Date: Wed, 12 Oct 94 10:02:50 PDT
Sender: Vanagon Mailing List <vanagon@vanagon.com>
From: wabbott@townshend.Corp.Megatest.COM (William Abbott)
Subject: Re: Cold Start
I was staying out of this dicussion since I've not jump-started
an FI bus, but the comment about jump starting burping raw gas into the
catalyst and that overheating and frying itself and everything close by
was too much. Prudent caution and post-moderen paranoia are two different
things.
0) Properly done, a jump start- taking electrical power from
another vehicle or a heavy-duty charger, is NOT ANY DIFFERNT from staring
your car normally. You turn the key, the regular starting stuff happen.
Its possible a *PUSH* start of a computerized FI car could blow
some raw fuel through the engine, but not much, and not for long, and
in any event, the catalyst has to warm up to work. Small amounts of
excess fuel are going to evaporate.
Catalysts DO melt down from excess fuel, but this is not small
amounts- when the O2 sensor on the exhaust pipe fails and the car runs
full-rich for significant distances, then you get catalyst damage. Not
on a whif of raw gas during starting.
1) If you have a similar vehicle, you can obviously jump-start,
since the electrical systems are the same. Whatever a 52-94 Bus needs
and emits are clearly not going to damage another bus of similar vintage.
2) I HAVE jump started my 914, which is a D-JET electronic Fuel
Injection. I HAVE jump started my late wife's 85 Golf, with K-JET and
a digital idle stabalizer. Both of these had some "computer" boxes, as
opposed to my 77 Rabbit or 69 Bus. I'd happily accept or give a jump
from any VW product to any other. Old American or Japanese junkers might
give me pause, but provided both cars are in otherwise reasonable condition,
a properly done jump is very unlikely to hurt anything.
3) A proper jump means several things, done correctly:
3.1) The recipiant battery needs to have correct electrolyte level,
be clean, well connected, etc.
3.2) Connect negative to negative first, at the battery terminals.
3.3) Start the donor car, if it is not already running and
get it idling.
3.4) Connect the postive termnials, battery to battery,
3.5) WAIT. Let the donor charge-up the recipiant's battery for a while.
3.6) After five minutes or so, try starting the recipiant.
3.7) Recipiant won't crank? WAIT another 5 minutes.
3.8) If the recipiant still won't crank, try running the donor up
to 2500 or 3000 rpm for a minute, and try again.
3.9) If this doens't do it, you need more than a jump start.
OF COURSE, your milage may vary. I know that ham radios over 10
Watts will kill late-model Toyota engine computers. But your FI bus has
nothing to fear from the AAA tow truck or other jump start source.
Shiny side up, rubber side down!
Cheers!
Bill
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