Guest Posted June 28, 2001 Share Posted June 28, 2001 I have a 396 bored to 409. It is completely blueprinted, including the hi-volume oil pump. At 2,000 RPM it is reading 10 lbs pressure with warm oil. It has been explained that it has lots of volume but no pressure. Obvious! It has not blown up at 20,000 mi. I'm still not comfortable with this low pressure reading. I want to drop the pan and shim the oil pump spring. Can anyone tell me how much shim to use for how much pressure. This is a lot of work and I only want to do it once. Link to comment Share on other sites More sharing options...
chuckash Posted July 1, 2001 Share Posted July 1, 2001 I've been told somewhere that you need 10 psi oil pressure for every 1000 rpm's. 10 psi at 2000 doesn't seem healthy at all. I know this sounds simple, but check the gauge first if you didn't already. If you only have 10 psi at 2000, then at idle you wouldn't have hardly any, and I would have expected some damage by now. Just my opinion, but I wouldn't run the motor too much until this problem was resolved. Link to comment Share on other sites More sharing options...
Guest Posted July 1, 2001 Share Posted July 1, 2001 A new guage did give a better reading. This car is now shut down untill I resolve this issue. A call to JEG'S came up with a pump that will suck a stock pan dry. I have a home built 7 qt. pan on it. I will also check/replace the bearings. I will just about have to remove the engine to do this. I hope to also get this car painted before it see's the streets again. ------------------ George Lines Link to comment Share on other sites More sharing options...
superstk Posted July 2, 2001 Share Posted July 2, 2001 Check your oil pickup tube and screen. Screen canbe clogged or your pickup tube may be sucking air at the oil pump connection . Good idea is to weld the pickup tube to the oilpump. Also your pickup screen should be 1/8 of an inch from bottom of pan. If you plan on purchasing a new oil pump go with the Mellings M77-HV pump(I think thats the # for a BB) LOL. Hope this helps. Link to comment Share on other sites More sharing options...
Guest Posted July 11, 2001 Share Posted July 11, 2001 I received the new oil pump yesterday. It is a Moroso blueprinted, adjustable. JEG'S price is $107.99. Now I'm looking at a major project just to install it. I'll also change out the bearings whether they need it or not. I have to go now because I hear my Monte calling. The car has been very lonely without me. ------------------ George Lines Link to comment Share on other sites More sharing options...
Guest Posted April 29, 2002 Share Posted April 29, 2002 I finally got to the fix on this problem. Instead of removing the trans so the BB could be raised high enough for pan removal, I jacked the body up since the front end was off anyway. I hate removing transmissions. Anyway, I found the oil pump loose, hanging down about 1/16". Did I ever tighten it in the first place? I changed out all the bearings which were in suprisingly good shape. Only minor skuffing. How were they getting any oil at all? When I saw that loose oil pump, I figured that it would be engine removal time for a new crank. Oil pan is back on and ready to be fired again soon. I will take care of some other minor problems while the engine is hanging there including a complete engine/frame wash job before I get back to paint prep. Getting close to final paint color. ------------------ George Lines Link to comment Share on other sites More sharing options...
Guest Posted April 29, 2002 Share Posted April 29, 2002 So the oil pump was loose that cant be good!!! I do wonder how it was geting any presure at all.... or why it did not fall off.... ------------------ http://home.earthlink.net/~fadams6969/index.html Link to comment Share on other sites More sharing options...
Guest Posted April 29, 2002 Share Posted April 29, 2002 Yes, it was registering 20lbs when cold. The only thing keeping it from falling off was the windage screen. ------------------ George Lines Link to comment Share on other sites More sharing options...
Guest Posted April 30, 2002 Share Posted April 30, 2002 George, you may need to check your harmonic balancer, it may be bad! About the only things that will cause a oil pump to come loose or break are either the rotating assembly wasn't balanced or the dampner is bad causeing harmonic vibrations in the engine! Look carefully at that balancer! Don Link to comment Share on other sites More sharing options...
Guest Posted April 30, 2002 Share Posted April 30, 2002 I agree with Rice. A couple years ago the balancer on my 454 worked it self off the crank while I goin thru the gears. ( Me,stupid had put a wrong washer on it.) 2 weeks later lost all oil pressure on a 4000 mile engine. I never did connect the two problems til I read Rices post. Luckily I had no major damage. Better check that balancer. Fred. Link to comment Share on other sites More sharing options...
Guest Posted April 30, 2002 Share Posted April 30, 2002 I have a Fluidamper on it and although I did have my hands on it several times while under there and noticed nothing wrong. I will go back and check it. The engine is blueprinted and I never noticed any vibrations while on my 20,000 mi test run. I think that I installed it wrong because I found that the windage screen flange was under the nut, (stupid move) and may have not been lined up right for proper tightening. It is now mounted with the nut against the pump with the screen over it and then a lock nut on top of that. Oil pump is mounted with a stud. ------------------ George Lines Link to comment Share on other sites More sharing options...
Guest Posted May 22, 2002 Share Posted May 22, 2002 Fired it today. Have the headers open. I have what they call Scavenger headers on it. That is a 4-2-1 setup with the 2 part 2' long. Woke up the neighborhood in the afternoon. Left for something a short time later. There were 2 Sheriff cars parked down the street. My thought was that they were hoping to hear it start again so that they could locate it. My ears were ringing for about 2 hrs. This thing is exceptionally LOUD!!!!! Here is the bad part. After runing it for about 4 min with 60lbs cold oil pressure, I was satisfied with a job well done. WRONG!!! Underneath was a large puddle of oil. Back on the creaper for a look see. I remember having the main cap up and snugged down but had to remove it. STUPID ME!!!!! I had apparently slipped the rear seal out of it's slot so that it is half in and half out, or in the wrong grove. DDUUUHHH!!!! Now I have to remove the pan again!!!!!! ------------------ George Lines Link to comment Share on other sites More sharing options...
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