Date: Wed, 3 Aug 2016 15:07:19 -0700
Reply-To: Neil N <musomuso@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Neil N <musomuso@GMAIL.COM>
Subject: Re: Bucking/Loss of power on HOT days
In-Reply-To: <9b35f6f6-ceef-3d4d-663a-03a37ea7368f@turbovans.com>
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Thanks for that. I'd wondered about installing a fan. I recall bostig guys
doing something similar for a different purpose (engine bay fan)
OP might find info in that in bostig group or on the samba vanagon forum?
On Wednesday, August 3, 2016, Scott - IMAP <scottdaniel@turbovans.com>
wrote:
> there actually was a an engine compartment fan ..
> fitted to some Datsun 280Z sports cars ...
> aimed at the fuel rail area.
>
> a factory fix just for this issue. a Bit dorky, but works.
>
> On 8/3/2016 1:43 PM, Neil N wrote:
>
> On my '81 with Jetta 2.0, a similar thing happened. The fuel pump has
> always been prone to being noisy ( new at time of swap as was tank etc.)
> but would always get louder on hot days especially if climbing a
> steep grade for any amount of time.
>
> On a trip through a desolate area, with my fuel pump screaming away, I
> pulled over, let engine idle. It sputtered and died. It felt like vapour
> lock. It wouldn't start so I pulled the gas cap and heard a "whoosh" of
> air. With cap off, engine started. On a spare gas cap, I removed a little
> material to help allow tank to pull in ambient air. Not sure if this helped
> but no more stalls. I swapped in a used charcoal canister after that and of
> course reinstalled the other gas cap.
> AKAIK, my fuel pump hasn't been that noisy since.
>
> My swap uses the Jetta charcoal canister purge valve which is
> quickly cycled open closed by the ECU. Does the obd1 Suby swap use a
> similar valve?
>
> At one point I wondered if my different purge valve system pulled more air,
> over a given period of time, than the OEM design. i doubt it though. Even
> if it did, the charcoal filter should vent to atmosphere right?
>
> On my swap the fuel hoses likely pick up heat in engine bay but then I have
> to imagine that the WBX fuel hoses being so close to the engine case, would
> also allow fuel to pick up heat.
> OTOH, I can't recall if the WBX return hose is above the WBX engine.
>
> I'd be curious to see how your Suby swap would work with a fuel tank having
> the 12 mm outlet.
>
> Neil.
>
>
> On Wednesday, August 3, 2016, Richard Koerner <rjkinpb@sbcglobal.net> <javascript:_e(%7B%7D,'cvml','rjkinpb@sbcglobal.net');> wrote:
>
> Am having bucking and loss of power on very hot days.
>
> My van is an 85 2WD (233,000 miles), manual tranny, with a 2.2 Subie
> engine (recent conversion by California Westys in San Diego), .....
>
>
> The symptoms are classic "vapor lock"; yes, unusual with pressurized fuel
> delivery on fuel injected engines, but I've been going through the List
> Archives and there have been cases resembling vapor lock.
> Typically, everything runs fine at freeway speeds in hot conditions; the
> bucking problems start when I pull off freeway and have to contend with
> stoplights and idling and low speed.
>
> This has happened at low elevations but hot (Florida and Laughlin, Nevada)
> and also at high elevations (Gunnison, Colorado) on a warm summer day.
> Problem disappears when van is allowed to cool overnight; starts fine and
> runs fine the next day.....until it gets hot outside and van is moving slow.
>
> Mild whining (not screaming) from fuel pump when this happens. I suspect
> some cavitation and pump damage occurred. Anyway, I've replaced fuel
> pump....
>
>
> Other things I've read about include: gas cap, charcoal cannister, bad
> coil, fuel pressure regulator, bad ignition coil.
>
>
>
> --
> Neil n
>
> Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca> <http://tubaneil.blogspot.ca>
>
> 1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy> <https://picasaweb.google.com/musomuso/New1988Westy>
>
> 1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/> <http://tubaneil.googlepages.com/>
>
> Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay> <http://tinyurl.com/khalbay>
>
>
>
--
Neil n
Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>
Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>
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