How are you breaking in the engine? I ask because my build is going to be complete soon and I'm trying to figure out how to break it in properly!
The proper way to break in a new engine can be done in a variety of ways and almost everyone seems to have a different opinion. In the end it really depends on what you have done to the engine during the rebuild that dictates what exact procedure you use.
The most critical aspect is camshaft break in. This is only when you are using new or re-profiled (reground) camshafts. They must develop a acceptable wear pattern and have plenty of lubrication during break in. If not you can suffer premature cam lobe failure.
The next item is that the rings need to seat properly. This is really dependent on the proper hone grit and cross-hatch pattern. Modern rings typically seat very quickly. Some people still think their is a long break in for rings, this is only true when running hard chrome faced rings. These are almost non-existent in modern engines and even old engines that originally had chrome rings are best upgraded to a modern steel ring.
Here is a big myth, people for some reason think you need to 'break in' the bearings. Their is NO break in for bearings. Under correct operation the crank journals should never touch the bearings under any circumstance. Period.
Here is my procedure for breaking in a new engine. First make sure everything is in proper order, all hoses tight, oil in crankcase, cooling system filled, ignition system is hooked up correctly, fuel lines, etc..
First prime the engine using the diagnostic connector by jumping pins 7 and 14. This will activate the starter and turn over the engine without fuel or spark. This allows you to prime the engine with oil pressure, this part is important as you should never just fire up a dry engine, regardless of how much assembly lube you used. At this point you can prime the fuel pumps if you like by jumping the fuel pump relay. This is not really necessary, but can be helpful. At this point the engine is ready to start.
Here is the big moment, turn the key and it should start up like any engine old or new. Once the engine fires off let it catch and steady itself. You may hear some clattering from the lifters if they did not pump up all the way during the oil pressure priming, don't panic. Once engine speed has stabilized after the first few seconds, increase engine speed to a fast idle, about 1500-2000rpms. Hold it here and allow the engine to warm up to operating temperature. Having a friend, or assistant to help is a good thing. Check the engine for water leaks, oil leaks, watch the temp gauge. This is where a oil pressure gauge comes in handy also. After about 10-15 minutes at 2000 rpm your new camshaft if equipped should be broken in. Allow the engine to return to idle, check for leaks, top off coolant, etc. Turn the engine off and check the oil and coolant levels.
At this point take it out for her first maiden voyage. Drive the car through the gears bringing up the rpms then allowing the car to decelerate through the gears. This creates a high crankcase vacuum which helps pull any debris from the rings and cylinder hone out of the cylinders. After a few miles bring it home and change the oil. During the first 500 miles keep it off the rev-limiter and don't beat it up too much, but don't be scared to drive it either. After 500 miles, change the oil again and your ready to fully enjoy your new engine in any way you like.
Here are a couple notes, modern rings actually seat almost immediatly if they have the proper hone to the cylinder walls.
Obviously if you fire up a new engine and its stumbling, misfiring, making abnormal noises, leaking fluids or anything out of the ordinary, turn it off and fix the problems before continuing.
Thats about it, hope that helps,
Robert
Topic: It runs! :) (Read 3892 times)