Re: Oil Surge

[Ian Soady <ian@domain.elided>]

In message , ggrunwald@domain.elided writes
>Here's a new topic for discussion which I can not remember seeing before.
>
>As I have mentioned on the list before I have fitted a small buzzer across
>my oil pressure light.  I did this as I felt it unlikely I would notice the
>light until it was too late, Particularly with the sun shinning on the
>dash.
>
>The other day I was descending a fairly steep hill and at the same time
>braking and turning right into a side street.  Lo and behold I heard my
>buzzer go off and a quick glance at my oil pressure gauge showed it
>plummeting to zero (see Mike they do have a use).  This all lasted about
>0.5 second and then recovered.  I diagnose it was oil surge.  This is
>particularly likely as the manoeuvre at the time would have most of the
>sump oil in the front left hand corner of the sump.  I checked my oil level
>when I got home and it was full to the top mark on the dipstick.  As a
>matter of interest I do have a oil tube on the block.
>
>I believe that I would never have noticed the above events without the
>buzzer as the pressure dip was for a very short time and I was too busy
>braking and cornering at that moment to be looking at dash lights.  I have
>been able to repeat the experience by using the same hill and corner and by
>very heavy braking.  Has anyone else experienced this?  Does the Stag sump
>have baffles?  In any case I would be interested in any comment.  I do not
>imagine a short and very infrequent dip in pressure will do significant
>harm, although other opinions are welcome.  In any case I do not know if
>there is anything I can do about it.
>
>If list members wish to test this on their cars they do so at their own
>risk.  Slamming on the brakes, throwing the car sideways to the right or
>any combination of these can lead to accidents or conflict with local
>constabulary.  If, in-spite of these words of caution, someone does try one
>of these manoeuvres I would be interested in knowing the outcome.
>
>Guy Grunwald
>77 Stag
>
I've also noticed this when testing the brakes prior to the UK MoT
roadworthiness test. It's quite frightening - although my pressure seems
to stay down for about 3 or 4 seconds on the gauge then slowly comes
back up. I don't know whether I should stop the engine under those
circumstances (although if I've just done a stop violent enough to cause
it under normal driving I expect I'd have other things to worry about!).
It seems that some kind of baffling in the sump might be a good idea???
Or would this reduce flow to the pump pickup?

To change the subject, there have been a few replies to my query earlier
this year re using unleaded. So far, no actual problems notified. I have
also asked the same question in the SOC magazine. Three (count them!)
replies - again all having used unleaded for various periods: no
evidence of problems. It's an awfully small response from such a large
population. 
-- 
Ian Soady