Things to check after the engine is running

Lockhart Machine

engine is running
offers the following checklist of questions and suggestions to be asked before the first engine start up on a fresh rebuilt engine.Using these materials will provide useful information to an installer, so they can deliver a vehicle that will provide long life and good performance.

Have things ready:

on gas engines, have the timing light hooked up and ready

  • 1
    As soon as the engine starts up, set the ignition timing and then plug the vacuum lines in and rev it up to 2000 RPM
  • 2
    Follow start-up instructions, do not idle engine!
  • 3
    After 20 minutes is the engine valve train quiet? (Most engines take a few minutes to quiet down)
  • 4
    What is the vacuum and engine RPM?
  • 5
    Double check the ignition timing.
  • 6
    Are there any gasoline, coolant or oil leaks? Stop the engine and fix it.


Be sure to address any problems as soon as they happen.

It does not hurt to shut the engine off, fix the problem and restart.

The first few minutes of running is the lifeblood of all rebuilt engines and care should be taken to guarantee long life.

More things to check-

It’s usually a good idea to have more than one person to share responsibilities. e.g. one person on the key, another on fuel and a third on timing and coolant.

  • 7
    Check coolant temperatures and oil pressures OFTEN!
  • 8
    Is the charging system working? Real important on cars with an ECU.
  • 9
    Did the coolant level drop? Top it off with the correct 50/50 coolant mixture and don’t just add water to the radiator.
  • 10
    Do you have glowing cherry red exhaust manifolds? Advancing the ignition timing should cool off the exhaust gas temperature. Check for vacuum leaks.
  • 11
    What is the RPM and hot oil pressure after running for a total time of 20 or 30 minutes? Break–in could be done in 10–minute segments at a time adding up to a total of 30 minutes. This allows the camshaft and flat lifter to break in properly.
  • 12
    What is the total mechanical ignition timing with the vacuum advance unhooked? If not within specifications, repair before driving vehicle.
  • 13
    Does the vacuum advance (if equipped) function properly and is it connected to the correct port? Improper ignition advance causes drivability and engine problems.
  • 14
    Is the EGR (exhaust gas recirculation) working properly? The EGR system cools the combustion chamber by changing the air/fuel ratio. The added EGR displaces air which richens the air to fuel ratio and eliminates pinging.
  • 15
    If everything checks out good, the Lockhart Machine rebuilt engine is now completely broken-in and ready, willing, and able for you to take it out and “stomp” on it.
  • Note:
    This information is provided from the best available sources. However, Lockhart Machine does not assume responsibility for data accuracy or consequences of its application.