Paul,

What sort of oil are you using i.e. brand & grade. Your oil pressure
shouldn't drop much below 90% of relief spec which is just shy of 60 psi
(400 kpa). On the street L engines weren't designed to run synthetic oils
i.e. Mobile 1 etc. Most L engines in reasonable condition will use very
little GTX, Pennzoil or Penrite 10w50 between changes, a litre or so of GTX2
or Valvoline XLD or Helix etc is quite normal but generally no shear is
evident except in very high temperatures for prolonged use, and GTX3 and
similar oils in my humble opinion are mostly just a waste of time and money
unless you're racing - valve guide specs aren't close enough usually and
these oils just pour through the engine and out the exhaust especially in
the 2nd half of the change cycle.

Oil shear is explained on this link:
http://www.bobistheoilguy.com/oilshear.htm

regards
Terry

-----Original Message-----
From: [EMAIL PROTECTED]
[mailto:[EMAIL PROTECTED]]On Behalf Of Paul Stanley
Sent: Monday, 27 January 2003 8:52 PM
To: [EMAIL PROTECTED]
Subject: Re: engine confusion...


Sorry I dont know anything much about engines, but on slightly the same
subject, I noticed on a hot day with the AC on I can get my L20B to nearly
200 deg F and the oil pressure drops down at least a 3rd of what it would
run on an average 22 degree day.  Is that a sign of a worn oil pump or just
the oil losing viscosity?  Is oil too thin a bad thing?

From: Paul Stanley




----- Original Message -----
From: David Andrews <[EMAIL PROTECTED]>
To: <[EMAIL PROTECTED]>
Sent: Monday, January 27, 2003 11:54 AM
Subject: Re: engine confusion...


> Well first thing to do is to run it richer on a cold day and see if that
> helps. That'll tell you if the mixture has anything to do with the oil
> consumption.
>
> Second thing is to perhaps try a different weight oil as the heat will be
> lowering the oil viscosity. Try both heavier and lighter and see how that
> affects it.
>
> Regards,
>
> Dave
>
> >>>>>>>>>>>>>>>>>> Original Message <<<<<<<<<<<<<<<<<<
>
> On 1/27/03, 12:20:26 PM, "mark krawczuk" <[EMAIL PROTECTED]> wrote
> regarding Re: engine confusion...:
>
>
> > thats true,  the  compression rings seal the chamber, and the oil rings
> just
> > scrape away the excess oil from the  bores, and if these are worn will
> allow
> > to much oil  on the bores and get into the chamber.
>
> > mark k
> > ----- Original Message -----
> > From: "andrew smith" <[EMAIL PROTECTED]>
> > To: <[EMAIL PROTECTED]>
> > Sent: Monday, January 27, 2003 11:25 AM
> > Subject: Re: engine confusion...
>
>
> > > Unfortunatly compression testing doesnt allways give a true indication
of
> > oil
> > > consumption.Valve guides will just about allways give a puff of smoke
on
> > start
> > > up if they are worn.Sounds like it might have weak oil control
> rings.(just
> > a
> > > guess).Runing better in hot wheather sounds like it is lean on cold
> > days.It
> > > must be nearly at the surge stage on cold days for you to notice the
> > > difference.Not blowing smoke on hot days has me stumped.
> > > On my mates drag car we would get it setup right during qualafying(hot
> > > daytime) and then during eliminations(cold nights) it would run slower
> and
> > > would be knocked out in the first round.If you cant run within a
couple
> of
> > > hundreths of your dial in then you get knocked out.We are now getting
a
> > much
> > > better handle on the night time tune and let it run slower during
> > qualifying.
> > >
> > > "GREENBURY, Andrew Robert" wrote:
> > >
> > > > Hi everyone,
> > > >
> > > > The condition of my L18 has seemed to be getting worse and worse -
> > blowing
> > > > more and more clouds of smoke predominantly after a closed throttle
> > > > (taking off, after coasting down a hill etc). Its now doing it
> > > > consistently after every coastdown.
> > > >
> > > > However a compression test revealed a consistent 176 psi (at WOT
cold)
> > in
> > > > all cylinders, so I thought it might be the valve seals.
> > > >
> > > > Now the weird thing is in our hot Melbourne weather the car runs
much
> > much
> > > > better (runs smoother, more responsive, less harsh). And the really
> > weird
> > > > thing is in 40+deg weather Saturday, the engine didnt blow any smoke
at
> > > > all, even after coasting down big hills that usually have bellowing
> > clouds
> > > > pumping out.
> > > >
> > > > So the reasons for all this have got me stumped. Something I thought
may
> > > > be a factor was that the atmospheric changes (temp, pressure) has
the
> > > > engine sucking less air for the same amount of fuel ie running
richer in
> > > > the hot weather, therefore the engine was running lean before.
> > > >
> > > > I also thought maybe for some reason the engine is sucking blowby in
> > > > excessively, adversely affecting combustion performance, but how all
> > this
> > > > relates to better performance and very little smoke in hot weather
> > > > compared to normal has got me stumped...
> > > >
> > > > Any thoughts on this would be greatly appreciated,
> > > > Andrew
> > > >
> > >
> > >
>
>
>



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