View single post by Greg Fletcher
 Posted: 03-24-2010 09:48 pm
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Greg Fletcher



Joined: 03-11-2005
Location: Lake Nacimiento, California USA
Posts: 430
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 I'd only use a traditional 20w50 oil in this engine, but I doubt that is the nature of your problem. I would also avoid running the engine with no oil pressure as that can result in catastrophic failure in a short time. Oil pressure should build up in a few seconds, 1-2 minutes indicates significant issues.

On the 907, very poor oil pressure can be caused by wear on the main bearings, oil pump problems or even contamination in the oil pump relief valve in the oil pump housing as well as a broken or blocked oil pressure tube, so you'll have a number of things to investigate.

The oil pump is a fairly simple arrangement. The inner and outer rotor are what create the pumping action. These run a tight clearance and significant mileage will make them sloppy, but not normally anything close to what you are describing. It's usually worth investigating the oil relief valve spring. I'd remove it, clean everything well and reinstall with a good quality moly lube.