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

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Originally Posted by tango

When you run your drill for 20min what do you think happens to the lifters ? And how will the rockers see oil if the lifters stay dry ?

I will say this again.
NEVER,NEVER TRY AND PUMP UP YOUR LIFTERS.
It's fine if you want to argue your point but I don't want other people on this forum betting bad information.
On page 278 of the Comp. cams catalog it say's in the very last paragraph.
"It is UNDESIRABLE to do as the lifters "pump up" lifters will cause the valves to open during the adjustment process,rather than positioning the valve lifter plunger in its operating position as it is supposed to do".
If you have questions at Comp cam their number is 1-800-999-0853.
On page 444 of Crane cams book it says.
"Many people mistakenly believe that hydraulic lifters must be soaked in oil overnight and be hand pumped up with a pushrod before installing into a new engine,however this is not necessary.
In fact,this could cause the lifter to act as a "solid" and prevent obtaining proper pre-load".
If you have questions call Crane cams at 904-258-6167.
Sometimes it is better to sit back and try to learn a thing or two on this forum.

Thnkas for the explanation Erik. I made the mistaske of pumping my lifters on my first small block build when I was 18..lucky for me nothing catastrophic happened. Always appretiate detailed explantions. Many on here listn and appretiate it.

Originally Posted by erik erikson

I will say this again.
NEVER,NEVER TRY AND PUMP UP YOUR LIFTERS.
It's fine if you want to argue your point but I don't want other people on this forum betting bad information.
On page 278 of the Comp. cams catalog it say's in the very last paragraph.
"It is UNDESIRABLE to do as the lifters "pump up" lifters will cause the valves to open during the adjustment process,rather than positioning the valve lifter plunger in its operating position as it is supposed to do".
If you have questions at Comp cam their number is 1-800-999-0853.
On page 444 of Crane cams book it says.
"Many people mistakenly believe that hydraulic lifters must be soaked in oil overnight and be hand pumped up with a pushrod before installing into a new engine,however this is not necessary.
In fact,this could cause the lifter to act as a "solid" and prevent obtaining proper pre-load".
If you have questions call Crane cams at 904-258-6167.
Sometimes it is better to sit back and try to learn a thing or two on this forum.

Originally Posted by 30-A Rider

Thnkas for the explanation Erik. I made the mistaske of pumping my lifters on my first small block build when I was 18..lucky for me nothing catastrophic happened. Always appretiate detailed explantions. Many on here listn and appretiate it.

Sometimes,I come off as a smart a$$ but I don't want to see people make mistakes that they can prevent.

The only lifter I have seen that recomends filling the lifter with fluid first is Rhodes lifters ,they are a fast bleed lifter ,meaning they will not pump up untill 3000 rpm is reached or there abouts.It takes very little force to depress the lifter cup when fully pumped up with oil,the rhodes lifters.
I will second the never ever pump up a regular lifter.

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.