Air in Fuel lines

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TRANSPORTER
1.8 8v
Posts: 22
Joined: Tue Dec 10, 2019 11:32 am

Air in Fuel lines

Post by TRANSPORTER »

Hi Guys, first post so introduction first, running a 406 2.1 diesel, on the 8B engine. She's an R plate so 98 if memory serves me right. Runs like a dream and give me 53+ mpg so not complaining one bit. I carry out as much work on her as I can ( use of ramps etc at work ) and keep her going as best I can.
My problem at the moment ( after I've just changed lower wish bone N/S and auxiliary belt, 2 1/2 hours!!!!! just for the belt ) is air in the fuel lines.

Now I've done some research as this has been an ongoing problem for a little while now for myself and others, So far I have changed the primer bulb but had to use the old one way valve and other fittings as the fittings that came with it were different ( straight as opposed to right angled ) I then changed as many of the pipe clips for new jubilee clips, greased all pipes when refitting to help create an air tight seal.

Yesterday after more air bubbles were seen in the fuel lines I got the clingfilm out and wrapped the primer bulb and all pipe joins to try and see if that would show me where the leak was coming from. To no avail as bubbles were still in fuel lines.
I thought I had narrowed it down to the actual fuel filter housing as the bubbles were for a little while only coming from there to the FIP and not from the primer bulb to the fuel filter. I have a new fuel filter and a base gasket O ring ready to install just to take them out of the equation ( both genuine Peugeot ). But after a little while bubbles were coming from the primer bulb direction as well.

When I switch the engine off small bubbles can be seen leaving the FIP going towards the fuel filter but not actually getting there and also tiny bubbles from the primer bulb area also travel towards the filter but don't actually get there. I have also bled the fuel system as per haynes manual twice now.

Also since fitting the new primer bulb I noticed the other day that it is being sucked in like there is a vacuum in the system, I had not noticed this before but every commute to work now and its almost flat when I stop. I have opened the fuel cap to allow it to vent to see if that will release it but it doesn't. It will however over a period of approx 10 sec re-inflate itself to normal shape once I have turned the engine off.

I'm now looking at by passing all the pipes under the bonnet and connecting two new clear pipes direct from the connection on the bulk head (white tang quick release ) to the primer then straight to the filter housing then from there straight to the FIP. This will hopefully tell me if if the old pipes had any problems.
The main question I have is the quick release connector ( white tang ) what size would I need? I have measured the pipe and its just over 10mm (10.78mm on my vernier ) I have tried Peugeot but they no longer sell them, and my local scrap dealers although they have them fitted to cars they would not allow me to remove them due to environmental issues. I don't want to waste money buying the incorrect size as I want to get the pipe system made up in one go before fitting it and testing.

Apologies for the long first post but any help greatly appreciated, thanks in advance.
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Doggy
Mod with a 2.2 HDi, De-Fapped!
Posts: 10710
Joined: Mon Oct 13, 2008 11:49 pm
Location: Northants

Re: Air in Fuel lines

Post by Doggy »

Hi and welcome aboard. 8)

Sounds like it would be worth checking out the in-tank strainer. It's a while ago but I seem to remember similar issues on another 2.1.
All the pics were hosted on Photobucket so can't give you a link
2002 HDi 2.2 Exec Estate, (2008-12) (wonderful)
2003 HDi 2.2 6-speed Exec Estate (2012-19) (also a gem)
2009 Citroen C5 2.0 HDi VTR+ Estate (godawful heap)
2008 BMW E91 330i touring (great fun - murdered by a reversing SUV)
2007 BMW E91 325i touring (slower smoother quieter)
TRANSPORTER
1.8 8v
Posts: 22
Joined: Tue Dec 10, 2019 11:32 am

Re: Air in Fuel lines

Post by TRANSPORTER »

Interesting, I guess that is a rear seat out job and through an inspection hatch is it? just trying to think why I would be getting air because of this, could you enlighten me please.
TRANSPORTER
1.8 8v
Posts: 22
Joined: Tue Dec 10, 2019 11:32 am

Re: Air in Fuel lines

Post by TRANSPORTER »

Ok just to close this one as much a so can, I checked the strainer in the tank and it was proper clogged up, I suppose it’s never been looked at since it was installed in 1997, I had to pop a rivet on the cover to gain access.
The large amount of bubbles have now gone so I guess this was the cause, I have started another thread in regard to “other bubbles” so hopefully I can put that issue to bed.
Cheers for I do and help so far
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