Running in the engine
- Thread starter Chris Liokos
- Start date
I doubt that you will get only one answer here too, and I dont specialize in engines at all but this is generally what people do. Note that at first,it is the cam you want to pay attention too and generally you cam manufacturerwill have specific instructions
1. When you first run it, buy a proper break-in oil, not synthetic or your normal oil.
2.Start the engine, run at around 1500 rpm till it is warmed up or you notice something catastrophic is about to occur, if it is just something minor like a coolant leak, dont stop unless you absolutely have too. When the engine is warm, shut it down and let it cool.
3.Now i usually pull the valve covers and oil pan and recheck the bolt torque, change the oil to clean break-in oil, run it at 1500rpm again till warm and do some basic timing and idle adjustments.
4.Drive it, at first, do some hard acceleration and deceleration but keep the rpm above 1500 and below 4000, do that for as long as you can stand it. Then just drive it for about 500 miles but dont let it idle if possible and dont cruise at a constant rpm, always be either lighly accel or lightly decel (decel under engine breaking, not with the clutch in).
5. Change the oil again to a normal mineral oil, not a synthetic, and drive it for around 3500 miles (or whatever interval you change the oil normally) but again no idling and no redline pulls (yeah right, that one never lasts) but you can start driving it a bit more normally.
6.Change the oil to whatever you will be using and drive it like it is stolen.
That is how i do it.
1. When you first run it, buy a proper break-in oil, not synthetic or your normal oil.
2.Start the engine, run at around 1500 rpm till it is warmed up or you notice something catastrophic is about to occur, if it is just something minor like a coolant leak, dont stop unless you absolutely have too. When the engine is warm, shut it down and let it cool.
3.Now i usually pull the valve covers and oil pan and recheck the bolt torque, change the oil to clean break-in oil, run it at 1500rpm again till warm and do some basic timing and idle adjustments.
4.Drive it, at first, do some hard acceleration and deceleration but keep the rpm above 1500 and below 4000, do that for as long as you can stand it. Then just drive it for about 500 miles but dont let it idle if possible and dont cruise at a constant rpm, always be either lighly accel or lightly decel (decel under engine breaking, not with the clutch in).
5. Change the oil again to a normal mineral oil, not a synthetic, and drive it for around 3500 miles (or whatever interval you change the oil normally) but again no idling and no redline pulls (yeah right, that one never lasts) but you can start driving it a bit more normally.
6.Change the oil to whatever you will be using and drive it like it is stolen.
That is how i do it.
I've read a few good articles on this but don't have them bookmarked. The concensus seems to be that breaking in the engine and breaking in the cam are two different things. As I recall, the cam needs about 20 minutes of low-rpm running to be properly broken in. The engine really doesn't need thousands of low-stress miles as BMW would lead you to believe, and high revs in a new engine are not necessarily a bad thing. The most important thing is to seat the rings, which is best accomplished using high cylinder pressure, i.e., full throttle. Several pulls on an engine dyno are ideally suited to this task. The cam can be broken in at idle on a dyno while the airflows are balanced among the carbs (webers) or throttle bodies (stack EFI).
While we're at it, there is also a procedusre (see Carroll Smith's books) for breaking in the differential (if you have a new R&P gearset) and for bedding the brakes. /ubbthreads/images/graemlins/smile.gif
While we're at it, there is also a procedusre (see Carroll Smith's books) for breaking in the differential (if you have a new R&P gearset) and for bedding the brakes. /ubbthreads/images/graemlins/smile.gif
Howard Jones
Supporter
If I remember correctly Ford Motorsport wants their SVO motors run in as follows.
1 Set static timming and ballpart carb setting.
2 Start motor and warm up coolent, set timming right away, keeping engine at idle for only as long as necessary to set timming, idle speed, etc.
3 Run motor up to 2500RRpms for 30 mins.
4 Change oil and filter to your regular brand(s).
5 Drive as you will.
Note: I did mine this way except I have limmited my revs to 6000 until I have 30-40 hours on the motor then put in a 6700 PRM chip. I also changed oil and filter after 10 or 12 hours a second time just to make sure there is no junk in the oil from breaking in the cam chain. New cam(timming) chains tend to flake off material for the first few hours when new.
The main thing is to make sure any material in the oil is removed quickly once it is all been washed from the engine surfaces.
1 Set static timming and ballpart carb setting.
2 Start motor and warm up coolent, set timming right away, keeping engine at idle for only as long as necessary to set timming, idle speed, etc.
3 Run motor up to 2500RRpms for 30 mins.
4 Change oil and filter to your regular brand(s).
5 Drive as you will.
Note: I did mine this way except I have limmited my revs to 6000 until I have 30-40 hours on the motor then put in a 6700 PRM chip. I also changed oil and filter after 10 or 12 hours a second time just to make sure there is no junk in the oil from breaking in the cam chain. New cam(timming) chains tend to flake off material for the first few hours when new.
The main thing is to make sure any material in the oil is removed quickly once it is all been washed from the engine surfaces.
Howard has the right idea. When first starting the engine you need to take it up to 2500rpm asap and hold it for 30 min. this gets enough oil flow on the cam lobes to break them in. Check coolant and all during this period. a house fan can come in use to help take away that extra heat on the headers and such , since it is sitting still. By this time your rings should be seated in fairly well. Then go the drive it like you stole it route to engine break in some people believe in (I dont) or go easy on it for awhile. regards Dan
As far as the cam goes, the advice already given to break it in for 20 to 25 minutes is correct for flat tappet cams. For roller cams, you want to bring the RPMs up enough to get good oil pressure to the engine right away, but beyond that you don’t really need to do anything special.
As for the rings, the best thing is to ask the tech people from the company that made the rings. If for some reason you cannot do that or cannot get a useful answer from them, here is a procedure that has been used for racing engines in both cars and motorcycles for many years. It is based on the fact that there are two conflicting problems when braking in rings.
1. The rings need high cylinder pressures to push them against the walls hard enough to wear in and seat properly. (You can drive for hundreds of miles at low power levels and never get the rings properly seated – it takes pressure.)
2. Because the rings are not yet well seated, they cannot transfer heat very effectively from the piston to the cylinder walls and can be damaged by too much heat caused by holding full throttle for more than a short period of time.
The procedure is as follows:
Once you have completed any necessary cam break in, you find a long, clear stretch of road and put the car in a fairly high gear (3rd or 4th). Starting from a low speed, you accelerate at full throttle for 10 seconds. That will give you the high cylinder pressures and varied RPMs necessary to seat the rings.
After the 10 seconds you lift your foot completely off of the gas and coast for 1 minute. This gives the rings time to transfer the heat without being damaged. When the 1 minute is done, you accelerate at full throttle for another 10 seconds then give the rings another minute to cool down. Repeat this 10 times and the rings should be well seated and ready to use normally.
As for the rings, the best thing is to ask the tech people from the company that made the rings. If for some reason you cannot do that or cannot get a useful answer from them, here is a procedure that has been used for racing engines in both cars and motorcycles for many years. It is based on the fact that there are two conflicting problems when braking in rings.
1. The rings need high cylinder pressures to push them against the walls hard enough to wear in and seat properly. (You can drive for hundreds of miles at low power levels and never get the rings properly seated – it takes pressure.)
2. Because the rings are not yet well seated, they cannot transfer heat very effectively from the piston to the cylinder walls and can be damaged by too much heat caused by holding full throttle for more than a short period of time.
The procedure is as follows:
Once you have completed any necessary cam break in, you find a long, clear stretch of road and put the car in a fairly high gear (3rd or 4th). Starting from a low speed, you accelerate at full throttle for 10 seconds. That will give you the high cylinder pressures and varied RPMs necessary to seat the rings.
After the 10 seconds you lift your foot completely off of the gas and coast for 1 minute. This gives the rings time to transfer the heat without being damaged. When the 1 minute is done, you accelerate at full throttle for another 10 seconds then give the rings another minute to cool down. Repeat this 10 times and the rings should be well seated and ready to use normally.
Paul Thompson 'Hooligan'
Admin
Hmmm - that road better be not only straight but steep too, 10 seconds at full throttle in 3rd or 4th would leave me bouncing off the rev limiter repeatedly.... I read that you mean let it rev to max normal safe rpm as opposed a fixed time. /ubbthreads/images/graemlins/grin.gif
That's the reason for 3rd or 4th gear. If you start from a low speed (20 - 30 mph) you will not over rev in 10 seconds. (Top speed in 4th should be at least 150 mph. You won't get anywhere near that pulling a high gear for 10 seconds).
This does become more difficult the faster the car is. You need a track or a long (1/2 mile minimum), unused section of road. (no cops would be a real good idea too).
This does become more difficult the faster the car is. You need a track or a long (1/2 mile minimum), unused section of road. (no cops would be a real good idea too).
I have a friend who had his Porsche engine rebuilt in Oregon - he lives in Monterey. He flew up to Oregon to drive it back. I think he was going to a track event at Thunder Hill and didn't have time to get it broken in properly, except on the drive down. So he did it on Highway 5. He got a speeding ticket in Oregon as I recall, and said the other people on the road probaly thought he was some idiot sports car driver as he zoomed past them at a high rate of speed (over 100 MPH) and then slowed down, only to speed up again soon thereafter...
I had my engine run in on the dyno, but it probably still ended up costing more than a speeding ticket /ubbthreads/images/graemlins/smile.gif
I had my engine run in on the dyno, but it probably still ended up costing more than a speeding ticket /ubbthreads/images/graemlins/smile.gif
