296 fuel filter and bowl under

[ianc1200]

I hope somebody can give guidance. I'm attempting to service my Beta 20 but haven't started well. The secondary 296 filter shown in photo below has been on and off multiple times yesterday and today. I'm convinced I've got all the O rings bedded correctly, having removed the old. The glass bowl doesn't fill with diesel, and when I open the bleed bolt diesel comes out, after about 20 seconds, but clearly the filter and bowl isn't full. Any suggestions what I'm doing wrong?

 

[Laysula]

Bin it and fit a Racor 500 type.Far far better and easier to use than the CAV type.

 

[PCUK]

Have checked to ensure that the old top seal came off with the filter canister. If it hasn't and you fit a new seal so there are two in place then it won't seal.

 

[simonfraser]

did it work properly before you changed it ?

 

[Sandy]

Keel haul the individual who thought fitting a filter there was a good idea.

As @Laysula suggests fit a Racor 500 (or copy) and life will be much less stressful.

 

[ianc1200]

Have checked to ensure that the old top seal came off with the filter canister. If it hasn't and you fit a new seal so there are two in place then it won't seal.

Definitely removed old.

did it work properly before you changed it ?

Yes. Put old one back on without any change, the glass bowl does not fill up.

Thanks for the replies though.

Just been studying CAV leaflet on how these work - a friend has suggested a pump to "suck through" the filter which might be next step.

Would love to change to a Racor type (which I have on my motorboat) but that's for another day.

 

[ianc1200]

Keel haul the individual who thought fitting a filter there was a good idea.

As @Laysula suggests fit a Racor 500 (or copy) and life will be much less stressful.

Wholeheartedly agree. The return pipe is across the top of the bleed valve. When I had the engine installed in 2015/16 I asked for the same Racor filter as on my motorboat but the engineer said what was there was fine. Will be changed this winter.

 

[B27]

The bleed screw is on the inlet side.
Try turning the 1/4 turn valve off and opening the bleed screw..

Then close the bleed screw, open the 1/4 turn, and go for a cup of tea.

It may take a minute or two for the fuel to soak the filter element and reach the bowl, and for the air to come up through the filter.
I suspect your gen-u-ine Delphi element is quite fine!
I used to fill mine with a syringe.

The bowl is 'after' the filter element.

I assume from the position of your filter, it's below tank level?
So the fuel tends to head straight for the bleed screw?
So you may need to let the top of the filter fill with diesel, wait for it to soak through and the air to come to he top,...
and repeat...

I've changed to a cheap Katsu spin-on filter, with a 'tractor' gauze pre-filter and a priming bulb.

 

[Sandy]

Wholeheartedly agree. The return pipe is across the top of the bleed valve. When I had the engine installed in 2015/16 I asked for the same Racor filter as on my motorboat but the engineer said what was there was fine. Will be changed this winter.

If you go for one of the Chinese copies they only have one in port and one out port! If you have to turn the unit so that the flow is in the correct direction you will need some very thin walled sockets. Don't ask how I know.

 

[38mess]

I have one of these filters. They can be fiddly, also the two larger O rings are slightly different sizes and you need to fit them correctly. Once fitted I suck fuel through with an outboard motor bulb. Seems to work ok for me.

 

[rogerthebodger]

I always spin the filter and glass bowl to ensure the O ring and the flter are seated correctly in the groove and lips

 

[ianc1200]

Many tganks for the replies - come home and will try again tomorrow.

 

[NorthUp]

Have you taken the plastic cover off the top of the new filter? Compare the new with the old filter

 

[ianc1200]

No cover on old or new, but like the thinking - it's got to be something simple and stupid on my part. Did even think I had it upside down until I checked a couple of YouTube videos.

 

[PetiteFleur]

I changed to the spin on Filter (and so have 2 friends) - much easier and never leaks. Disadvantage of not having a glass bowl, but never a problem for me. Always use road diesel with MR16 additive. With the previous CAV filter, as PCUK says, check you don't have 2 'O' rings in the upper part. The CAV is a PITA in my opinion, especially it it's in an awkward position.

 

[ianc1200]

Thanks for all the replies. The simple answer was it was an airlock. Went armed wirh two handpumps to suck the diesel through, but it wasn't needed. Simply took pipe from the 296 filter off at the lift pump, and the bowl filled. My pontoon friends also say throw it away and install a Racor, secondly several of them have put a good quality Quicksilver squeezy hand pump in the fuel lines.

 

[ChromeDome]

Are you familiar with diesel engine fuel supply?

Without exception, there must be diesel and only diesel in the entire supply line. Neither the feed pump nor the injection pump can drive the air out.

Therefore, as air will enter when you open the system, you need to bleed the system by opening it at the filter base and pump manually or let gravity fill it until diesel without air bubbles comes out, close the bleed screw and continue to the far end (loosen the nut on the pipe on the injectors one by one) and pump the fuel pump lever until diesel comes out without air bubbles.

Since you've put in a new empty element, you need to pump quite a lot. You can alleviate this by pre-filling the filter before fitting it.

Tip: A very efficient means of sucking up fuel spillage is disposable diapers! And they don't even need to be a major brand

 

[B27]

Are you familiar with diesel engine fuel supply?

Without exception, there must be diesel and only diesel in the entire supply line. Neither the feed pump nor the injection pump can drive the air out.
...

That isn't entirely true, the lift pump should pump air quite happily, and many injection pumps will cope with at least very small quantities of air.
More so once the engine is already running.

 

[ChromeDome]

To be specific re. the engine in question:

From the Operators manual

 

[Boater Sam]

Are you familiar with diesel engine fuel supply?

Without exception, there must be diesel and only diesel in the entire supply line. Neither the feed pump nor the injection pump can drive the air out.

Therefore, as air will enter when you open the system, you need to bleed the system by opening it at the filter base and pump manually or let gravity fill it until diesel without air bubbles comes out, close the bleed screw and continue to the far end (loosen the nut on the pipe on the injectors one by one) and pump the fuel pump lever until diesel comes out without air bubbles.

Since you've put in a new empty element, you need to pump quite a lot. You can alleviate this by pre-filling the filter before fitting it.

Tip: A very efficient means of sucking up fuel spillage is disposable diapers! And they don't even need to be a major brand

How do you prefill a 296 filter and bottom bowl, I think it is not possible.