filter, undo one bolt, swap old cartridge for new, hold in place, refit bolt, open tap, bleed, check for leaks, tidy up.

I can imagine other filters might be a bit quicker/ easier, but have real difficulty with the "1000 times" claim.
 
I'm changing my CAV296 fuel filter assembly to a Delphi 496a (spin on), and I also want to add a hand primer bulb to the head
ASAP offer 2 options - a primer bulb that fits the inlet side and one that fits the outlet side (cant tell the difference in the catalogue) - anyone any idea as to which one is required?

Many thanks


Gavin

CAV was bought by Lucas. Lucas merged with and changed its name to Delphi.
 
What is difficult about changing a CAV filter?I am no engineer, but I don't ever recall it being a problem on any of the 20 or so boats I've owned over the last thirty years or so.Turn off the fuel tap, place a tupperware box under the filter, undo one bolt, swap old cartridge for new, hold in place, refit bolt, open tap, bleed, check for leaks, tidy up.I can imagine other filters might be a bit quicker/ easier, but have real difficulty with the "1000 times" claim.
Old Method1) Clear the aft cabin, remove the boards, lay sideways, extend hands above your head while holding spanner.2) Undo, big bolt, remove glass bowl, remove filter, remove all O rings by touch alone. 3) Un-contort body, wriggle out of position remove old stuff from rear cabin. Clean stuff and assemble bowel, filter and O Rings. Re-enter the rear cabin (that now has that lovely smell of diesel), lay on side, re-contort body, fiddle about to find spanner, re assemble bowel and filter stack and marry up to fitting. Grow a third arm to hold the stack in place while your two natural arms are fiddling with bolt and spanner. All done by touch alone4) Bolt is now home, un-contort body and turn on fuel. Notice that the second O ring has not sealed and you have a leak. Repeat item 3.5) Clean up and reassemble rear cabin. I am not a fan of the smell of fuel in the morning. New methodOpen engine compartment, remove four bolts from the new Separ primary filter, remove lid, remove filter, replace filter, replace lid tighten four bolts open bleeding screw, close bleeding screw, check for leaks. Close engine compartment. And I can see everything that is going on. The old method needs two cups of tea to go cold, and there is an optional vomit stage if you are in a seaway. The new method needs one cup of tea and it's still hot by the time you have completed it.
 
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Old Method1) Clear the aft cabin, remove the boards, lay sideways, extend hands above your head while holding spanner.2) Undo, big bolt, remove glass bowl, remove filter, remove all O rings by touch alone. 3) Un-contort body, wriggle out of position remove old stuff from rear cabin. Clean stuff and assemble bowel, filter and O Rings. Re-enter the rear cabin (that now has that lovely smell of diesel), lay on side, re-contort body, fiddle about to find spanner, re assemble bowel and filter stack and marry up to fitting. Grow a third arm to hold the stack in place while your two natural arms are fiddling with bolt and spanner. All done by touch alone4) Bolt is now home, un-contort body and turn on fuel. Notice that the second O ring has not sealed and you have a leak. Repeat item 3.5) Clean up and reassemble rear cabin. I am not a fan of the smell of fuel in the morning. New methodOpen engine compartment, remove four bolts from the new Separ primary filter, remove lid, remove filter, replace filter, replace lid tighten four bolts open bleeding screw, close bleeding screw, check for leaks. Close engine compartment. And I can see everything that is going on. The old method needs two cups of tea to go cold, and there is an optional vomit stage if you are in a seaway. The new method needs one cup of tea and it's still hot by the time you have completed it.

So you reckon removing 4 bolts and a lid, changing the filter, replacing the lid and refitting 4 bolts is 1000 times easier than simply twisting one filter off and spinning a new one on?

Oh, and these Separ filters you're suggesting. Aren't they about £400 to buy, and aren't replacement filter elements about £30 each? The spin-on 496 filters the OP was thinking about are £6 each, plus £28 for the filter head.
 
So you reckon removing 4 bolts and a lid, changing the filter, replacing the lid and refitting 4 bolts is 1000 times easier than simply twisting one filter off and spinning a new one on?Oh, and these Separ filters you're suggesting. Aren't they about £400 to buy, and aren't replacement filter elements about £30 each? The spin-on 496 filters the OP was thinking about are £6 each, plus £28 for the filter head.
For me yes. I really don't enjoy the work needed to change the old filter.
 
Ye gods, that's the thick end of £200. I will stick with CAV types thanks. I had one of those pump CAV types on a Peugeot 309 so in the spirit of PBO a trip down the scrappy might be a cheaper option.
 
Thanks for that, Sandy.

I guess if I had to clean and assemble my bowel, I might be tempted to change, too.

Seriously, though, the problems you describe are mostly related to filter location, rather than type of filter, aren't they?
 
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Thanks for that, Sandy.I guess if I had to clean and assemble my bowel, I might be tempted to change, too.Seriously, though, the problems you describe are mostly related to filter location, rather than type of filter, aren't they?
Very true, but the top filler was added as long term I am planning voyages where the quality of the fuel is not as good as we expect in the UK, so having the convenience of a 10 min filter change is significant.
 
The cav filter is easy to change once you can get at the thing, that is the problem. On my boat the cav was tucked up near the fuel tank in a small locker just large enough to get one arm in. I moved it to a more accessible location at the front of the fuel tank. It takes me all of ten mins maximum to change and bleed the thing.
Edit. Sorry just seen the above post.
 
+1 for these, my first boat had one and it was easy and quick to change. The priming pump is excellent, much better than using an outboard priming pump which strike me as a bodge.
 
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