Still working on a 22re that I have rebuilt from top to bottom. After initial start, oil pressure light blinks on and off. Manual pressure guage reads 25 psi and then quickly drops to 10 psi or so. We checked oil pump and galley plugs. All seem fine so we pulled a main bearing and a rod bearing. The bearings have scrapes and look like debris in the passages have passed through. No significant damage. I also found a small turning in the bottom of the pan which could only have come from the crankshaft being gound or the mains being turned. Certainly don't want to pull the engine and pull it back down, but want to find a solution. We cleaned the block and crank before assembly, but suspect the oil passages might have been overlooked. Can any make suggestions on how to clean the oil passages without ripping the engine out? Any able to describe the complete path oil takes after being sucked up by the pickup tube?

 

The oil is taken up into the block and delivered through the block's main saddles, in through the top bearings and crank journals where it then also reaches to the rod bearings and their saddles. All the while it's also being pump through the front end of the block, into the timing assembly and on up to the top end through the cam, bearings, and bathing the valve train assembly. All of this is by means of the little holes/ports you'll find machined into the moving parts. It makes more sense if you were to actually see it all.

Anyway, a block in the oil galleries would increase oil pressure....not lower it. And, it's not the pump that creates the pressure, it's the resistance to flow within the motor. There's the relief valve on the oil pump that's designed to open in the case of excessive pressure. If it sticks open, the motor will have trouble building pressure.

There are a number of reasons you could be experiencing low pressure....the relief valve only being one. First, verify the sending is working properly and has good connections. Also, read this link here:
http://www.aa1car.com/library/2005/us020516.htm
It will explain more than I can (rather, want to....) in this post. Me fingers are lazy today. Stho stharry!

 

x2 on what he said me i just drove from bear creek WI to san deigo CA and when i left she only had about 4k on the clock and half way here oil presure was only just below the lowest mark not the bottom one but the next one all the way here i know i have flow i opened the oil cap when it was running looks cool but man is a mess to clean up anyways its not the presure you need its the flow here is an ex ....

get a glass of water and two straws one big one and one big one with you pinching it now take the big one and drink see no presure to get it up and all the flow in the world right now pinch it see lots of presure to get it up and not alot of water your motor is the same here less pressure means more flow most of the time so just check if theres any oil flow start it and open the oil cap see if it sprays out and all over the place hope it helps man im out

 

Thanks guys! I am pulling the pump and the bearings, replacing both.