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83958 Major - 2018 - Hoses

Discussion in 'Boxers/TR/M' started by vincenzo, Feb 4, 2018.

  1. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    #1 vincenzo, Feb 4, 2018
    Last edited: Feb 4, 2018
    Finally picking up the major that was not completed in 2016.... Long story, mea culpa.

    ANYWAY:
    One big PIA has been the hoses. As such, it seems that a thread on ‘just’ hoses is warranted.

    Let’s start with the coolant hoses:

    Scuderia Rampante hoses were used on the coolant system. Great hoses.... they are a no BS purchase - they fit and of high quality. SR has done their homework!

    SR provides perforated Breeze clamps with their hose. Not my favorite.

    Instead, I chose to use OEM style Norma clamps with embossed ribs for the tightening screw. They have a rolled edge and in my mind are ‘easier’ on the soft silicon hoses. Rather than the standard OEM materials, I upgraded to the W4 (304 SS) clamps. The OEM material seems to be a zinc coated carbon steel.

    Here is my source:
    https://www.caphardwaresupply.com/collections/frontpage/products/norma-torro-hose-clamps-9mm-wide-w4-stainless

    Note the yellow QC confirmation paint.


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  2. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    Here is the OEM hose in its original position, but sliced open.

    Note that the factory clamps were NOT necessarily positioned in between the aluminum tube’s raised ribs. A bit surprising to me.... the designer’s did their job, but the guy’s on the floor didn’t.


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  3. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    MAINTENANCE ITEM:
    On the al tubes, there are air bleed ports. The steel bleed plug fits into an aluminum boss - perfect for dissimilar metal corrosion. The steel plugs are NLA.

    There is a very small amount of coolant trapped between the tapered seal and the plug’s threads. The corrosion inhibitor is rapidly consumed in this confined space and corrosion ensues.

    Simple solution.... at each oil change, bleed off just a few drops of coolant through the fitting. The ‘fresh’ coolant will bring new corrosion inhibitor with it. Use anti-seize on the threads (only) to minimize any corrosion here. Do not overtighten!


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  4. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    #4 vincenzo, Feb 4, 2018
    Last edited: Feb 4, 2018
    Here is the aluminum boss.... the corrosion was carefully cleaned out with a brush and a bit of scraping.

    These plugs & their aluminum bosses require care!


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  5. turbo-joe

    turbo-joe F1 Veteran

    Apr 6, 2008
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    romano schwabel
    this is not the fault of those on the floor, it is the problem/mistake of the designers: the hose itself is too long
    same happened to me when I ordered new silicone hoses. I meassured the old ones and send my order. but i meassured before I removed them, and when I wanted to install the new ones I have seen that 2 are too long. but better too long than to short :)
     
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  6. turbo-joe

    turbo-joe F1 Veteran

    Apr 6, 2008
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    romano schwabel
    those steel plugs are normal brake bleeding plugs/bleeder, nothing special
     
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  7. Motob

    Motob Formula 3
    Professional Ferrari Technician

    Nov 11, 2003
    2,162
    Berkeley, CA
    Full Name:
    Brian Brown
    Always replace the fuel return hoses from the injection to the fuel tanks. These hoses turn to rock and will crack/leak possibly causing an engine fire. I always carefully cut them lengthwise and peel them away from the fittings instead of trying to twist and pull them off of the fittings. If you break the aluminum tubes off of the fuel tanks, you will be in a world of hurt. Trying to find someone that can weld the nipple back on after you remove the tanks from the car is next to impossible.
    You can replace all small fuel tank breather hoses while you have the engine out, as they are all the same size.
     
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  8. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    It has been said before (Motob) but it is worth repeating...

    It is CRITICAL that you not put ANY stress on the fuel tank nipples. I likely spent at least 10 minutes carefully cutting the hose from each nipple. This aluminum is soooooo soft, a slip of the exacto knife will scar the nipple. I’d bet it would cut all the way through the nipple almost as easily as the old hard hose is cut!

    The return line is a location where I deviate from the F-Car OEM style hose - a 3/8” US made HP fuel injection hose works well here.

    More to come...
     
  9. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    Oooopppsss...
    I spoke off the top of my head in error. My memory ain’t so young anymore!

    The fuel line for the FI return is actually a 5/16” and NOT a 3/8”.

    Cheers,
    Vincenzo
     
  10. turbo-joe

    turbo-joe F1 Veteran

    Apr 6, 2008
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    romano schwabel
    5/16? not exactly, this is only 7.93 mm but F is a european car, so no inch sizes. it is a 8 mm hose, so about 1/10 mm larger diameter
    but agree: be very carefully when removing from the fuel tanks. when I do this job I always use a fine cutter to split the old hose, but sometimes they are so hard it is really a very difficult job not to damage the small aluminum connectors at the fuel tanks
     
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  11. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    #11 vincenzo, Feb 5, 2018
    Last edited: Feb 5, 2018
    The DN 8 hose has a 9mm ID +/-0.5. For the vent hoses, I use Cohline 2122-0800 (DN 8).

    The DN 6 hose at 7.5mm ID is definately too small.... it would require too much force to slide over these nipples.

    The SAE 3/8” at 9.5mm ID is too sloppy.

    The SAE 5/16” is 7.94mm ID.... just right!

    The 5/16” hose requires a modestly firm but NOT a forceful pressure to slide over the nipple (with a thin smear of petroleum jelly). Personally, if I was choosing the hose by ‘feel’ - I’d go with the 5/16” every time. The only reason I use Cohline hose is to match the OEM external braid as a ‘look alike’. That is ok for a vent.... but for a fuel return line (always flowing) I always go with the SAE internally braided hose.

    From a technical standpoint the externally braided hoses are junk... but they look nice!

    Here in the US the SAE hose is a fraction of the Cohline $$$$ and is available at any parts store.

    Here is a cut sheet from the Cohline catalog:


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  12. turbo-joe

    turbo-joe F1 Veteran

    Apr 6, 2008
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    romano schwabel
    why is in this list you posted the DN 6 ( NW = Nutzweite , so diameter ) 2 times, one time with 7 mm and 1 time with 7,5 mm
    also the d ( inside diameter ) varries plus/ minus 0,5 mm.
    do you have a list also with inch sizes? would be good to know what size then the 5/16 hose has?
    because I wonder about that the DN 8 has an ID from 9 mm. have not know this :(
    where you found this list? can not see it on the cohline homepage
    have a look here: http://www.farnell.com/datasheets/1868542.pdf or here:http://www.haagner.com/kataloge/schlauch/oelbenzinschlauch.pdf
    same DIN 73379 Typ B, inside diameter 8 mm, outside 13 mm, working pressure 10 bar and 15 bar, so same DIN but different dimensions?
     
  13. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    The nominal SAE hose size is the ID in 1/16” increments.... the nominal 5/16” hose has a 5/16” ID. In hydraulic hoses, it would be called a ‘dash’ 5 hose (written as -5). Conversely, in the US, a tube is measured on the OD. This means a -5 hose fits on a 5/16” tube. Super easy.

    SAE hose OD will vary with the type, manufacturer and pressure rating.

    Here is the Cohline catalog for hose and fittings:
    http://www.cohline-uk.net/AFHC_2013_Teil_21.pdf

    I am unsure of the size differences you noted in the various EU catalogs.... it can all be pretty confusing at times (especially when I try to read German!). Perhaps a British standard verses a DIN???
     
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  14. turbo-joe

    turbo-joe F1 Veteran

    Apr 6, 2008
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    romano schwabel
    it is all so complicated and confusing :(
    but as I see it a hose with 7,5 mm to 8,2 mm with a good clamp will always work fine. but I prefer the larger diameter because of removing in the future again.
    has anybody meassured the outside diameter from the fuel tank nipples? so not where it is a liitle thicker, there where it is "normal"?
     
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  15. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    Sorry for the slow reply...

    The fuel tank nipples’ OD ranges from 0.312” to 0.322” - call it 8mm (0.315”). This is behind the upset (raised) portion of the nipple.

    Cheers,
    Vincenzo
     
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  16. turbo-joe

    turbo-joe F1 Veteran

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    romano schwabel
    thank you vincenzo
     
  17. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
  18. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    Note the use of convoluted tubing to protect the water & fuel vent hoses as they pass thru areas that may chaff.

    The alternator hose was protected at the clamp locations with Tesa electrical tape. This tape is used to make wiring looms and is made from cloth with ‘just a bit’ of adhesive.
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  19. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    #19 vincenzo, Mar 5, 2018
    Last edited: Mar 5, 2018
    After a lot of permutations on hose - big changes were made. The cloth exterior hose was rejected for the fuel system.

    Two sizes are needed:
    15mm for the tank overflow return lines
    8mm for the roll over vents
    8mm for the FI return line

    The only OEM style hose available is in 14mm and 17mm. The 14mm seemed too stretched when slid over the fitting and the 17mm was too loose as is shown here:

    [ame]http://youtube.com/watch?v=D4LBN1xWIt8[/ame]
     
  20. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    Here is the 14mm Cohline fuel hose and the 5/8” (15.9mm) hose side by side. A 15mm hose would be ideal - but I’ve been unable to find it!

    The modern 5/8” hose is the closest fit available... it should be perfectly fine in this application.


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  21. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
  22. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
  23. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
  24. ago car nut

    ago car nut F1 Rookie
    Silver Subscribed

    Aug 29, 2008
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    David A.
    You could use the blue silicone hose for the water. Not original but supposedly superior.
     
  25. vincenzo

    vincenzo F1 Rookie

    Nov 2, 2003
    2,737
    Agreed -

    But one thing I’ve learned about hoses..... they are a PIA to get right. I’ve spent a lot of TIME & money getting these things ‘right’ for size and suitability. The Scuderia hoses are great quality and fit - they are a ‘no issues’ purchase. They should ALWAYS be the first choice hose purchase.

    Buying hose, getting close, then buying something else, then something else again is a waste of $ and LOTS of time screwing around. Waiting on UPS just to get something not quite right SUCKS. Can’t say enough good things about SRI hose... except that they need to make MORE sizes and lengths available... like for example, add tank vent hose to their fuel pump hose package!

    Example: the 55mm filler neck hose...
    I’ve had well known ‘professional’ shops tell me to use 2-1/4”... bought it, got it, rejected it. SEARCHED and found 2”... bought it, got it, rejected it. After MUCH more searching, found a SINGLE manufacturer that makes a 2-1/8” fuel hose... you guessed it...bought it, got it, rejected it. Finally landed on the SRI hose. It is the ONLY hose I could find that is ACTUALLY 55mm. Great quality, no brainer and it FITS.

    SRI rocks!

    Cheers,
    Vincenzo
    PS: SRI water hoses are silicon based, but WITH cloth abraision covers.
     
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