Oil flow problem on initial prime

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maw

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Hello folks,

Prior to firing our fresh 360 build we brought up oil pressure using a drill motor and hex shaft (intermediate shaft was pulled). Using a SW mechanical gauge we instantly had 80PSI. After a few second we expected to see oil beginning to flow in the rocker shafts but it never appeared.

We uncrewed the gauge and checked flow through the meter hose, we get a good solid stream. Meter put back in place.

With a flashlight we could see plenty of oil puddling up in the lifter valley. We pulled the rocker shafts and tried again, no oil coming up the transfer ports in the head. We've now pulled the heads and no oil coming through the oil passage in the block deck.

What's happened to oil flow to the top end, both sides are experiencing the same problem BTW? It looks like the lifters are fed from passages that supply the #2 and #4 cam bearings as well as the top ends. Or do I have a misguided understanding of the oil routing.

Thanks for any and all help.

Cheers, Mark
 
while one of you uses the drill to prime, the other should slooooowly turn the crank with a break over bar and 1.25" socket and you will soon find you have oil at the top end. :headbang:

sb
 
Your correct in your understanding of the oil flow path except you missed the part where the oil feed holes in the cam have to be lined up to the holes in the bearings that go up to the head (unless your cam has a groove in it for full time oiling and most cams don't have this groove). Their only lined up every 120 cam degrees IIRC so the oiling to the rockers only happens momentarily, not full time. So when your turning it over with the bar you'll eventually get to the point where their lined up and oil will flow.
 
You can take the cam out and have a shop put a small groove on both cam journals that have the through holes. Then you will have oil to the rockers full time. With 80 psi it sounds like you could stand to loose some pressure anyway.
 
Thanks guys, we're putting it back together again now. Should have posed the question before ripping the top end off.

Cheers, Mark
 
Maw, when you get it back together, turn the crank a couple of degrees at a time untill you vaerify oil to the rockers on one bank, mark the crank with a hash mark to idenify that position and continue turning crank untill you get oil to rockers on other bank,..again mark the crank position. In the future it will be as easily done as to line up the marks and verify oil pressure to both banks rockers. Terry.
 
If you have a drilled cam it is not recommended that you put grooves in the journals. You can either have a solid cam core and use grooves or a cam with oil holes and no grooves. Cam manufacturers say it weakens the cam to do both.


Chuck
 
I couldn't get oil pressure on my 440 many years back. Turns out I forgot to put a plug in the front of the block under the timing chain cover.
I guess thats why you should check pressure before you start up.
Rod
 
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