Simon
I don't think that this statement about throw over is at all
meaningless. The reliable action of a pump depends entirely on the throw
over being correctly set. The diaphragm has to be rotated until whilst
pressing the centre the throw over fails. It then has to be turned back
to allow for slack, wear, diaphragm stretch and expansion etc.
Early instructions I believe said 4 holes but this has now been
increased in recent literature to 5 or 6. I know to my cost that the
early procedure gave problems. I had a pump that worked fine on the
bench but it would let me down when it got hot. I stripped it down three
or four times to try and find what was wrong. I then built a test rig
and pumped paraffin through at full flow rate for a long period. It took
over an hour before it failed and then I could see that there was no
throw over slack left. Then a colleague told me about the later
information. I just set the pump up accordingly and it has never failed
again after many hour of soak testing on the rig and road running over
the last four years or so.
Regards
>My thanks for the responses.
>
>My points are in, per the book, and seem to be working fine. The term, from
>the manual," throw-over" is fairly meaningless is it not? I interpreted that
>by touch and guesswork.
>
>My pump seemed to be a (typical) mixture. Condenser which leads me towards a
>later (BJish) original and single contact points which takes me backwards.
>(New ones are twin contacts).
>
>The points were worn down to nothing, just a sliver. Surprised that they
>weren't playing up.
>
>Diode is in and seems to work. I ran pump on the bench and it ran well (as
>well it might with nothing to pump). That is to say there were no sparks at
>contacts, so have fingers crossed for a happy ending.
>
>If all goes well, that is the car switched from pos to neg earth.
>
>
>
>Simon
--
John Harper
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