Oil pressure quesiton...

Postby MLMFLCN » 05 Sep 2010 22:51

Had an oil pressure question. Under fairly hard acceleration, oil pressure goes up to about 80, then dips to about 40 and then back up to 80. Thought it was my electric gauge acting up, so I hooked up a mechanical, and the two followed the same pattern. Is this normal? I usually don't look down, but had a friend in the car with me today who noticed it. At idle and a hot engine, the pressure is always near 35 - 40 lbs.

Also, looks like since the rebuild, the engine has consumed about ½ a quart of oil. There are about 250 - 300 miles on the rebuild, is this still normal?

No white smoke or anything while running.

Thanks for any help...

- Rich
User avatar
MLMFLCN
Frequent Poster
 
Posts: 238
Joined: 10 Oct 2005 13:24
Location: Ohio

Postby dave-r » 06 Sep 2010 7:52

No it is not normal to use that much oil.

As for the pressure. It could be the oil pickup being uncovered during acceleration and sucking air.
You have a baffled sump and good windage tray or crank scraper I hope?
User avatar
dave-r
Grumpy Old Man
 
Posts: 9842
Joined: 12 Oct 2003 21:45
Location: North of the Tyne, England

Postby MLMFLCN » 06 Sep 2010 11:59

I do have a windage tray, but the pan is not baffled.

The pan and pickup were a MP combo kit. 5 QT capacity. Engine is nearly stock, so it seemed appropriate. Is the drop in pressure an issue? Seems at 40 lbs it wouldn't be.

I am doing an oil change from the break in oil, looking to use Brad Penn 10w-40 and a NAPA filter. Sound okay?

Thanks for the response.
User avatar
MLMFLCN
Frequent Poster
 
Posts: 238
Joined: 10 Oct 2005 13:24
Location: Ohio

Postby dave-r » 06 Sep 2010 12:19

I would use a real Wix filter even though the NAPA ones are supposed to be the same. One of the guys in my club had a NAPA filter balloon for no reason.
User avatar
dave-r
Grumpy Old Man
 
Posts: 9842
Joined: 12 Oct 2003 21:45
Location: North of the Tyne, England

Postby dave-r » 06 Sep 2010 12:21

Another thought. The MP widage tray does not have enough drain back holes and the existing slots are a bit too narrow. I always pry open the MP drain slots so the oil can return to the sump better.

If the pick-up is sucking air right when you need it I would worry about damaging the main bearings. Sump baffles are a very good idea.
User avatar
dave-r
Grumpy Old Man
 
Posts: 9842
Joined: 12 Oct 2003 21:45
Location: North of the Tyne, England