Rebuilt engine start up pros & cons

I

iddie makel

Active Member
Hello Everyone,
When I start up my rebuilt engine for the first time,is it necessary to immediately hit the road at a specified speed,or can I shut it back down to look for leaks etc.
The reason I ask is because I have heard that the engine must be run at a certain speed to ensure that the rings "seal" properly,and I've also heard that people with rebuilt engines should just drive normally.Please give me your thoughts.Thank you.
iddie :confused:
 
They used to suggest that you run at one speed, but the general conscensus now is to vary the speed. The method I have used for years is to drive the car at a high enough rpm to see a rise in the temp gauge, and then back down and let it cool for a bit. You actually get a better break in if you allow the engine to expand and contract normally.

Everyone has their own method, and they all work ,as long as you use common sense and do not beat on a fresh engine.
 
Just prior to starting up a engine after rebuild, I remove the distributor and, using a special tool and electric drill, spin the oil pump until pressure is seen at the oil pressure gage and for a few minutes afterward.

After you confirm you have sufficient oil pressure, reinstall the dizzy and set the timing to ensure the engine will start right up as soon as it turns over. The engine should then be run at a speed of 2000 RPM for a period of 20 minutes, to break in the can and prevent scoring. My son-in-law is a valve train Engineer for Delphi and confirmed that is standard procedure for automotive engines.

After the cam break-in procedure, I drive the car, varying the speed & RPM range for the first several hundred miles, but staying below 3000 RPM. I initially change the oil & filter after the first 500 miles and then after every 3000 miles. I've followed this practice for the 40+ years I've rebuilt engines and have never had a problem.
-Bob
 
Hello to theoldguy & 55Spcl,
Thank you very much for your fast and informative replies.I will definitely use common sense.I just hope the engine starts when I try to fire it up.I'm a little leery of pulling the distributor back out,but understand the need to get oil pressure.How large of a drill will I need to spin the oil pump?
Thanks again.
iddie
 
I use an old 1/2" drill motor. Not sure what the HP is, but it doesn't take too much too spin the oil pump. 3/8" drive drill motor should do the trick.

After you get pressure in the system, replace your dizzy, making sure you're on the timing mark with #1 cylinder at TDC on the compression stroke (i.e. both rocker arms loose - it's real easy to be 180° off!!). Set your rotor to be coming up on #1 spark plug lead by turning the diszzy until the points are JUST starting to open, using a continuity light. If everything is set correctly, the engine should fire up immediately, which is what you want to happen.
-Bob
 
Hello 55Spcl,
I think I really screwed up by not priming before I reinstalled the engine.I'm going to have to read up on the continuity light.I understand what you're saying,but I've never done it.I'm going to try.Thank you very much.
(neandertal}
 
Rather than a light, I just use my ohm meter with a set of clips. The light is great, but I never have one... :(
 
Hello bob,
How do I hook up the ohm meter?Also,is there a trick to getting the distributor back in exactly as I take it out?Thanks for helping me.

Iddie aka neandertal
 
Do as described above to locate the crankshaft timing mark on tdc firing stroke. See where you want no. 1 plug located when the timing is done. The distributor rotates a little clockwise when it goes in. In order to get it where you want, you will have to turn the rotor assembly counterclockwise from where you want it to end up. It's often easier to replace the rotor when doing this.

Your oil pump drive will probably not be lined up and the dist. will just drop into the drive gear a little and stop. Pull the distributor and note about where the drive should be on the distributor. Look into the block and rotate the oil pump drive with a screw driver to about where you think it should be. Repeat this process until the dist. drops properly into place. Lightly secure the dist. so that it can be rotated.

Rotate the dist. housing counterclockwise past where no.1 should be. Here you can use a light as described above or an ohm meter. Set the ohm meter to resistance. Connect one side to each side of the points while they are closed and should be coming to number one firing. rotate the dist. until they begin to open, you will see the loss of connection on your meter.

Snug the distributor a little more, and hook up your timing light. Start the engine and set the timing.

Did I miss anything???
 
Thanks again bob,
I'm going to try to do this,it's going to take a while though because this is my "maiden cruise".
iddie
 
You must log in or register to reply here.
Back
Top