Good oil pressure but no oil in heads

Status
Not open for further replies.

fly_25

Greasemonkey
Oct 20, 2020
136
67
28
So I bought a used V6 for a project and finally finished with the installation, primed the oil with the starter and got good oil pressure on the gauge about 2/3 to max, when I start the car I see no oil flowing through the heads and the valve train looks pretty dry. Even when I rev the engine a little there seems to be no oil to the heads. Oil pressure is still good at idle. Could the oil passages be clogged?
 

fly_25

Greasemonkey
Oct 20, 2020
136
67
28
Here's a picture of inside the valve cover, looks a little dry to me and it doesn't change with the engine running
PXL_20220717_222956325.jpg
 

Tony1968

Royal Smart Person
Supporting Member
Jul 1, 2018
2,313
5,099
113
NW Indiana
At minimum I'd pull a valve cover then loosen a rocker to get a look through a push rod. Looks like a lot of caked up nastiness in there
 
  • Like
Reactions: 1 users

fly_25

Greasemonkey
Oct 20, 2020
136
67
28
Good idea, I'll try that tomorrow morning and see if I can clean the pushrods
 

ELCAM

Royal Smart Person
Jun 19, 2021
1,114
1,247
113
You need to pull the valve cover and see if there is oil at the first rockers. The oil flows through a passage into the head at the first pedestal for the rocker shaft and then the oil flows through the rocker shaft to the rockers.

Something could be plugged or misaligned or assembled incorrectly blocking the oil flow. Some rocker shaft engines can be assembled with the shafts upside down blocking the oil flow.

th-1162638090.jpg
 
  • Winner
Reactions: 1 user

fly_25

Greasemonkey
Oct 20, 2020
136
67
28
Is this true for the V6 or all sbc engines? I thought the oil flows up through the pushrods. Sorry I don't know too much about engines!
 

ELCAM

Royal Smart Person
Jun 19, 2021
1,114
1,247
113
Buick engines have rocker shafts. Chevys are a different design.

Edited to add:

Look at your picture you can see the rocker shaft. All the baked on grunge suggests to me that the oil was changed very infrequently. Later in its life someone likely used diesel fuel, ATF or some mystery stuff in a can to clean it up.
Since you also posted a pic of the bypass valve being damaged (https://gbodyforum.com/threads/what-is-this-and-is-it-still-functional.84832/#post-897073) they ran it till so much crap accumulated in the oil filter it bypassed the oil filter and pumped all the garbage into the oil system.
 
Last edited:
  • Like
  • Winner
Reactions: 1 users

fly_25

Greasemonkey
Oct 20, 2020
136
67
28
That makes sense, I hope the engine is okay then. I don't see how the oil can pass through the rocker shaft, am I missing something here?
PXL_20220720_153812331.jpg
 
Status
Not open for further replies.

GBodyForum is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to amazon.com. Amazon, the Amazon logo, AmazonSupply, and the AmazonSupply logo are trademarks of Amazon.com, Inc. or its affiliates.

Please support GBodyForum Sponsors

Classic Truck Consoles Dixie Restoration Depot UMI Performance

Contact [email protected] for info on becoming a sponsor