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Low oil pressure

The one

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I have a vp ss 5 litre it has 0 psi oil pressure at idle when hot I used a thicker oil than usual it raised oil pressure to 10 psi at idle and 60 psi at acceleration does that mean that clearances are out not the pick up is blocked that's why it raised it
 

MikeC

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I'd have a look at the oil pump relief valve before I started checking the bearings.
 

someguy360

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It won't be bearings if your getting that much pressure under acceleration.

You should be running at least a 20w50 in a stock 304 so if you've been running thinner than that it could explain your low pressure at idle. It's completely normal for a 304 with some k's to have as low as 4-5 psi at hot idle. General rule of thumb is as long as pressure goes up with revs which yours appears to be then you are ok.

Mine averages about 10psi on hot idle and 60psi at 4000RPM which is completely acceptable for these engines.

Even most workshop manuals say 4-5psi at idle is normal.

As said above, it's worth double checking the relief valve just to be sure.
 

immortality

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The trick with 304/308 engines is to NOT monitor oil pressure...
 

The one

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Yeah I was using valvoline 20w50 I changed to penrite hpr30 and oil pressure picked up i didnt know oil pressure can be that low I thought 20 psi at idle was the norm and right about monitoring oil pressure the more you look more things go wrong
 

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I thought 20 psi at idle was the norm
For a V6 yes, but the Holden V8 had a notoriously terrible oiling system, they'll last for 400,000km with next to no idle oil pressure. When you need to worry about oil pressure is when you aren't getting any with revs.
 

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I've never checked the oil pressure but Gregory's say you should have 48kPa minimum @500 rpm and 275-414 kPa @2000rpm- hot .
I use HPR 30 - the high zinc content means it's kind to any sliding surfaces in old engines- like cam faces.
 

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I use hpr15 and have better pressure than that. Although my bottom end is relatively low Km's.
 
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