New diesel fuel hose to CAV filter size of hose tails?

[Captain Crisp]

Hi - I'm renewing the fuel line from tank to my CAV filter. Please advise:
A) what type/size of fuel line? (10hp engine)
B) what thread size of hose tails will fit this type of CAV?
Many thanks!
Crisp

 

[PaulRainbow]

CAV housings can be 1/2" UNF or metric, yours look pretty old, so likely to be UNF

Hose would usually be 8mm, but best to measure to be sure.

 

[ChromeDome]

Agreed. When replacing it would seem easy cut out a bit (away from the end to avoid the expansion) for measuring.
Same with barbs (if they need replacing?).

 

[PaulRainbow]

While you are at it, why not make your life easier and fit a spin on filter conversion ?

For instance: Spin On Fuel Filter Conversion Kit (CAV Replacement)

 

[Captain Crisp]

Agreed. When replacing it would seem easy cut out a bit (away from the end to avoid the expansion) for measuring.
Same with barbs (if they need replacing?).

The previous set up was nylon pvc tube with a compression olive. So no barbs. I'd like to install a proper fire-resistant hose hence the need for barbs.
Thanks
Crisp

 

[rogerthebodger]

Tis is the type of fitting you could use

CAV Lucas Delphi filter pipe adapter 1/2" UNF to 8mm - Diesel Injection Pumps

Fuel hoze

https://www.ebay.co.uk/sch/i.html?_...MI0ou58rD4gwMV2o5QBh1jTA2GEAAYAiAAEgIJ1_D_BwE

 

[PaulRainbow]

Tis is the type of fitting you could use

CAV Lucas Delphi filter pipe adapter 1/2" UNF to 8mm - Diesel Injection Pumps

That type will need a washer Roger and rely on making a seal on the face of the housing.

This one seals inside the housing, as the original pipe and olive would have: 1/2" - 20 UNF CAV FILTER HOUSING HOSE CONNECTOR 8MM STRAIGHT JOINT

Also available with a 90 degree bend: 1/2" - 20 UNF CAV FILTER HOUSING HOSE CONNECTOR 8MM 90 DEGREE ELBOW

 

[PabloPicasso]

While you are at it, why not make your life easier and fit a spin on filter conversion ?

For instance: Spin On Fuel Filter Conversion Kit (CAV Replacement)

For £45quid you could replace it with a racor knock off. I even added a fuel tap to make changing the filter a simple easy job.

 

[PaulRainbow]

The Racor copies are now at silly prices, £16.15 !!!

500FG/FH Diesel Marine Trucks Fuel Filter Oil Water Separator & Bolt Ring UK | eBay

 

[rogerthebodger]

The Racor copies are now at silly prices, £16.15 !!!

500FG/FH Diesel Marine Trucks Fuel Filter Oil Water Separator & Bolt Ring UK | eBay

Just goes to show how over priced the OEM supplier

 

[LittleSister]

While you are at it, why not make your life easier and fit a spin on filter conversion ?

For instance: Spin On Fuel Filter Conversion Kit (CAV Replacement)

If making that change, should one also add a water separator (presumably between the tank and the new fuel filter)? The CAV, for all its faults had an integral one.

 

[rogerthebodger]

I fitted one of these to help prevent sediment blocking my primary CAV filter

 

[B27]

I fitted one of these to help prevent sediment blocking my primary CAV filter

Me too.
It gives a view of what comes out of the tank before it's been filtered, and might stop big lumps of stuff from getting into the valves of the primer bulb.

So far, boringly clean!

It was quite cheap, but you need another pair of hosetails and clips.


I don't think these things replace a proper agglomerator/water separator like a CAV, the only filtration is a plastic mesh.

 

[Captain Crisp]

The thing is, after 4 years, I've finally mastered changing my CAV filters... Feel strangely bonded to the b@gger.

 

[LittleSister]

The thing is, after 4 years, I've finally mastered changing my CAV filters... Feel strangely bonded to the b@gger.

Yes, they're quite OK with a bit of practice, but only if you've got -
decent frontal access at a convenient height;
space and/or surfaces underneath that facilitate catching/cleaning up after the inevitable diesel spillage; and
the replacement filters that you bought come (as they rarely do) with all three replacement seals.

 

[PabloPicasso]

Yes, they're quite OK with a bit of practice

No they're not. They are a bloomin' abomination.

Try balancing that pile of jenger at 3am underway in choppy water without regurgitating your dinner.

For under 20quid changing to the drop in type is a no brainer.

Do it now. You'll thank me one day, sure you will, you will, you will...

 

[LittleSister]

No they're not. They are a bloomin' abomination.

Try balancing that pile of jenger at 3am underway in choppy water without regurgitating your dinner.

For under 20quid changing to the drop in type is a no brainer.

Do it now. You'll thank me one day, sure you will, you will, you will...

I actually largely agree with you, and have said much the same as you, though with far stronger language, when I have been wrestling with the blessed things in boats. (Maybe I should have added calm seas and plenty of time and patience to my list of caveats?) They are probably alright on trucks and tractors.

I have actually already bought a Chinese drop-in Racor type as a replacement for my boat's CAV which lacks the benefit of any of my above stated conditions, but am beginning to doubt that I actually have sufficient space for the Racor-alike in my engine compartment. Hence I was pondering earlier in this thread whether a swop to a screw on type (or better still, two with a changeover tap), and if so whether I would then also need a water separator.

 

[PabloPicasso]

I actually largely agree with you, and have said much the same as you, though with far stronger language, when I have been wrestling with the blessed things in boats. (Maybe I should have added calm seas and plenty of time and patience to my list of caveats?) They are probably alright on trucks and tractors.

I have actually already bought a Chinese drop-in Racor type as a replacement for my boat's CAV which lacks the benefit of any of my above stated conditions, but am beginning to doubt that I actually have sufficient space for the Racor-alike in my engine compartment. Hence I was pondering earlier in this thread whether a swop to a screw on type (or better still, two with a changeover tap), and if so whether I would then also need a water separator.

A Facor/Racor-a-like is not that much bigger than a cav. Could you fit it outside the engine bay in an easier to access location?

 

[PaulRainbow]

Yes, they're quite OK with a bit of practice, but only if you've got -
decent frontal access at a convenient height;
space and/or surfaces underneath that facilitate catching/cleaning up after the inevitable diesel spillage; and
the replacement filters that you bought come (as they rarely do) with all three replacement seals.

<pedant mode>

Four seals

</pedant mode>

 

[rogerthebodger]

The only you need to replace all the seals is if the seal is damaged. Seals get damaged by over tightening the center bolt.

It all about being a competent person.

I have changes the Racor and a boat I crewen on some time ago and yes it is easy if you have room as is changing a CAV (IMHO) the main issue is that fuel filters are fitted out or the way in a place that is difficult to access.

To avoid having change a filter in seaway just fit a change over filter arrangement problem solved