CAV filter question

Crinan12 said:
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 ?
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Either air is getting in or there is a blockage some where.

I had that when my primary filter got blocked due to muck left in my tank on build
 
Crinan12 said:
So the fuel hose attaches to the top of the filter ? Surely it goes out one of the ports on the side ?
Anyone else have one of these filters that can help ?
It's an sfa11 and takes a screw on delphi 496 filter
Thanks
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The top connection is for bleeding. Two in and two out. Mine (fitted to a BNC 1.5) has one in connection fitted with a non-return valve which takes the excess pressure from the injection pump.
 
Well I've been at it since 8am and no further forward
The longest I have had it running was a few minutes but it always dies
I seem to be able to use the built in primer on the filter to pump fuel through to the bleed screw on the engine itself
The wee lever on the engine to bleed fuel doesn't seem to do much
I've had everything apart and back together a few times
I'm covered in diesel

One thing I was wondering- could the lift pump be knackered ? I'm wondering if the fuel I'm priming to the injectors gets it going but then it dies because the fuel pump is goosed?
 
Probably clutching at straws here but where the filter screws to the filter head there is a plastic washer thing and then a rubber washer as well. Should the plastic thing be there? I wondered if it was stopping the filter sealing properly and letting air in?
 

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Crinan12 said:
Probably clutching at straws here but where the filter screws to the filter head there is a plastic washer thing and then a rubber washer as well. Should the plastic thing be there? I wondered if it was stopping the filter sealing properly and letting air in?
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The plastic retainer is to hold the small seal in the centre of the filter.
 
Thanks Paul I had tried it with and without that
Should I now bleed the injectors?
I'm not sure how to do it but I'll give it a go if it might help
Thanks
 
Crinan12 said:
Thanks Paul I had tried it with and without that
Should I now bleed the injectors?
I'm not sure how to do it but I'll give it a go if it might help
Thanks
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If it ran for a minute before stopping, probably no need to bleed the injectors. However, to bleed the injectors, you loosen the nuts holding the metal pipes to the top of the injectors by about 1/2-1 turn. Then you crank the engine until clear fuel squirts out (some rag will minimise the worst of the mess). Then re-tighten them. If you have an assistant to help you, get them to crank the engine, then you tighten then nuts up when fuel squirts out. Don't crank the engine excessively, as you could damage the starter. You should also turn the seacock off while cranking for longer than usual periods of time.

It does sound more like you are drawing air in somewhere though. Check all connections.
 
Cheers Paul I've disconnected and reconnected everything quite a few times and it all seems fine
I've resorted to reading the manual it says in the troubleshooting to check for a blocked injector or a blocked fuel lift pump or a broken fuel injection pump spring

I think i need to get an engineer to fix it. I'll look into the injector things thou
Thanks
 
Crinan12 said:
Cheers Paul I've disconnected and reconnected everything quite a few times and it all seems fine
I've resorted to reading the manual it says in the troubleshooting to check for a blocked injector or a blocked fuel lift pump or a broken fuel injection pump spring

I think i need to get an engineer to fix it. I'll look into the injector things thou
Thanks
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You could try replacing the pipe from the filter to the engine with clear fuel pipe, you'll be able to see if there are any air bubbles developing.
 
Crinan12 said:
I'm planning on moving the filter to in front of the engine so I will need to change the hoses. At the moment it's behind the engine
Maybe it is time to shell out for one of these fancy racor things I've been reading about. Just object to the £200!
Is there a way of knowing if it is a genuine CAV?
Thanks
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Just replace it with a really good Racor 500 system - by far the best - takes up a little more room but a joy to change filters -quick, no mess and seal easily!
 
Okay I am going to come clean

I have just discovered that I connected the diesel return pipe and the supply pipe the wrong way round
 
PaulRainbow said:
Oh well, probably not the first one to do that. All running OK now then ?
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It ran for a good 15-20 minutes before dying
I'm getting air in because there are bubbles coming out from the bleed screw at the primary filter when I prime it
Back to the yard tomorrow to investigate
But I feel I'm getting there, slowly
Thanks for the help
 
Crinan12 said:
It ran for a good 15-20 minutes before dying
I'm getting air in because there are bubbles coming out from the bleed screw at the primary filter when I prime it
Back to the yard tomorrow to investigate
But I feel I'm getting there, slowly
Thanks for the help
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I admire your persistance mate.
Worst fuel problem I ever had was similar symptoms when stuck in a rolly anchorage with an onshore wind picking up to 20kn. And the anchor had dragged 40m while we were ashore getting groceties.
I have two initial filters in parallel so I can switch over between them. The problem was the same when I switched over so must be downstream of these filters, right? Maybe the on-engine fine filter, the lift pump, the high pressure pump or any of the dozen joints in that part of the system.
After four hours of bleeding and swearing and stressing out, I found that the glass bowl of one filter had a crack, allowing air in, and the other was half blocked by a fine dust. Two faults simultaneously, same symptom.
Keep in mind the possibility that its more than one part of the fuel system at fault. Unusual, but possible.
Luckily I had a spare filter bowl on board and plenty of replacement filters. Hammering out of that anchorage was a sweet moment!
 
That's bad luck !
My mistake was not taking a minute to step back and have a look at the basics. I was so fixated about details I didn't notice I had connected the bloody pipes up the wrong way round !
 
We’ll be down tomorrow to provide the moral support.

I can confirm to all that C12 had a big grin when he discovered and rectified the problem. :ROFLMAO:
 
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