The reason to prelube before you turn the crank is to make sure you get oil to all the bearings prior to turning anything, last thing you want to happen in a new motor is turn it metal to metal...
Quote straight from Gm...
1) Safety first !!! If the car is on the ground, be sure the emergency brake is set, the wheels are chocked, and the transmission cannot fall into gear.
2) Be sure to check the oil level in the engine and prime (GM#12368084, see bottom of page) the oil system.
3) Run the engine between 2,000 and 2,500 RPM, with no-load on the engine for the first 30 minutes.
4) Adjust the distributor timing roughly by hand for a quick start up and smoothest idle possible.
5) Adjust the carburetor settings, if necessary.
6) After the first 30 minutes of the engine running, set the ignition timing to proper timing specifications.
7) Drive the vehicle with varying speeds and load on the engine for the first 30 miles. Be sure not to use a lot of throttle or high RPM !!!
8) Run five or six medium-throttle accelerations to about 5,000 RPM (55 or 60 MPH), then let off in gear and coasting back down to 20 MPH.
9) Run a couple hard-throttle accelerations to about 5,000 RPM (55 or 60 MPH), then let off in gear and coasting back down to 20 MPH.
10) Change the oil and filter with 10W30SG oil and PF1218 AC Delco oil filter GM#25160561.
11) Drive the next 500 miles normally, without high RPM's (below 5,000 RPM), hard use, or extended periods of high loading.
12) Change the oil and filter again.
13) Your engine is now ready for many happy cruising miles !!!
GM# 12368084
12368084 - Engine Oil Primer Pace Price $29.95
This engine oil primer tool is used on all V6 and V8 Chevy engines. This is the sure way to get oil to those bearings before you start that new or rebuilt engine.
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Eagle86K5
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