Now that the Jaguar name calling hoo hah has died done lets get down
to some dirty technical stuff.
The recent posting about oil pressure in an MGB has got me to
thinking about my Series I E-Type with a 4.2 l engine. When the engine
is cold the oil pressure comes up to around 50psi at 2000 rpm. After
an extended cruise down the highway when everything is really hot then
the gauge reads very low and at low revs doesn't register anything.
Now the gauge is a complicated electromechanical affair with a sender
consisting of heating elements and bimetallic strips and similarly for
the gauge. Overly complicated but it does avoid spraying oil in the
cockpit like in some LBCs. So I always assumed this behaviour
was just temperature effects in the gauge itself.
But now I am worried that as the engine warms up it is the slop on the
bearings increasing. I had never thought about it before that oil pressure
is an indicator of bearing wear. Sounds reasonable though. But what is
important for efficient lubrication: oil pressure or is it the flow rate
of oil through the bearing? I have had this same argument with my self
when deciding which oil viscosity grade to put in.
Maybe I can start an argument about multi grade vs high viscosity vs
these new synthetic oils!
As I was driving home the other night in my mechanically sound but
as yet unpainted E (Re: Looking for an SF area paint job) I was shamed
at the traffic light as a glorious black laquered E of identical model
and year pulled alongside. We wound down our respective windows so
that I could hear his derisive laughter more clearly. He said he was
admiring my oil leak which I considered to be a very droll in joke
about Jaguars since in fact the underside of my E is untypically clean
and dry. But when I reached home a mile later I was horrified to see a
trail of oil leading up the driveway. Thats what happens when you have
an oil gauge you don't bother consulting anymore.
Well the leak was a loose drain plug on the filter.
This turned out to be a stripped thread on the alloy casting that is
between the block and the filter. A reminder never to let garage
mechanics even change the oil on a Jaguar. On my previous E a similar
thing had happened when a mechanic cross threaded the drain plug in
the sump pan. So the filter plug I had to replace with an oversized
one after drilling and tapping the alloy housing.
Patrick Krecik - expatriat Aussie bastard cruisin in California.