[T3] Stupid question #395 Oil change time?

[Jim Adney]

On 27 Jun 2019 at 22:42, Soren Jacobsen wrote:

> I hate to admit it, but I've avoided using modern fuel hose in my
> engine compartments because I simply can't stand the look of it and
> the engine compartment is the most aesthetically important area of the
> car to me.  I've also been troubled by the "oh, just use some Good
> Quality quarter inch hose and clamp the hell out of it" mindset.  I'd
> much rather have something that fits to begin with.  I replace braided
> fuel hose every couple years, though; doesn't cost much or take very
> much effort, and under this maintenance schedule I've never taken off
> a hose that looked scary.  Perhaps I'm lucky, or the local fuels are
> relatively benign.  I've heard of people having rotten braided lines
> as soon as a year after installation.

Most of you don't remember what the FI engines looked like when they were 
new. Yes, the hoses had exposed braid, but that was covered by some grey 
vinyl sleeving that made the exposed braid invisible except at the very ends, 
where the single-loop Oetiker hose clamps were. There was very little braid 
visible and no screw type hose clamps of any kind.

I'd LOVE to find a source for grey vinyl sleeving, because I suspect that it 
provided one more layer of heat shielding that kept the gas from boiling 
during the heat soak after shutdown. I actually have a roll of vinyl sleeving 
that I bought years ago from VW as replacement, but that came in black 
instead of grey. Maybe it would work the same, or maybe the black color 
would absorb heat faster than grey. Who knows what this looks like in IR 
(Infra Red?) I haven't tried it. Just lazy, I guess.

> Anyway!  With that confession out of the way, I recently stumbled upon
> some properly-sized (for the earlier cars that I'm most interested in)
> fuel hose.  I ordered some, but it hasn't yet arrived.  It's pretty
> expensive, but I figure if it lasts a decade (under the car where no
> one can see it -- I won't be installing this in any engine
> compartments, because ew bare rubber!) who cares about the cost: 
> 
> http://www.volksbolts.com/faq/fuelhose.htm

This is a really interesting web page. They've done a great job of condensing 
the SAE hose specs down to the essential stuff. It looks like R6 or R7 would 
be fine, but R9 would be better and R14 would be excellent. Too bad no one 
bothered to proof read the page, as there are a number of typos, and they 
substitued permitivity for permeability, which is completely wrong.

> There's also this braided stuff, which I haven't bought yet but probably will in the near future:
> 
> https://www.belmetric.com/multifuel-hoseethanol-approved-c-14_662/rhm5braid-flennor-multifuel-hose-5mm-braided-p-9852.html

You'd have to buy the 5 mm stuff to fit on your 6 mm fittings, which is a 20% 
stretch, whereas 10% stretch is the max recommended. Our original 7 mm FI 
hoses tended to fail where they were stretched over 8 mm tubing, so VW 
changed to 7.5 mm hose. I now use 8 mm hose, which I can get away with 
because of the 8.? bulges in most of the fittings. There are a few straight 8 
mm fittings, but only 2 that are under pressure. Those take extra care (full 
circle clamps) to seal reliably.

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Jim Adney, jadney at vwtype3.org
Madison, Wisconsin, USA
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