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would cam bearings cause lack of oil psi??? on my 97 sierra 5.7 litter v8? when its cold at start up i get over 40psi but has the engine warms up its drops down to about 20psi when idleing and then goes back up to 40ish my driveing is that the cam bearings or rod brearing that are causeing that? and how much would it be to reaplce each or those???

@seapeddler some Porsche’s did a needle bearing cam. So yea roller bearing

@themetalmaster007 its usually up

That is alot of work.

great video!!!!!!!!!!!!!!!!!!

It IS a big deal. The cam spins at half crank speed. I wouldn’t cal that ‘relatively slowly’ and it certainly carries an enormous load. Think of 16 400lb valvesprings pushing down, augmented by 1.76 ratio rockers, and trying to push the cam down and close off that oil hole on the bottom. This isn’t difficult guys, just read the shop manual.

Thank you! And, in response to upside down bearings, I prefer to float the cam w/hole at bottom rather than having the oilleat out from the top, All pressure on the cam is down, not up.

Thanx…

@DinosaurFan390
It’s not that big of a deal. A camshaft has almost no load on it and it spins relatively slowly.

so what is the correct alignment

A Real engine builder wouldn’t be throwing hammers into the crank saddles NOR would he be rolling cam journals on the crank bearing bores.

What a goon

I would like to add to this how important it is to have the cam bearing tool seated properly and securely in the bearing. Or when you go to hammer it will fold up the edge of the bearing or mushroom it.

kool

John, you are WRONG that is not the correct installation. As viewed from the front of the engine, the bearings in the 2,3,4, and 5 positions should have the oil hole at 3 o’ clock. The oil pressure is not strong enough to push up and out from under the valvespring pressure if the oil hole is straight down. You are way WAY wrong on this. Think about the hydrodynamic wedge, how is it supposed to form ? How many engines have you screwed up ?