I'm behind in reading my British car mail, so forgive me if this subject
has already been put to rest. Scott Paisley asked last week about high
oil pressure on startup in his TR6.
Scott, I have an '83 Volkswagon GTI with identical symptoms. It has
about 130K miles on it, doesn't burn a drop of oil, and doesn't leak oil
anywhere. It's probably not appropriate to draw too many conclusions
about how your engine will perform based on how mine performs. However,
oil pressure shoots up above #130 when I start up cold, and then settles
down to normal (which is abundant, about like yours) once warm. This is
the original motor in its original configuration---never had anything
done to it.
I'll try to get around to checking the oil pressure relief valve on my
TR6 this weekend to see if it has the same detend you describe on yours,
preventing the spring from bottoming out in the assembly bolt. I'm in
the process of re-installing the motor after having it rebuilt, and I
want to get a few other things done before I pull that plug back out.
But I'll do it soon, while it's still relatively accessible.
In the end, though, I think your motor is fine. I don't have experience
with high-oil-pressure-related failure of seals, but I expect that the
failure would be sudden, at peak pressure, and not gradual, for instance
as the result of repeated high pressure. I think the greatest danger,
if there is any problem at all, would be degradation of the oil under
high pressure. I don't know the extreme pressure range under which
motor oil is designed to operate (Lee Daniels, is this related to your
field? Bill Sohl, you seem to have a head for details?), but I would
expect #100 to be well within it.
So, your oil pressure may be unnecessarily high---causing the oil to
deteriorate faster and the engine to run hotter, perhaps---in which case
you'd be right to fix it. But I wouldn't expect it to be a critical
problem. And, on the other hand, it's not improbable that everything is
operating normally. As I said, I'll try to get around to checking my
own TR6 ASAP.
Kevin Riggs
(205) 730-3074
work@riggs.b30.ingr.com
|