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Re: Fuel expansion tank breather hoses/pipes
Posted: 21 Aug 2013, 11:35
by Arripay
Thanks guys, I understand now. My theory is that the fuel that was spilling was contents of the filler hose after I topped her right up, reckon it must be one of those cross connector pipes, all make sense now,hopefully....
Re: Fuel expansion tank breather hoses/pipes
Posted: 21 Aug 2013, 17:50
by shepster
Quite common Is the grommets (number 6 in diagram) are either missing/perrished etc so when you fill up petrol comes out of there, or possible rot in the 'valley' on top of the tank.
Re: Fuel expansion tank breather hoses/pipes
Posted: 21 Aug 2013, 19:11
by icosahedron
I recently replaced mine again after only two years with clear polyurethane tubing. This clearly shows petrol rushing up the tubes just before the pump kicks out on a full tank. Petrol then remains in the bends below the breather tank.
Re: Fuel expansion tank breather hoses/pipes
Posted: 23 Aug 2013, 08:59
by tonydata
oorwullie wrote:i would also add my personal opinion that these vapour expansion tubes have very little ( like nothing at all ) to do with 2 gallons of fuel spraying on the ground when you fill the tank.........

I could see the fuel coming out of the tubes on to the ground...
Re: Fuel expansion tank breather hoses/pipes
Posted: 23 Aug 2013, 10:13
by oorwullie
i bow humbly to your personal experiences then.
never happened to me or anyone else i know but i never fill up right to the top of the filler tube and my maintenance schedules would be replacing fuel lines etc long before they got to be falling apart.

Re: Fuel expansion tank breather hoses/pipes
Posted: 23 Aug 2013, 13:28
by StuM
On mine, the nearside breather had come out of the tank completely - grommets were fine - I guess it had been knocked at some point. Here's the post about it in my blog:
http://jaspert3.blogspot.co.uk/2011/04/ ... first.html
And the diagram I drew up for mine (though no idea if the sizes are 'standard'):

Re: Fuel expansion tank breather hoses/pipes
Posted: 26 Aug 2013, 17:03
by NeilHarris
Ive a similar problem with my 16JX diesel. The diagrams I have dont show the short length of flexible pipe that appears to come from the expansion tank to the solid pipe. I just need to know what the inside diameter of the flexible pipe is to save me taking it off before buying a new section.
hopefully someone has an idea for the diesel arrangement.
thanks in advance

Re: Fuel expansion tank breather hoses/pipes
Posted: 26 Aug 2013, 17:13
by Oldiebut goodie
All in the Bentley.

Re: Fuel expansion tank breather hoses/pipes
Posted: 26 Aug 2013, 17:40
by NeilHarris
Thats the picture im looking at. Vent line a + b (presume they have not shown them to scale as they are only about 6" long, but no mention of the ID in the manual. I guess I'll take one of them off and measure it. 5.5mm appears to be the concensus
Re: Fuel expansion tank breather hoses/pipes
Posted: 26 Aug 2013, 18:59
by JamesT25
i removed mine completely and just plumbed the holes on top of the tank up. the breather on the petrol fill pipe is more than enough breathing for this country even in our best weather. never had any problems since removal.
just my side for you all!!
Re: Fuel expansion tank breather hoses/pipes
Posted: 26 Aug 2013, 22:22
by RedGus
NeilHarris wrote:Thats the picture im looking at. Vent line a + b (presume they have not shown them to scale as they are only about 6" long, but no mention of the ID in the manual. I guess I'll take one of them off and measure it. 5.5mm appears to be the concensus
Neil, here's what I posted back near the beginning of this thread:
RedGus wrote:
Are you talking about the rigid pipes (2,3 + 4) or the flexible ones (15)? Or both? The rigid ones are just 6mm pipe, so can be remade in copper if they are rusted through.
The flexible hose is just standard 5.5mm ID fuel hose, in short lengths. Both these things are generic parts, like this:
Copper pipe link
Fuel hose link (drag the box to choose size you need)
Re: Fuel expansion tank breather hoses/pipes
Posted: 27 Aug 2013, 19:14
by NeilHarris
Thanks for the replies. My layout appears to be the petrol rather than diesel drawings but without the jubilee clips. Not to worry i've ordered a couple of lengths from the link attached and we'll see if that fixes it.
Re: Fuel expansion tank breather hoses/pipes
Posted: 13 Jul 2014, 19:09
by NeilHarris
Now changed the complete tank as I had a 'bit of an issue' whilst away in Germany with the hoses on the top of the tank.
Take my word for it, that if you've needed to change the pipes to the expansion tanks, then the others are in a similar state.
Not a bad job, apart form draining the tank whilst only having it jacked up on stands, and a two person jobs to fish all the pipes into the right place when putting it back in again.
I can confirm that you only need about 1m of 5.5mm hose for all the top of tank stuff and some 7.5mm for the inlet and outlet at the rear of the tank. Maybe only 12" for this part.