Re: oil pressure 75 TwinSpark?

[Jonathan Coates <cdico.demon.co.uk@xxxxxxxxxxxxxxxxx>]

In message , Lars Arvidsson <arvid@domain.elided> writes
>Hello friends out there!
>I'm a little worried over the oil pressure readings in my 75 twinspark
>'90, 160000 km
>When the engine is cool, I get abt. 3.5 bar (51 psi) at 2000 rpms.
>As the engine heats up, the oil pressure decreases, of course, and gets
>more
>direct associated to the rev. But, a few minutes after 80 deg C is
>reached, the pressure suddenly drops
>to abt 1 bar (14.5 psi) at even as high rpms as 3000. At idle the needle
>doesn't even get of it's rest...
>The oil I use is Castrol RS 10W-60.  What I find unusual is the sudden
>drop of pressure.
>I guess there are some pressure regulation stuff inside the oil pump
>(springs and balls?)
>Can they cause this behavior? Or can a oil pressure sensor be this
>tricky?
>Or a worn-out oil pump...
>All suggestions are welcome.
Mine has this same oil pressure behaviour which I think could be related
to the lack of performance. I don't know how much oil pressure is needed
to work the VIVT unit, but if mine hasn't got enough then that's why the
performance is down.
Can anybody tell us if the 2 litre twinspark engine has the notorious
crankshaft plugs, and if so can I get some more and beat them in with
the engine in the car, by taking the sump off? I want to do this without
damaging the engine of course! I believe that the plugs are aluminium,
does anybody know if Al gets brittle if overcooled? How cold is cold
enough, I understand that Mr Di Matteo recommends chilling the plugs
prior to fitting, like -18C, -200C ?
While I'm in there is it worth changing the big end shells? I only ever
did this once on a Morris 1000, tip of the day is empty the sump before
you pour it all down yourself.
Little aside Re Morris 1000, I wound it up the ramps on the starting
handle (see film Ice Cold in Alex) and completed the whole job in under
two hours.
- -- 
Jonathan Coates
33 wagon daily driver
164LV6 in bits
752.0TS T car
Alfetta 2.0 GTV

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