Daverw
Well-Known Member
I think they mean out of the centre of the filter, blow though each port and see which one is connected to the centre, then that’s the outlet
CAV filter question
- Thread starter Crinan12
- Start date
Crinan12
Well-Known Member
Does this look right? I can't get it to bleed. But I'm not sure if the small or big bolt on the top of the filter is the bleed screw or if the hoses are connected the right way round so I'm just guessing. Can't really find any literature on the internet about how these things work. I'll disconnect it all and see if I can figure it out.
Thanks
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PaulRainbow
Well-Known Member
The pipes are connected like this ;
NEW Diesel Filter Primer Top - Universal Lucas 14-1.5 thread
The small screw is likely to be a bleed screw, as it's fitted to one of the outlets. I'd remove the pipe from the fuel pump, stick it in a bottle and operate the hand pump on top of the filter with both crews fully tightened. In future, when you change the filter, fill it with diesel before you screw it on, then just give it a few pumps until the hand pump gets hard to press.
Crinan12
Well-Known Member
Paul see when you say outlet do you mean the pipe that goes from the filter to the engine ?
Also when I try what you suggest is the idea that diesel will come out of the pipe into the bottle ?
I've given up for today as getting dark but going back 1st thing tomorrow to see if I can figure it out.
If anyone has a manual for one of these could you let me know please
I did have a look online but there doesn't seem to be much information like that available.
Thanks
Daverw
Well-Known Member
Is the large black knob to push to prime as it looks like it’s on a large diaphragm, also not sure you will find a user manual as such as it would be part of a larger system manual as in a car or like.
Crinan12
Well-Known Member
Yeah dave the black one is to prime it
Cheers
Cheers
LittleSister
Well-Known Member
I am guessing here -
1) Black button on top is a priming pump
2) The top (right hand) side is the output
3) Small screw in top of far right hand end (blanked off spare outlet) is a bleed screw, as Paul Rainbow says
4) Hose near right should be output to engine
5) Lower (left hand) side is intake
6) Far left hose should be inlet from tank
7) Near left is a blanked off spare inlet.
I suggest -
Loosen the small screw at the far right. Pump with the black knob. Does diesel eventually come out?
If not, try swapping each hose to the other hose's position.
Note that most filter heads I've seen have arrows, or written 'in' and 'out', marked on the body to indicate what is inlet and what is outlet . Maybe someone saved a few pence in the manufacture of yours.
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Crinan12
Well-Known Member
Hi yeah I think that is right what you are saying
I pumped the priming knob for ages and nothing happened but I didn't realise I had to pour diesel into the filter first to fill it up.
I was sore and covered in diesel and it was getting dark, but going back first thing in morning to try again
Thanks
I pumped the priming knob for ages and nothing happened but I didn't realise I had to pour diesel into the filter first to fill it up.
I was sore and covered in diesel and it was getting dark, but going back first thing in morning to try again
Thanks
PaulRainbow
Well-Known Member
You don't have to fill it with diesel, but it saves a million pumps with the priming knob.
It's really super simple, the inlet connection goes to the tank and the outlet goes to the engine, the diagram i posted should show which is which, looks like you have it connected correctly. If so, take the pipe off that goes to the engine (at the engine end, which will be the fuel pump), stick it in a bottle and operate the primer pump. When diesel pumps out, with no air, reconnect the pipe. Do this with the bleed screw closed. If no fueol comes out, you can always double check the pipes are on the right way round by putting your finger over the disconnected pipe and see if it sucks or blows when you operate the primer pump, it should obviously blow.
Crinan12
Well-Known Member
Cheers paul
I'm going to the boat shortly so I'll give it a try
From reading other posts on here I believe I may need to bleed the injectors as well
I'm going to the boat shortly so I'll give it a try
From reading other posts on here I believe I may need to bleed the injectors as well
PilotWolf
Well-Known Member
Crinan12
Well-Known Member
I must admit I've just used jubilee clips
PilotWolf
Well-Known Member
if there’s room then put another one each side then. They are know to fail - I ve had them break.
W
PaulRainbow
Well-Known Member
So has pretty much everyone else. Along with all of the plumping and heads hoses on the boat too. Nothing wrong with decent quality, 100% stainless fuel line clips. Rather than worn drive clips, for fuel lines, i prefer this style ; ABA Stainless Steel Mini Fuel Hose Clips (just an example, lots of suppliers available)
PilotWolf
Well-Known Member
Thats the problem though. Most aren’t 100% stainless, most people including myself buy them from Halfords or similar.
its also easy to over tighten them too. This can distort the hose and/or the barb. As well as putting the pressure on increasing the likelyhood of failure.
W.
rogerthebodger
Well-Known Member
This is the old standard CAV filter head giving the flow directions.
As far as I remember CAV never did one which included a primer pump. I could be wrong.
I would blank the 2 on one side and fit a pipe to one of the others. Then fill a jar with water and put the pipe into the water and pump the primer pump. If bubbles come out or the end of the pipe ,the pipe is connected to the outlet. If water is sucked in then this is the inlet. You can then repeat with the other 2 connectors.
This also my help.
As far as I remember CAV never did one which included a primer pump. I could be wrong.
I would blank the 2 on one side and fit a pipe to one of the others. Then fill a jar with water and put the pipe into the water and pump the primer pump. If bubbles come out or the end of the pipe ,the pipe is connected to the outlet. If water is sucked in then this is the inlet. You can then repeat with the other 2 connectors.
This also my help.
Crinan12
Well-Known Member
Paul I did what you tried
When I push the black knob on the filter fuel pumps out of the end of the pipe going to the engine. When I connect it up and press the priming lever on the engine fuel comes out of the bleed screw.
However the engine won't start. It did for a few seconds but died. Now it just turns over.
Is my next step to bleed the injectors?
I've replaced my tank, the hoses and both filters.
Thanks
Crinan12
Well-Known Member
This is how mine is set upThis is the old standard CAV filter head giving the flow directions.
As far as I remember CAV never did one which included a primer pump. I could be wrong.
I would blank the 2 on one side and fit a pipe to one of the others. Then fill a jar with water and put the pipe into the water and pump the primer pump. If bubbles come out or the end of the pipe ,the pipe is connected to the outlet. If water is sucked in then this is the inlet. You can then repeat with the other 2 connectors.
This also my help.
Red is the one coming from the fuel tank
Green is going to the engine
My understanding is that there are 2 ports for fuel in and 2 for fuel out and you can use what ever suits best to plumb it in
Thanks
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Crinan12
Well-Known Member
Got engine started
Ran fine for a minute and then died
Primed again and it started and ran fine again for a minute and died. Repeated this a few times.
Does this mean air is getting in somewhere ?
Ran fine for a minute and then died
Primed again and it started and ran fine again for a minute and died. Repeated this a few times.
Does this mean air is getting in somewhere ?