need help with low oil pressure problem

[70 RAG TOP]

 I am also concerned about the oil pressure on my freshly rebuilt eng.(383)
I finally got it running and did the break in on the cam .  Im worried because my mechanical gauge(after market) is only showing 22psi at 1000rpm(which seems a little fast for an idle) .  The manual states it should be  20psi@500rpm, but at that rpm, my gauge is only showing around 8psiand my "dummy"light is flickering.  I also took the line off of my gauge and allowed some oil to flow out, because it had some air bubbles in it.  ( A mopar friend suggested that I could have an issue with my oil pick-up possibly being too close to the bottom of the pan.  The funny thing is, is there are ticking noises or any other noises that would go along with low oil pressure.

WHAT I HAVE:
Stock rebuild, new hi po oil pump, new oil pan(from 440 source ,not an exact match to my old 402 pan. it did not have the same slope on the shallow end of the pan, which also caused a clearance problem with the steering control arm), oil pump pick up(440 source which I had to alter (shortened the length by cutting off a little of the threaded end) because pick up was hitting on bottom of pan and keeping the pan from seating on the block) , windage tray with 2 gaskets, Comp Cams break-in oil.   For my oil pressure guage and dummy light, I have a"T"  fitting coming off of one of the oil ports on the rear of the engine.


Could the gauge be bad?
Could the "T" fitting cause a problem?
Could the port be clogged (should I try the other port)?
What should the correct distance be between the pan and the bottom of the pick-up ?(if it is touching the bottom, could this be my problem)?

One other thing, the engine had the same problem(low oil pressure/dummy light flickering at idle)before I had it rebuilt.  I am wondering if maybe the guy who rebuilt it, hot tanked the engine but didn't run brushes through the oil gallies.  He hasn't had the courtesy to return my calls.

thanks
Mike

[Chryco Psycho]

good news is the pump is on the outside & easily swapped out so I would pick up a new Melling High Pressure not high volume pump & swap it, , I have seen other makes of pumps have problems , hopefully this will solve your issue  the other thing you can do is to shim up the pressure by installing a short 1/4 bolt into the spring

[brads70]

If your running as fram oil filter, swap it out for a WIX . Many times I've seen fram filters fail and cause low/no oil pressure.

[72cudamaan]

If your running as fram oil filter, swap it out for a WIX . Many times I've seen fram filters fail and cause low/no oil pressure.

Brad...I don't buy that. But I say that only because I don't understand it. I have heard this statement before but
I don't comprehend how a filter failing could lower your oil pressure. Can you explain it to me so I can learn from it?
                     
I will be the first to admit I don't know everything! 

[brads70]

Brad...I don't buy that. But I say that only because I don't understand it. I have heard this statement before but
I don't comprehend how a filter failing could lower your oil pressure. Can you explain it to me so I can learn from it?
                     
I will be the first to admit I don't know everything! 

I belive it has something to do with the by pass? not 100% sure? I have seen it happen a good dozen times at the stock car track I work at. Racecar comes off the track... long faces... I go over and ask whats wrong. "No oil pressure" First thing I do is look at the oil filter and if it's a fram I either tell them or if they don't believe me I go to the parts trailer and get them a WIX and say install it and start it up.
Many times ( but not always) that was the issue. I'm not entirely sure why.... but I look like a genius when it works out.  .... and trust me I'm not! Don't see many/any fram oil filters at the track unless they are newbies much anymore. Word gets around....

[72cudamaan]

Thanks for the reply Brad. Maybe someone else will chime in.  ?
Still not saying you are wrong or didn't see it. Just doesn't make any sense.
Even if the bypass failed and full bypass was in effect, you would just send
unfiltered oil through the oiling system. Secondly, Collapsed filter?    Then you would get major increased o.p because of the blockage.
Dunno, just interested in ideas on the subject. But I do agree, Wix is the best filter on the market today.
I believe years ago Hastings had the right idea. Unfortunately Consumer Reports didn't
think so and their write- up put Hastings out of business. 

[mopar12372]

(oil pump )bypass dosent necessarily mean you get full oil pressure it just means you some oilpressure.or what ever it allows.
when fram was made by allied signal i would say brad was wrong but hes right . the bypass in the oil filter  is made from cardboard and oil just flows every where , COULD cause an oil pressure issue . heres a great question with mopar oilfilters being sold at wallmart for 6.00 why not buy one of them or a fl1a fomoco?
it is very important for the engine builder to install the cam bearings and rocker shafts properly . IMOP i would get a known correct reading gauge test pressure and go from there . start simple with your corrections then move forward with what ever you come up with. t fitting unless its leaking or clogged doubt it. screen too high ok proper screen height is important  because if too high the pump could run dry at higher rpm too close to the pan could cause low to zero  psi. the book says how to measure clearance.   
the best of luck !!!

[72cudamaan]

How could  it cause low oil pressure. If the bypass fails, all it did is create
a secondary oil reservoir. If you eliminate the filter all together that would
be the same thing ,wouldn't it?

[72cudamaan]

Man I  wish the chatroom was working. Sure would make it easier
and more interesting. 

[jimynick]

Andy, you can't have oil pressure if you don't have the oil to pressurize. If the filter bunged the oil suction side, there would be no oil for the pump to pump. Capice? 

[70 RAG TOP]

FYI  I have a Napa gold(black) filter.  Isn't that actually a wix brand filter?   I appreciate your input, and I plan to start with the easy things to check and go up from there.
One more question: could the windage tray be slowing down the oil that is trying to get back to the bottom of the pan  enough to starve the pump of oil?

Thanks
Mike

[mopar12372]

thats why fram filters made of cardboard  are junk ..../....... once they get saturated with oil / gets hot it most of the time brakes loose and dosent do a damn thing but cause problems . most people dont notice because they dont use a oil pressure gauge and the factory idiot light comes on below 5psi wich is too late or they try a new filter the problem goes away .the gauges that come on some newer cars move but they are no better than a idiot light . they havent any #s just sweep back and fourth and most drivers dont pay attention anyway . look inside a fram filter /stp/ house filter paper trash not good  . mobil filters mopar filters fl1a fomoco wix baldwin napa gold (wix) = good . it doesnt happen often enough for anyone to really notice thats probably why you dont understand . if you would like i have a web site i can get ahold of for you to see with your own eyes. hope this helps

[mopar12372]

FYI  I have a Napa gold(black) filter.  Isn't that actually a wix brand filter?   I appreciate your input, and I plan to start with the easy things to check and go up from there.
One more question: could the windage tray be slowing down the oil that is trying to get back to the bottom of the pan  enough to starve the pump of oil?

Thanks
Mike

at high rpm yes  if you dont have the proper depth pan for every 1000 rpm you need 1qt
the pick up tube is below the tray under all that fresh oil i hope
 since you asked that question how many quarts of oil did you put in the pan? how many does it hold

[70 RAG TOP]

it is a stock pan, about 5-1/2 qts w/filter is what it calls for.  Would it hurt anything to overfill it a little(such as a 1/2 qt)?  I have heard that too much oil can cause stress on seals.  is that true/false?

[Strawdawg]

The main thing too much oil does is allow cavitation resulting from the crank journals/rod ends whipping thru the oil due to its higher level.  When this happens you are pumping air into the oil passages and this leads to a short life for the engine.