Thread: About to fire up a BBC for break-in, any tips?

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Ok so I'm down to the check list. I've got a '66 402 that's about to be started. Most likely this weekend. Fan shroud still needs to be modified to clear the march serpentine pullies and all the fluids need to be filled. That and the 2 year old gas needs to be drained out of the tank Yep, it's been that long. After that I'm going to prime the engine set the distributor back in... and turn the distributor til it fires?? Or is there a better way to get it timed before you start it?? It's got a solid lifter cam, and a mechanical advance Mallory Unilite distributor, if that helps. Any advice would be appreciated.

i am assuming you will have the #1 cylinder at top dead center befor dropping the distributor back in, if not you need to do so. then when it seats the distributor rotor needs to be pointing at #1 pin on your cap, thats a good starting point.

Originally Posted by mooneye777

i am assuming you will have the #1 cylinder at top dead center befor dropping the distributor back in, if not you need to do so. then when it seats the distributor rotor needs to be pointing at #1 pin on your cap, thats a good starting point.

Like mooneye says, make sure your on tdc.
I would prime it a min. of 20 min.
Make sure you have oil coming out of most of your rocker arms.

Originally Posted by erik erikson

Like mooneye says, make sure your on tdc.
I would prime it a min. of 20 min.
Make sure you have oil coming out of most of your rocker arms.

Most? Should see oil at all of them shouldnt he?

Originally Posted by 65cayne

Most? Should see oil at all of them shouldnt he?

2 TO 3 MIN Is long enough to prime your engine . Have some one look at the oil pressuse gauge when you are priming it . it sould go up to were the pump is set 60psi or more . Then it is ready to start .

Originally Posted by tango

2 TO 3 MIN Is long enough to prime your engine . Have some one look at the oil pressuse gauge when you are priming it . it sould go up to were the pump is set 60psi or more . Then it is ready to start .

2 to 3 min ??
You won't even get oil at half of the roller rocker arms in two to three min.

I know about putting it to top dead center and all that. But I recall Denny talking about a method of timing it before you start the engine? Thanks Eric I didn't know you were supposed to prime the engine for that long. Any other good tips?

Originally Posted by 69elko

I know about putting it to top dead center and all that. But I recall Denny talking about a method of timing it before you start the engine? Thanks Eric I didn't know you were supposed to prime the engine for that long. Any other good tips?

Yes,if it is a hyd. cam or a solid lift cam dump a can of Comp cam camshaft break in lube a can of GM'S E.O.S. if you can find it.
I would also "prime" the carb to begin with, then say about 20 hail Mary's!!.
I was just kidding about the hail Mary's.

Remove the thermostat fill the block up all the way with coolant with the lower radiator hose installed . Then reinstall the thermostat housing and upper hose . Top off the radiator and run a 10lb cap . This will help to keep your engine from over heating . By filling the block there will be no air pockets . Now you can run your engine 1600rpm for 15 min to break in your cam . When you first start it check good for any leaks . If you had a carb that you know worked good run it for now . This way you sould not have any problems keeping the engine running .

Originally Posted by tango

Remove the thermostat fill the block up all the way with coolant with the lower radiator hose installed . Then reinstall the thermostat housing and upper hose . Top off the radiator and run a 10lb cap . This will help to keep your engine from over heating . By filling the block there will be no air pockets . Now you can run your engine 1600rpm for 15 min to break in your cam . When you first start it check good for any leaks . If you had a carb that you know worked good run it for now . This way you sould not have any problems keeping the engine running .

I.M.O,1600 rpm's is not enough.
I would run at 2,000 rpm,'s or more for cam break-in.

When you prime it should you turn the engine over manually to open up all oil passages?

I've got the EOS in the engine, and actually was going to check Courtesy Chevrolet and see if they had any more, I heard it was discontinued. I ordered some break in racing oil through Isky that's supposed to be high on zinc though for when I run out of EOS. Expensive though, like $6 a quart. Thanks guys. Looks like it won't be started this weekend though. It's pouring outside and I managed to break the carbon piece inside the distributor cap when installing the engine. Guess that's what you get for not having someone help you when putting the engine and tranny in.

Erik,

I understand the issue of not pumping up the lifters. Here's a question, though. Assuming that all of the rockers are loose, and the adjustment will be zero lash + 1/2 turn, what difference does it make whether the lifters are pumped up or not?

No argument - just a question.

Note: I use the recommended method of adjusting: Intake almost closed, adjust exhaust; exhaust just opening, adjust intake. I tighten the poly-locks until there is no slack, then a half turn.

Originally Posted by Henry Rifle

Erik,

I understand the issue of not pumping up the lifters. Here's a question, though. Assuming that all of the rockers are loose, and the adjustment will be zero lash + 1/2 turn, what difference does it make whether the lifters are pumped up or not?

No argument - just a question.

Note: I use the recommended method of adjusting: Intake almost closed, adjust exhaust; exhaust just opening, adjust intake. I tighten the poly-locks until there is no slack, then a half turn.

It does not make a difference.
If I have already installed the cam and lifters my next step will be to figure out what length push-rods I am going to run.
I will "mock-up" a length checking push rod and roll the engine over and check my "pattern" on the valve stem if all looks good then I will measure the length of the push rod checking tool and find the right length push rods and install them.
Then I will adjust the rocker arms one at a time in the same way you described above.
For stock rebuilds I will use 1/2 to 3/4 pre-load.
If I know he will be racing of thinks the engine will see over 5,000 rpms I then will only run a 1/4 pre-load.
When I build an engine the very last thing I do is fill the engine with oil to "prime it".
So to answer your question it does not make a difference that is the last thing I do to an engine before I ship it or the customer takes it home.