The 'little blue thing' is probably a radio interference suppressor, for the
purposes of testing at least it can be disconnected. Do you have 12v on the
white when measured against the pump body i.e. is the ground OK? Are you
sure that second wire isn't the ground and you are seeing the effects of a
high-resistance fault? I have an electronic pump which has 12v and ground
wires going into it vis spades poking theough the end cap, which is clear;y
marked '+' and '-'. I would expect any electronic pump, and even one with a
diode, to be marked with the polarity. Internally my pump has a fixed
Hall-effect transistor and a reciprocating magnet, both relatively clearly
visible when the cover is off. The points pumps I have seen have the points
clearly visible. I don't trust electronic pumps, mine has played up a
little, and when one of those starts playing up there is nothing you can do
about it except swap it out, a lot more difficult that givimg the points a
tickle or the pump body a clout.
PaulH.
----- Original Message -----
From: Ken Waringa <kwaringa@dynsys.com>
To: MG <mgs@autox.team.net>
Sent: Monday, December 11, 2000 1:56 PM
Subject: Fuel Pump Questions
> Yesterday I was going to move my son's 79 B outside to start wet sanding
it
> in preparation for painting. Started up, ran for a few seconds and died.
> Turns out the fuel pump isn't pumping. I have 12 volts on a white wire to
> the pump. Just before the pump the wire splits into 2 legs, one goes to
the
> pump, the other to a little blue thing bolted to the body by the same bolt
> that holds the pump cover.
>
> First questions, what's the blue thing?
>
> Now to the pump. The wire goes into the rear of the pump. When the cover
> is removed I see the wire goes into the pump, then comes back out and goes
> to a white wire that goes back into the pump, about 1 inch forward on the
> left side. I have 12 volts going into the rear of the pump, but only
about
> 3-4 volts coming back out. The rear of the pump appears to be filled with
> potting compound of some kind, no points visible. Would this be an
> electronic SU pump on a 79 B? I looked at the catalogs and they list the
> points type and the electronic for the car. I guess that means both can
be
> used, but which came original?
>
> I have an older SU pump that I'm going to install tonight so I can move
the
> car around while I continue to get it ready for painting. I'm not sure of
> the age, history of my replacement pump so I'm weary of leaving it in. My
> son is going to have the car at college, so I need it to be fairly
reliable,
> but I'm also about broke getting it ready for him. Any recommendations on
> which way to proceed would be appreciated.
>
> And for the last question, can anyone tell me where the inertia switch is
> located? I see it on the schematic, but can't find it.
>
> Thanks,
>
> Ken Waringa
|