69 Chevy

I read this in another C3 Tech/Performance thread from a CF member who's been here a lot longer than me...What exactly gets washed out?

Does this 'washing out' happen to rod, main and cam bearings alike, or just one or the other? Would the rear main bearing suffer most because it is closest to the oil pump?

Since I have that range of oil pressure at 6-7K rpms in my mouse motor, and have for a few years now, with either 30wt or 10w-30 dino oil, if something were getting washed out wouldn't that increase my clearances and show up as lower oil pressure than before the washing out took place?

Is there something in the oil filter media that will be evident upon inspection if this phenomenon is happening in my engine?

If another member has pics of washed out bearings, I'd love to see them.

Mark Riles

I read that too and I was a bit puzzled by the statement. I've had those oil pressure readings on a lot of engines over the years and I do not think I have any recollection of it causing a problem or washing anything out. I'm looking forward to someone explaining that a little better and maybe tag some experiences along with it.

L88Plus

IMHO, that's an old wive's tale. I've never seen anything that I'd consider "washed out". The only bad things about too much oil pressure are the potential for leaks at plugs, etc. and the fact that it takes more grunt to turn the pump. Some of the Ford hi-po engines had over 100psi, don't recall bearing wash-out being a problem for those guys

1Fordman

That's an old term that came about when an engine was torn down and the rods and mains were into the copper layer. Oh look the tin and lead layers are gone so the bearings are "washed out"


No, they're probably worn out.

Mark Riles

Now that I have seen, but in my modest opinion I can't attribute the condition to oil pressure and I still don't think I have ever seen or witnessed damage to an engine because of moderately high pressures under 100 PSI regardless of what they call it.

Manuel Azevedo

You should have about 10lbs per 1000 rpms, so 60lbs or so at 6000rpms is just fine. I think I would like that oil pressure to wash any type of debris out that could be in my bearings! You do want volume of oil through your bearings and the pressure is built up when you push more oil through than can flow(pressure is developed) one item of pressure is to float the bearings. Sorry but that statement comes from someone that has no understanding of how it all works!!

MelWff

My 69 has a LT1(1970) short block with the stock LT1 pump. I normally get high readings in the 60 to 70 range either when cold or at high RPM's and have 10's of thousands of miles on the engine.

ajrothm

Another meaning for that term is when you get excessive fuel or coolant in the oil, thus causing bearing failure... Ie.. Washed out the bearings...

7T1vette

How much oil pressure is in the system means nothing to the bearings. It means that you need a bigger pump to generate that pressure and provide more flow (since higher pressure through the same amount of restriction will allow more flow) and the engine will use more fuel to produce that extra (and unnecessary) flow and pressure. Oil [like all other liquids] is incompressable; neither the oil nor the bearings care that there is more pressure in the system.

Ironcross

I would say that 'washed out' is another term for "Black bearing or just plain 'Dead......

Vette5.5

I've heard the term for wheel bearings, where water literally gets in, and washes the grease out. Happens probably even more on rear diff U-joints. Your best friend for monitoring engine bearings, is and undamped oil pressure gauge, as will start jumping around, when things are going bad.

wcsinx

That is how I always understood that terminology as well.

69 Chevy

Thanks for setting my troubled mind at ease, gents.

Ravoll

Maybe the term is a referance to "spinning" the bearings due to excessive oil pressure?Been there ,done that.

What most likely happens is that high RPM the HV pumps will suck a stock pan dry.Pump cavitates,oil pressure drops and ta da.....clackity clack.