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Bruce in Bangkok Bruce in Bangkok is offline
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First recorded activity by BoatBanter: Jul 2007
Posts: 81
Default Low Oil Pressure at Idle, Volvo AD31B in the Tropics

On Thu, 25 Oct 2007 12:04:53 GMT, Brian Whatcott
wrote:

On Thu, 25 Oct 2007 11:05:13 +0100, "Alec"
wrote:

...
Try a heavier grade of oil, not one of the modern wide range synthetic or
semi synthetics multigrades.


Alec


I'm not arguing with this general advice. But the sentence I
quoted shows a mindset that may not tie to reality.

A synthetic almost as thin as water when cold, can STILL be thicker
than a thick mineral oil when really hot. Its viscosity vs
temperature slope is that much flatter. That's why they are rated
multi-grade. The synthetic doesn't burn off and has better high
pressure film strength.

Brian W



One thing to try before anything else is pull the oil cooler and see
whether it is stopped up. If you have ever broken a water pump
impeller the bits are still probably in the inlet of the oil cooler.

I nearly went crazy trying to solve a similar problem after a fellow
ran aground on a mud bank. Finally discovered the heat exchanger tubes
full of mud after someone told me the boat had been aground and I
noticed there was no inlet strainer.


Bruce-in-Bangkok
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