Hey guys.... (my other screenname is pegleg71)
I'll be getting my freshly rebuilt 333 back in a couple weeks and I had a question about the break in procedure. First of all everything is either new or gone through. The cam is a new one too, so that will need to be broken in. Anyway.... I was just wondering what the break in procedure is for a fresh engine? Once it is in the car should I just treat it as a cam break in? The rings will be broken in by the time the cam is right? Is there a certain break in procedure for rings, or anything that I should pay particular attention to that I might not be realizing?

Last question....how long/many miles should I wait before I start driving the car hard? I've heard that you should keep it below 4,000rpm for the first 1000 miles?? :confused: That just sounds wrong to me though. Well any advice would be greatly appreciated. smile.gif

Thanks in advance smile.gif

After I break in the cam on a new engine, I usually take the car out for some sprints down an open road.

First I do an oil change and check to make sure the cam break in went well.

Then I make sure the timing/floats/pressure/valves are good.

Then I'll start out giving it 1/4-1/2 gas up to 3000 RPM (doesn't take long)...

Then I'll give it 1/2-3/4 throttle to 4000 RPM...

Then I'll give it 3/4-full throttle to 5000 RPM.

I've been told to do this under load (3rd gear), but I just make sure the tires don't spin.

Then I do an oil change again.

After that I drive it like a grandma for 500 miles.

I've been told it helps seal the rings better. I've always done it and had no problems. I'm sure others will disagree though.

I just got my 331 broke in a few weeks ago. Man, I was a nervous wreck. I rebuilt the thing from the ground up and I was so worried that i would somehow wipe out the cam. I think i read every post in this forum and the Monte Carlo forum and the camaro forums and then I called Lunati Tech Support and talked to them ( It was a Lunati cam).

They recommended the following and it pretty much jives with the knowledge base in this and the other forums.

1. Make sure all the fluids are correct levels. Use straight 30 weight oil, not synthetic or muti-grade. Some say use EOS from GM as an oil suppliment, some say not.

1b. Use a 50/50 water glycol mix, not just straight water as your engine temps may get very hot during the break-in. You need the extra protection.

1c. Use a thermostat and drill two small holes in it to let the air out and make sure to get it as full as possible. You don't want the water pump to air lock.

1d. Don't run high pressure springs on the break-in. If you have double valve springs, take the inner spring out.

2. Get the number 1 piston to TDC on the compression stroke.

3. Use a drill and an old HEI body with the gear removed and run the drill until you have oil coming out of all of the pushrods.

4. Rotate the engine 90 crank degrees by hand(no starter) and repeat the prelube step with the drill. Repeat the 90 degree rotation and prelube until you have the #1 piston back up on compression stroke.

5. Set the timing mark on 10 degrees advanced.

6. Now install the distributor so that the rotor lines up with #1 spark plug.

7. Check oil level again and make sure it is good.

8. Get a friend to help you watch the engine while you run the throttle and watch the gauges and tach. You really need to install temporary gauges and tach if they are not already in your car.

9. Make sure the carb is primed before you start it. You don't want to be cranking the engine for minutes while the fuel starts to prime.

10. Fire it up and immediately watch for the oil pressure to come up. As soon as you see it come up, run the RPM's up to 3000 for the first 5 minutes ( Lunati recommended 3000, many others said 2500).

11. Theres goin to be alot of smoke if the engine and headers are newly painted. This is where your buddy comes in handy to watch the engine very closely. Immediately on startup and shortly thereafter, make sure the cooling water is circulating, or you will shortly have an overheat on your hands. The smoke will clear out in the first 5 minutes.

12. After the first 5 minutes, drop the engine RPM's to 2500 and then vary between 2000 and 2500 rpm for the next 15 minutes. (this was recommended by Lunati) Just continuously vary the throttle and hold it between 200 and 2500.

13. After the break-in, drain the oil and cut the filter open to inspect for metal flakes. Don't get too concerned with a few flakes, thats going to happen,. What you don't want is metal flakes covering the whole filter element. Also, don't freak when you see the oil after you drain it. It will most likely look like crap. Mine was black as could be and had a shimery appearance. I got worried at first but then i remembered the black Lunati cam break-in grease that has some level of soft metal to assist in the cam break-in. The initial ring blow-by as the rings are seating in will also blacken the oil.

Now is where the methods begin to deviate. They are all over the spectrum, from change the oil every 50 or 100 miles for a while to take it to the track and flog the crap out of it. In any case, change it again within at least the first 500 miles.

If you have to shut it down during the break-in process, then do so. The break-in is cummulative, so fix your problem and then go right back where you left off.


Now all that being said, when i rebuilt my first 3 engines (all stock), I installed used lifters on a used cam and mixed them up. I used regular oil on the cam, no pre-lube. I preprimed the motor without going through the 90 degree rotations and started it up and didn't put it through the break-in process. They all ran just fine. Maybe I was lucky or maybe this is all overkill. You have to decide that. I'm sure this last paragraph will encite many people and that was not the intent, I'm merely pointing out that I have done both extremes with the same result, good running engines.

Hope this helps,
Clyde

What is the purpose of 1C? You kinda lost me there? Is that so I can get the proper amount of coolant into the engine? Otherwise if I just fill up the radiator and start the break in procedure then that won't be even close to enough coolant right?

Sounds good. I don't have the means to run just the outer springs for this break in though. Do you think it'll be a problem running my double spring setup? I wouldn't think so personally. Don't have an old HEI body either. As far as the rest though it sounds good. I'd rather put a little extra time into it to make sure. Already had an engine that ate two cams and needed to be rebuilt. That's what's going in now. Wouldn't I be able to use a really long flat head screw driver to turn the pump to pre-lube the engine? How else could I prelube the engine without having an old HEI body? I was told to just pour a little gas in the carb to prime it....is this correct? Sorry about all the questions.

Thanks a million for the replies. smile.gif

Also, i'll need to replace the thermostat after the break in right? Do you guys recommend a certain temp thermo? Otherwise i'll just use a 180. Thanks again.

Originally posted by 71chevy0192:
What is the purpose of 1C? You kinda lost me there? Is that so I can get the proper amount of coolant into the engine? Otherwise if I just fill up the radiator and start the break in procedure then that won't be even close to enough coolant right?

Sounds good. I don't have the means to run just the outer springs for this break in though. Do you think it'll be a problem running my double spring setup? I wouldn't think so personally. Don't have an old HEI body either. As far as the rest though it sounds good. I'd rather put a little extra time into it to make sure. Already had an engine that ate two cams and needed to be rebuilt. That's what's going in now. Wouldn't I be able to use a really long flat head screw driver to turn the pump to pre-lube the engine? How else could I prelube the engine without having an old HEI body? I was told to just pour a little gas in the carb to prime it....is this correct? Sorry about all the questions.

Thanks a million for the replies. smile.gif ==
Yes, 1C is so you do not have an air lock, it lets the air escape from under the thermostat & you do not have to replace it after break in, it will work fine.
You really should break in the cam with just the outers if you have double springs.
People get away without it but others don't.
A tool to remove the springs is very cheap & making or buying a fitting to put air in the cylinder is pretty easy. It can also be done with some small hose put into the cylinder to hold the valves up.
No real reason you can't do it.
You can make a pre oiler out of any old distributor or you can buy one but a screwdriver ain't going to make it ;)
You need the housing to complete the oil passages to the lifter galleys
Pour the fuel into the vents with a small funnel if it's a holley & it will fill the bowls.

when changing springs you can also use a piece of clean rope. shove it in the spark plug hole and turn the motor by hand unitl the piston shoves the rope up against the valves. this will keep the valves from opening.

even tho the spring compressor tool is cheap.....i have when in a pinch use a open end boxed end wrench to compress the retainer to remove the keepers.......put a nut on the rocker stud and use a wrench the same size of the nut and slid it past the nut and use the wrench as a prying tool to push the retainer down. use a magnet to extract the keepers.

I've made my own plug adapters for applying air pressure a few times by welding an airnipple to an old sparkplug body----free. I've also done the spring changes with nothing but the pc oil seals holding the valve up. If your carb is new I would definately test it out and pre adjust it on a friends car to make sure it's in the ballpark and will run good enough for cam break in at minimum. Things like float adjustments etc. are not what you want to be doing during the first 20 minutes of run time- you want this thing to fire up and run at 2000-2500 rpms for the first 15-20 minutes. After that you can dial in the carb and timing etc. Run the outer springs only, no sense in chancing a cam failure after all of this work and money. :(

Yeah, you guys are right about the springs. I have the tool I need and can borrow a compressor. I like the idea of sliding rope for example into the cylinder and using it to hold up the valves when the piston is pushing on it. (nice to know they can't fall down) I'm just always afraid that i'll drop a retainer or something down in the engine. Should I tag/mark/bag the springs so I know which valve each spring came from when I took them off? or does it not matter? I think i'll have the guy who is building the engine take the 2nd springs (the inside stiffer ones) off when he's putting it together and set the valves with just the outer springs. That way I figure i'll have to pull the springs one less time myself, and that'll be one less time that it'll have to be done when the heads are on the engine. Using only the outer springs (on Performer RPM heads) will be fine for the break in then? I mean the outer springs aren't weaker than others given that the head setup is for double springs?

Just a couple more questions...thanks for bearing with me if you're still reading. :D Since i'll want to adjust the valves again after going through the break in, would it be ok if I just put a minimual amount of miles on the car with only the outer springs on the heads? I figure when I adjust the valves again (after the breakin and a little bit of driving) i'll just replace the 2nd springs during that....just to save a little work and keep from having to pull the valve covers yet again. I hope that made sense.

Last question....
I won't have a running car to test my carb on, so is there a way I can set it when it's off the car so I know it'll be alright for the break in? Like baddbob71 said I want to make sure the car is running at least decently when breaking in the cam so that there are no (or fewer) complications.

Thank you very much for your help everyone :D graemlins/thumbsup.gif

as far as the carb goes i think most poeple here are concerned weather the carb is a carb that has been sitting for some time with out use...........like a holley that has sit for months or years with out a rebuild because they will give you all kinds of problems since the cheap cork gaskets shrink and creat alot of problems........

if the carb has been rebuilt and the gaskets are fresh and floats set pretty close by eye site(level) and the idle mixture screws are at least 2 turns out it would be just fine........at 2000-2500 rpms you are strictly running off the jets and not the idle circuit...........

you just dont want to throw a carb on that you have no idea what it looks like inside.........as long as the gaskets are good and the jets are close to factory settings and you have a few turns out on the mixture screws and the floats are at least set level with the bowl then it would be fine for a break in period.........

pour some fuel down the vent tube using a piece of paper as a small funnel. and give the throttle a few yanks back to make sure you have a fuel squirting out the squiters.........

set the timming mark on the hormonic to 12 degrees before tdc and turn the dist. to were the rotor is pointing dead on the #1 post of the cap and snug the dist. down alittle. so that way your motor is at least set up in the ball park.

About the only thing that I would like to add is that I prefer to use water only as a coolant during the break-in. That way, if there are any leaks it won't be a big mess.

As far as how to treat the engine once the cam break in is complete, I took the car for about a 100 mile local highway/freeway trip (light traffic) before I really got on it. By the time I had 400 miles on it I had already "dusted" a Formula Firebird.

Mike

Unclepennybags - Looks like we are running very similiar engines.

ddeennis - The carb is a Edelbrock 600cfm electric choke. I think that part # is 1406. It's been sitting for about a year now, and is only about 3 years old. (never took it off the intake when I took the engine apart) I remember that I messed with the fuel mixture (not knowing what I was doing) while the car was running, so i'm sure that both sides aren't even set the same. Should I screw the two screws all the way back in and then just turn them out two rotations? I'm not sure how the floats are set, or even where they are on the carb to be honest....I don't know much about carbs. redface.gif Can you tell me where to look for this on the carb? I don't think the jets have been changed on the carb, should be stock. What do you think I should do given the situation?
Thanks again smile.gif