[Roadsters] Low Oil Pressure

[dave]

Bill, I think there is a plug with a tiny restriction that goes behind the
timing chain tensioner. I know there was one on the H20 I tore down.  If
that was left out, might explain the pressure loss and lack of flow to the
top.  You need to remove the tensioner to check for it, but easier than
pulling the engine.  
There may be other plugs like it somewhere else too, but I remember that
one.
Hope it's something simple like that.

Dave Brisco

-----Original Message-----
From: Bill Cole [mailto:datrock at centurytel.net] 
Sent: Sunday, May 31, 2009 1:50 PM
To: datsun-roadsters at autox.team.net
Subject: [Roadsters] Low Oil Pressure

Hi every body, I have a 3 main R-16 that has very low oil pressure. 
Maximum pressure is in the mid 30's. The engine was recently assembled 
and it came in pieces so I have no idea if it had pressure issues before 
it was torn down for the rebuild. Until recently I just assumed the 
gauge was off, then I hooked up a mechanical one and it read lower than 
I would have liked to have seen. I started out with 30wt and now have 
20-50 in it.
       The engine has less than 1000 miles since the rebuild, last week 
I rechecked the rods bearings, front and middle mains from under the car 
with plasticgage and they showed .0015-.002 range. I changed oil pump 
from another 3 main parts engine, I even honed the backing plate to get 
better tolerance and to take away what little wear marks it had on it. I 
tested the pumps and the one that is now in the car pumped better than 
the one I removed. I changed the rocker assembly in case it was causing 
the problem. All that and it still has low pressure on the original and 
on a mechanical gauge too, 10lbs under 2000 RPM and over 2000 RPM. it 
goes up into the 30's. So today I removed the coil wire, spark plugs, 
and the rocker arm assembly and turned the engine over with the starter, 
it went very fast to where I expected oil to surface from the galley 
going up threw the head to lube the rockers, nothing appeared, are my 
expectations wrong, I would have expected oil to flow.
    I'm leaning toward pulling the engine and rechecking everything 
inside. More than likely will also re-bearing it. Any suggestions would 
be appreciated, or if you had similar issues with a rebuild I would like 
to find out what the problem was, it may help me keep the original 
engine in the car. Thanks... Bill