Engine Clatter & other questions

[LDMartin]

> Oil Weight: 5w30 as per Nissan recomm's

Good. Changing down to 5W-30 all but eliminated my cold clatter so I would
have recommended that. One of the new 0W-30 weights might be given a go to
see if it would get things flowing sooner.  I'm in the process of changing
to an ester based oil (Motul), the increased *clinginess* of which will
hopefully keep the top lubricated between runs.

> Mileage is 220k (sound appeared approx 2weeks ago - car used once a week
> since oct last year)

Is that miles or kilometers?  I notice your address is in Oz.  An SR20
should not wear out in 170K miles but the old girl is getting on a bit.
Might be time to have a pro look into it.

> Noise hasn't/Doesn't change. It disappears with slight revving, comes back
> after engine has settled
> into idle again.

Sure does sound like low oil pressure when you describe it that way.  Does
it idle at the normal 800-850?

> Loud enough to worry about

Best have someone take a look.  Before going though I would try a flush,
change the oil and filter again, replace the tensioner if it's never been
done (quite inexpensive and easy) and get her in to a trusted mechanic if
that doesn't help.  A stretched chain is always a possibility but yours has
not been run hard and is not a likely candidate in my opinion.

Never revving the engine over 5K is not a bad thing but I wonder if a
general conservative style is perhaps not allowing top side oiling to be
efficiently accomplished.  Every six months on the oil change doesn't say
how many miles.  Is it a lot of miles between changes?  Ordinarily that
should not be a great problem either but I remain concerned about sludge
buildup blocking some oil passages if that mileage is being gained in stop
and go or short trips.

Larry