yo

[Amir Yarkoni]

Hi im rebuilding an 86 5.7l small block

dumped the old heads (warped one) installed 2 Vortec heads ,   the motor that will see MARINE use,  48' house boat 3Bowee try hull.

my q is what is the purpose of the VALLEY COVERS in the engine ?

there was a very rusty cover held by 3 bolts that connected to a central oil delivery "

tube",    do I need it?   why is the cover used in the first place?  will its absence cause detrimental issues in the future? 

ps .aluminum intake manifold is new   how do I make sure proper install   I got rigid plastic intake gaskets   new grade 8 bolts from  local supplyer keep snaping at 25 foot/pd setting  help!

[Jsdirt]

Without seeing a picture, I can only guess. The only valley cover on a 5.7 is the intake manifold.

 

Sounds like an EGR tube - if so, that can be left out, BUT, we really need a picture. If that 3 bolt cover is down low on the right side of the engine, that's a cover for where an old school fuel pump  mounts. Those operate off a small rod that touches the camshaft. If there's a block off plate there, that means it was a fuel injected vehicle, but GM was still using up their stockpile of older blocks.

 

If you're snapping grade 8 bolts at 25 ft.lbs., your torque wrench is probably in dire need of calibration, or the gauge is damaged ... or, they're not grade 8 bolts.

[Doug_Scott]

The proper torque value of a fastener is also dependant on the size of the fastener.  Torque values also come in "inch/lbs" and can create breakage issues if they are mixed.