F-Hose delete

2.7 V6 30v biturbo - 251bhp
2.7 V6 30v biturbo - 261bhp
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tdiquattro
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Post by tdiquattro » Thu Aug 30, 2007 3:16 pm

How-to..

Parts required....

- 078 133 784 BG ..... Front hose £11
- 044 127 563 A ........ Metal T-piece £4
- 06A 103 221 BK ........ Rear hose £8
- A couple of short lengths of 8mm ID thick walled hose
- Small jubilee clips 10mm? 6
- medium jubilee clips 14mm? 4

1) remove Y-pipe, drivers side DV for access, f-hose and bleed valve (this is the fitting on the lower connection to the f-hose).

2) remove the old front hose and reducer that connected to the F-hose and replace with the new front hose direct to the manifold where the f-hose used to be.

2) OK then, no going back after this - you need to cut the long spider hose, the one that runs from the back to the bottom of the F-hose under the inlet manifold. It is hard plastic so be careful not to crack it. To cut it remove the lowest spider hose connection to the back of the manifold and the two upper ones, then you can pull the spider back enough to work on the f-hose leg of it.
It needs to be cut with a knife to leave enough of the smooth non-crinkly part to push the bleed valve you removed in step 1) back onto it (say 35mm) see pic..

[img]modules/pnCPG/Coppermine/albums/userpics/10567/rs246_norm_fhose%20delete3.JPG[/img]

Push the bleed valve on, then the new rear s-shaped hose and route the rear hose as in the pics. The bleed valve ends up down below and roughly facing the way the old spider hose went.

3) Remove the old connection to the N249 and use the new t-piece and sections of 8mm ID hose to make the connection to the N249, rear of the manifold and new rear hose as in the pics.

4) Tighten all new jubilee clips and replace y-pipe and DV.

That's it done, no more F-hose for about £25 and an hours work. :)

Cheers,
Nigel.
Nige'

2000 silver S4 Saloon

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paul20v
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samco f hose

Post by paul20v » Sun Sep 02, 2007 1:05 am

hi were can i get a samco f hose
i think i will fit one as a cautious measure
thanks

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tdiquattro
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Post by tdiquattro » Sun Sep 23, 2007 12:09 pm

In case anyone is interested pics of the new hoses for the front and rear.....

Front from RS4,
[img]modules/pnCPG/Coppermine/albums/userpics/10567/rs246_norm_Resize%20of%20IMG_1231.JPG[/img]

rear fron 1.8T,
[img]modules/pnCPG/Coppermine/albums/userpics/10567/rs246_norm_Resize%20of%20IMG_1232.JPG[/img]
Nige'

2000 silver S4 Saloon

MarkB
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Post by MarkB » Fri Oct 12, 2007 10:54 am

Been thinking about doing this mod and I've seen it come up recently on the rolling road meet thread.

My worry with doing it is the BPV/N249 connection is alot smaller than the connection the f-pipe uses normally. The PLV valve connection is much larger, why not tee into that?
Mark

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Post by MarkB » Fri Oct 12, 2007 11:29 am

MarkB wrote:Been thinking about doing this mod and I've seen it come up recently on the rolling road meet thread.

My worry with doing it is the BPV/N249 connection is alot smaller than the connection the f-pipe uses normally. The PLV valve connection is much larger, why not tee into that?
Edit that last bit. I mean the large pipe off the inlet manifold that I assume goes to the servo.
Mark

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tdiquattro
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Post by tdiquattro » Thu Dec 06, 2007 6:07 pm

Sorry Mark, missed your post on this, must have been away...

Yep sounds like a good idea, the hose I connected into is 8mm just because I had the parts to do it and the 1.8T hose was a good fit.

I don't see why you cant use the brake servo hose, just need to find the parts to do it so that the hose internal diameters match up.

I have the 2001.5 manifold now, so I am looking at adapting this mod to fit that when I get time!
Nige'

2000 silver S4 Saloon

MarkB
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Post by MarkB » Thu Dec 06, 2007 7:12 pm

Thanks for the reply... eventually ;)
Mark

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daybar
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Post by daybar » Thu Dec 06, 2007 10:17 pm

I have recently done the F hose delete, greatly encouraged by tdiquattro's excellent how to. :thumbs: Several hundred miles later, all seems fine and I'll do a careful check at the thousand mile mark.

Problems:-

1. Usual aggro with one time clips, reinstalling Y pipe and reconnecting MAF hose. :?
2. Small bore silicon control/pressure pipes connected to the N75 valve run at the rear of the IM and use brittle Y connectors. There are two connectors and I managed to break both by accident. Part no 078 133 381 B and cost pence but no real substitute at Halfords etc, so best get a couple in advance.

No pressure leaks, but I'm a bit concerned that the connection to the cut back spider hose may be a weak point because the cut off spider hose end is plain rather than ribbed, so the hose clip is relying only on compression to hold it all together. If it comes apart, it would be the same as an F hose failure.

The bore of the one way valve in the system is not much greater than the N249 connector in the inlet manifold so perhaps MarkB's concerns will not be borne out in practice. Certainly, there was no significant build up of carbon/gunge in the old pipes but you don't want the new ones to get bunged up at a pinch point and I'll be keeping an eye on it.

I got a spare spider hose, just in case, but didn't damage the old one so saved myself the hassle of fitting the new one. I sawed off the redundant part of the spider hose in situ and this meant I could remove the F hose/one way valve assembly in one piece, which looked a lot easier than trying to disassemble it and a lot less stressful on the rest of the spider hose.

So, many thanks for the write up, tdiquattro - perhaps a candidate for the "How to" sticky?
Silver S4 Avant July 99 "semi" facelift, stock except for MRC custom remap, 710Ns, diy short shift, after run mod, retro fit cruise control, DTS, H+R arbs, n249 delete and F hose delete. Oh dear, this is getting addictive!

MarkB
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Post by MarkB » Thu Dec 06, 2007 10:27 pm

daybar wrote:So, many thanks for the write up, tdiquattro - perhaps a candidate for the "How to" sticky?
Agreed, but I think it should be linked to from the HowTo and Modifications sticky to be neater...
Mark

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rikrose
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Post by rikrose » Fri Dec 07, 2007 11:54 am

Can anyone confirm whether this can be done without pulling the engine?
Goodwood green RS4, previously owned by jeffw

MarkB
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Post by MarkB » Fri Dec 07, 2007 11:58 am

rikrose wrote:Can anyone confirm whether this can be done without pulling the engine?
Yes it can be done without an engine pull
Mark

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daybar
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Post by daybar » Fri Dec 07, 2007 3:06 pm

"Yes it can be done without an engine pull" - no way would I have attempted it if an engine pull had been needed :D

The only dismantling needed is as per the write up at the top of page 3 of this thread.
Silver S4 Avant July 99 "semi" facelift, stock except for MRC custom remap, 710Ns, diy short shift, after run mod, retro fit cruise control, DTS, H+R arbs, n249 delete and F hose delete. Oh dear, this is getting addictive!

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rikrose
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Post by rikrose » Fri Dec 07, 2007 7:43 pm

Interesting... possible one for the future then, when poeple have discovered 2the right pipes to use", and what to watch out for.
Goodwood green RS4, previously owned by jeffw

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tdiquattro
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Post by tdiquattro » Fri Dec 07, 2007 8:31 pm

daybar wrote:
No pressure leaks, but I'm a bit concerned that the connection to the cut back spider hose may be a weak point because the cut off spider hose end is plain rather than ribbed, so the hose clip is relying only on compression to hold it all together. If it comes apart, it would be the same as an F hose failure.
Thanks for the praise, glad to be of service dave :) , I think the cut off connection should be ok as the bleed valve stops the presure getting through, otherwise there would be pressure going back that way through the spider to the y-pipe and engine I assume?, - so there is no pressure there to pop it off I think.

Good point about the plastic t-pieces and about the diameter of the pipe, you are right,

by the way still all fine on mine after a couple of thousand miles in all weathers and conditions.
I think the idea is sound, it is just moving the connection, not really altering the design or valves etc.


Yep sorry Mark, duh, missed your post completely :oops:
Nige'

2000 silver S4 Saloon

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daybar
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Post by daybar » Fri Dec 07, 2007 10:54 pm

"I think the cut off connection should be ok as the bleed valve stops the presure getting through, otherwise there would be pressure going back that way through the spider to the y-pipe and engine I assume?, - so there is no pressure there to pop it off I think."

Yes, you're absolutely right, thanks - I got confused about which way round the parts are in relation to the vacuum/pressure from the inlet manifold :roll:

If I knew how, I'd quote you properly :oops: One thing at a time!
Silver S4 Avant July 99 "semi" facelift, stock except for MRC custom remap, 710Ns, diy short shift, after run mod, retro fit cruise control, DTS, H+R arbs, n249 delete and F hose delete. Oh dear, this is getting addictive!

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