How to Break In Your Chevy Crate Engine in 8 Steps

Got a shiny new crate engine for your car? Congratulations!

The most important thing you can do for your car and your new crate engine is properly break in the engine. Ignoring this critical part of installing your new engine will likely wreck it, costing your sanity and tons of money.

If you’re looking for a step-by-step tutorial on properly breaking in your Chevy crate engine, you came to the right place.

8 Steps to Breaking in Your New Crate Engine

Step 1: Inspect Everything Under the Hood

Before starting the engine, check for any fluid leaks or damage. You can also use this time to top off any fluids your Chevy may need.

Step 2: Check the Oil Level & Prime the Oil System

Checking oil

Photo credit: Dvortygirl

This is a step you absolutely cannot miss. It’s likely that your engine has been sitting for a while, resulting in most of the lubrication draining back into the pan.

Ensure that there’s enough motor oil in the oil system. Even if you plan to use synthetic oil, you need to break in the engine with regular oil. Once the engine’s all broken in, you can make the switch.

Once you've ensured the engine has enough oil, install an oil pressure gauge and then disconnect the entire engine control system. Disconnect it in such a way that it cannot provide any ignition or fuel to the engine. Crank the engine with the starter for about ten seconds, and then check the oil pressure. If you don’t see any oil pressure, wait 30 seconds and then crank the engine again for ten seconds. Repeat until the gauge picks up the oil pressure.

Reconnect the engine control system and then start the engine. Listen for any strange noises and troubleshoot them until everything sounds fine.

Step 3: Adjust the Distributor Timing

Turn off the engine and let it cool down. When it’s cool to the touch, adjust the distributor timing by hand to ensure quick start-up and smooth idling.

Step 4: Set the Ignition Timing

Check your car’s service manual to find out where you should set it exactly. In general, most carbureted engines have their ignition timing at 10 degrees before top dead center with the vacuum advance disconnected. Most modern computer-controlled engines are usually set at 0 degrees before top dead center with the set timing connector disconnected.

Step 5: Break in the Camshaft (Flat Tappet Hydraulic Cams Only)

To do this, run the engine at no load between 2,000 and 2,500 RPMs for about 30 minutes.

Step 6: Drive Your Vehicle Around

Break in engine Vette

Photo credit: Valder137

At this point, it’s time to really break in the engine. What better way to do that than to put it to work? Take your ride out for a spin at varying speeds and loads on the engine for about 30 miles. However, make sure you avoid using a lot of throttle or running your engine at high RPM.

Step 7: Break in Your Piston Rings

While out on your drive, bring the engine up to 3,000 RPM and then coast back down to 20 MPH about five or six times. Next, bring it up to 5,000 RPM and then coast back down to 20 MPH a couple of times.

To play it safe, drive the next 500 miles without exceeding 5,000 RPM.

Step 8: Change the Oil and Filter

While doing this, inspect the oil and the oil filter carefully for any foreign particles. If you don’t find any, then your engine should be functioning properly.

A Few Things to Keep in Mind

Safety Tips

During the first five steps, take the following safety precautions:

  • Keep the emergency brake on.
  • Chock the wheels.
  • Make sure the transmission doesn’t fall into gear.

Oil Tips

  • If you’re planning on running synthetic oil, only use high-quality oil approved by GM. Look for oils that meet GM’s GM4718M specifications.
  • Watch your oil level like a hawk during the first thousand miles or so.
  • Use only high quality 10W-30 or 10W-40 oil during the break-in period

Do you have any more tips to share on breaking in a Chevy crate engine? If so, please share them on Facebook!