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Old 07-17-2008, 07:59 AM
eldoradoboy eldoradoboy is offline
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I would say that even a good filter will miss quite a bit of smaller particles.. and that van is heavy enough that it is working the engine at low RPMS to get it up to speed.. and I'll bet its not taching very high out on the road either....

ive come to the conclusion that I got a CRAP engine for my monte carlo.. its coming out to go to a machine shop for teardown as I dont have the extensive knowledge to tell where my excessive valve train noise comes from..

but I do know that when I drained the oil pan I could see what looks like very slight metallic swirls in the oil so I know there is serious mechanical damage going on...

Also oil PRESSURE isnt everything.. im gonna venture to say that the dash gauge Port on this engine is right back by the oil filter.. so what you are getting is a pressure reading right off the oil pump.. all that says is that the pressure at that point is proper.. doesnt mean you dont have an oiling problem farther along in the oil circuit... and most likely that engine being thrown together like it was probably had pretty loose tolerances.. that once the wear starts creates even looser tolerances... a HV oil pump does just that pumps a lot of oil and in doing so builds up pressure..

but think of this analogy.. if you could put a pressure gauge on your garden hose and turn on the water.. you can cover up the end of the hose with your thumb and the water will just trickle out.. but the pressure would still read high.. uncover a little more of the hose and the pressure may ver ywell stay the same but you will have more water flowing because the hose and the water source (your well pump or city water as it may be) can handle the volume you are flowing.. take your thumb off altogether and you'd see a pressure drop but have Lots of water flowing..

pressure builds up as a result of a restriction thats just a fact of physics.. so the PLAN is that the restriction in an engine that creates pressure is the bearings / lifters themselves.. but if the tolerances are too loose you would see a drop in oil pressure.. so most install a HV (high volume) pump.. and get that feel good feeling because the dash gauge reads 55 on the highway 40 at idle... thats great as long as the pressure is really the bearings.. but what if you are just pressurizing against the oil gallerys themselves.. the passages are only so big in an engine.. with these worn out bearings the tolerances wouldve gone to heck in a handbasket and oil should just Flow out.. causing a reduction in pressure.. yet the gauge pressure didnt show any drop... so i think we have a classic oil starved motor here.. shoddy work gone bad that causes a compounded issue then of oil starvation at the bearings....

so one could say the lifters should rattle.. however it doesnt take much oil pressure to pump the lifters up.. lifters will stay quiet at 5 PSI.. or perhaps the lifter gallery passages were fine and tis just the main / crank oiling that was bad..

my main point here is a couple things.
1] just because the pressure at the gauge sender is high doesnt mean we have oil everywhere..

2] I wouldve certainly thought we would see some kind of oil pressure changes with worn out bearings like these.. we have bearings that have had to add .005 - .010 or more in tolerance to the journals... thats a lot of area for oil to flow through and reduce pressure...

-Christopher
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