the gas bladder: exposed!

[galaxee]

okay now bear with me folks, i just tried to remove that duplicate post and as expected, and following in the trend that has been my hellish experience with trying to do ANYTHING right in the past week... i just dumped all the pics in this thread by deleting that other thread... i don't get it... #$(*%$()&*(*&()$%^*

sigh...

edit: okay, this should fix the issue once and for all. man i really did not want to have to go and re-upload all that crap but here it is. and a good night to all!!!

[tripp]

Galaxee, thanks for taking the time (yer DH too, of course) to show us this. On the one hand, it's really cool. On the other hand, it seems ridiculously complex for a bloody fuel tank.

[aaf709]

I agree with tripp that's pretty complex.

Thanks for the pictures!

[bwilson4web]

Hi,


I have an NHW11 and the filler is on the passenger side. I'm trying to figure out how the filler tube routes from the photos. Also, I'm trying to understand what it takes to replace the tank since the Toyota 2003 maintenance manual just shows the tank, not how to replace it.

Is this tank from an NHW20 or NHW11?
Does the NHW20 have the filler on the driver side?
In figure 1, are we seeing the tank top or bottom?
I noticed two holes on the opposite side of the tank in figure 1, what do they connect to?
Does tank removal require taking out the rear axle?

These are great photos and I'll add a note to the GH Prius FAQ about the overfill risk.

Thanks,
Bob Wilson

[hobbit]

How absolutely excellent. Thanks to you both, you totally rock!
.
So the box of "Toyota seal packaging" wasn't so that DH could put the
thing back together, huh?
.
I've gazed long and hard at the pics of the tank in the NCF and some
other places, wondering more about what's in there and the bladder
characteristics... and the fact that the EVAP system actually pulls
air through the surrounding steel tank and *checks* it, using the A/F
sensor while the engine's running, for any fumes! They really don't
want any gas outside the bladder, even though the rest of the tank is
pretty much sealed up. Here's a cleaned-up rework of one of the
pix from the "university of Toyota" stuff, which I think is now also
available at autoshop101.com:
__ http://techno-fandom.org/~hobbit/pix...00/bladder.jpg
which must be from a NHW11 because it looks a bit different.
.
The bladder seems to have much more shape and rigidity than just a
rubber bag, so there must be times when it has *some* vapor above the
fuel inside it... now, the big question is this: where does the
overfill fuel go, i.e. what path does it take to actually get into
the outer tank? Since the bottom of the bladder and everything-box
are sealed with respect to each other, it's got to be out through
the fresh-air inlet or purge system and back in somehow.
.
By contrast with the fact that this one is sealed up and one must
replace the whole wazoo to repair any of that stuff in the everything-
box, take a look at the "fuel tank R2D2" in
__ http://www.99mpg.com/Workshops/understandingdiagn/
a larger version of which is at
__ http://techno-fandom.org/~hobbit/pix...os/iostank.jpg
and note that the black "jar lid" screw ring around the white piece
is how you get the fuel pump out of an Insight tank [non-bladder,
of course]. Something like this seems to be a much better design
for serviceability, rather than having to replace the entire tank!
There are some places where I look at Honda and Toyota and go "okay,
what the heck was [one of them] thinking?!"
.
Sorry about the somewhat "advertisey" link, but we really are trying
to get independents into these seminars. Mike is a total *monster*
with a welder as you can see, and has done the vast bulk of the work
on these projects.
.
I hope to have a similarly detailed expose' of the inverter up at
some point ...
.
_H*

[Beryl Octet]

<div class='quotetop'>QUOTE(galaxee @ Apr 6 2007, 11:41 PM) [snapback]419197[/snapback]</div>

quick introduction: this was the second bladder that DH has replaced for overfill damage.
[/b]

So, putting too much fuel in causes damage to these? I assume by damage, you mean they start leaking?

[galaxee]

bwilson- this is from a NHW20. the filler is on the driver's side. i'll ask DH tonight if he's pulled a tank from a classic prius. the first pic is the top of the tank, and the two holes you ask about are for a couple of sensors, i forget which ones he said they were. one is the sensor that detects fuel in the space between the bladder and the metal tank.

hobbit- i knew you'd be all about this i'll have to wait for DH to answer all your questions, i'm sure he was expecting a few discussion points from this thread!

beryl- fuel in space between tank and bladder. very, very bad. check out the thread discussing what happened to this car here: http://priuschat.com/index.php?showtopic=30786

[bwilson4web]

<div class='quotetop'>QUOTE(galaxee @ Apr 7 2007, 10:53 AM) [snapback]419365[/snapback]</div>

bwilson- this is from a NHW20. the filler is on the driver's side. i'll ask DH tonight if he's pulled a tank from a classic prius. the first pic is the top of the tank, and the two holes you ask about are for a couple of sensors, i forget which ones he said they were. one is the sensor that detects fuel in the space between the bladder and the metal tank.
. . .
[/b]

Ahhh, I see it now. I've taken out the rear seat of my NHW11 and it rests on top of the gas tank. Knowing which side the filler tube comes down clarifies that first NHW20 tank photo. I still don't know if the tank comes out via the cabin but that would be a sensible approach for the NHW20.

Given what the tank did to the air tool, I feel a lot better about crash-worthiness.

Thanks again, the photos are great. Good luck on the grant. My niece got a three year NSF grant.

Bob Wilson

[Beryl Octet]

<div class='quotetop'>QUOTE(galaxee @ Apr 7 2007, 10:53 AM) [snapback]419365[/snapback]</div>

beryl- fuel in space between tank and bladder. very, very bad. check out the thread discussing what happened to this car here: http://priuschat.com/index.php?showtopic=30786
[/b]

Thanks, I usually don't try to squeeze every last drop in, anyway, just curious.

[Oxo]

<div class='quotetop'>QUOTE(galaxee @ Apr 6 2007, 11:41 PM) [snapback]419197[/snapback]</div>

here are the pictures. it was a hell of a lot of work, and the poor guy now is sitting next to me with an ice pack on his shoulder! enjoy!

[/b]

Very useful and interesting - all 25 pics! I wonder how many hours it took Toyota's people to design it?

Am I wrong in thinking that European models of the Prius do not have a bladder? Is there any easily visible external evidence that a bladder is fitted?