Re: The Buzzing Bees

[Aleksander Mierzwa <alex@matrix.pl>]

At 13:05 99-04-14 -0400, Douglas Quebbeman wrote:

>I've meant to ask about this sooner, but I've been listening to the buzzing
>bee in the back
>of my 86 5ktq for about a year now. I figure that probably puts me in
>double-overtime w/r/t
>the likelyhood of fuel pump failure, but I want to be sure...

If the noise is steady and not very loud, it doesn't necessarily say that
the pump is about to fail. Most replacement Bosch pumps start to produce
similar noise several weeks after being installed - BTDT on my car, and
several other listers who recently installed Bosch pumps it their cars
reported the same. You should start to worry if the pump suddenly gets much
louder during driving. This rapid change in sound is usually accompanied
with driveability problems, at least these were the symptoms on my car.

>Are there two different pumps, one noisier than the other? Seems like I
>remember something
>like that, a Pierburg vs. Bosch comparison. 

AFAIK the Pierburg pump is not a direct replacement and requires purchasing
several other components (pump holder, fuel line), which are not cheap.
This pump is supposed to be very quiet, though. Replacement Bosch pumps are
currently being produced in Czech Republic and it seems that their quality
isn't very good - they become noisy couple of weeks after being installed.
I got quite frustrated when my new pump started to buzz, but then I learned
they all do that and given the driveability problems went away, I learned
to live with that. BTW, the screen on my old fuel pump was absolutely free
from any debris. The pump is also louder as the temperature drops.

>Lastly, should I try to have a nearly empty tank when I undertake the
>replacement? And
>are there any gotchas or BTDTs that aren't covered by Bentley?

Yes, you should definitely wait until the fuel gauge needle is at red area.
Other than that, I found the job to be pretty easy. It helps to have a
fluorescent inspection lamp (NEVER use a lamp with filament bulb for this
job) to see inside the tank.

Aleksander Mierzwa
Warsaw, Poland
mailto:alex@matrix.pl
87 Audi 5000CS turbo (mine)
88 Renault Medallion wagon (mom's)
91 mountain bike (just in case both cars break at the same time :-)