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Discussion Starter #1
I'm getting ready to fire up a motor that was built maybe 20 years ago. I've primed it and adjusted valve lash and of course have break in oil (Driven BR 15w-50 Racing break in oil) so it should be ready to go. Over the years I've rotated it many times but it is an old cam with hydraulic flat tappet lifters.
What I remember from years ago was to run it at 2000rpm for 20 minutes or so. Am I correct about this? Any other suggestion from some old school engine guys are very welcome because I'd hate for things to go bad and have to pull it out again. I know I'm taking a risk but it's all I have to work with at the moment.
What am I missing, Jim
 

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How radical is the cam?
Back then the steel was good, the key will be to insure it fires right now when you turn the key, prelude with a 1/2 inch drill and insure you see oil at every rocker arm, then stab the distributor in at 10 degrees advanced, fill the fuel bowls, give it 4 pumps and hope it starts.

Keep it between 2,000 and 2,500 for closer to 30 minutes varying the rpm by 200 up and down every few minutes, shut it off and change the oil, fill with the same oil and run for 2-300 miles and then run your normal oil, valvoline vr 1 is the answer
 

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Discussion Starter #3
How radical is the cam?
Back then the steel was good, the key will be to insure it fires right now when you turn the key, prelude with a 1/2 inch drill and insure you see oil at every rocker arm, then stab the distributor in at 10 degrees advanced, fill the fuel bowls, give it 4 pumps and hope it starts.

Keep it between 2,000 and 2,500 for closer to 30 minutes varying the rpm by 200 up and down every few minutes, shut it off and change the oil, fill with the same oil and run for 2-300 miles and then run your normal oil, valvoline vr 1 is the answer
Frankly I don't remember which cam but it should be a street cam with a good lope.
Did I already screw up checking that the starter works by turning it over a few times? Why is the key that it fires right away?
I have gas to the carb. If I can't keep it running straight for 20/30 minutes straight am I screwed?
How do I know it's 10 degrees advanced with out running it with a timing light?
Thanks, Jim
 

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If I were doing this, I would drain the oil pan of 15W50 and mix in equal amounts of 10W30 as 50 is heavy and thick.
Now you have two oil changes. I also would add a bottle of GM EOS.
The engine needs good lube and a thinner oil will do a better job.
It is the splashing from the crankshaft lubing the cam/lifters.
Think of it as running your arm through water, now exchange the water for gear lube - harder to move arm.

If you have a point distributor, turn engine over by hand until Cyl #1 is coming up on 10° BTDC,
With ohmmeter or beeper, across point set, or distributor pigtail and ground - should be reading 0 ohms or beeping, turn dist CCW until ohms value change to open or beeping stops.
Snug dist down.
Install vacuum gauge onto full vacuum port.
Once engine starts and is running, adjust timing and mixture for best/highest vacuum reading.
Follow others instructions given.
But, I must say, I am not a professional engine rebuilder - your results may differ.
 

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After 20 years with the occasional rotation of the engine along the way I'd be concerned that any assembly lube used on the camshaft is no longer how you need it to be.

You could pull the camshaft and reinstall or maybe just remove the intake, the rockers and lifters and re-lube the cam through the lifter bores. It all depends on how safe you want to be, you might be taking a bit of a chance if you just fire it up as though it was just recently assembled.
 

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Fill the carb fuel bowls so you don't grind and grind to start. Insure a quick fire up and idle about 1500 rpm. Watch oil pressure and bring to temps. Keep using the light oil until all is good and even then, 50w may still be too heavy unless you have lots of bearing clearances.
 

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In my opinion all of the issues have been covered. Let me restate the issues.

What you are trying to prevent is a lifter/cam lobe failure. The concern others have addressed is the constant cranking causes the assembly lube to be scraped off. My concern is that after twenty years your assembly lube has become jelly, or a semi rigid plastic by now. It's ability to lubricate is long gone.

So now you have no assembly lube. The lifters are now relying upon splash lubrication which doesn't happen at idle. You want to rev the engine to slosh oil up upon the cam. You don't want to maintain any fixed RPM as that will prevent your lifters from wearing in properly (wear on one side instead of rotating as they should). Morgan asked about your cam, as the more radical the cam, the stiffer the springs have to be to keep the lifter on the lobe. Luckily for you it is a hydraulic cam, so the maximum open pressure is not nearly as high as encountered with a really high reving solid cam. If you have a set of old worn out stock springs the chance of a cam lobe wiping would be reduced by replacing the springs with your worn out ones.

I used to remove the outer springs and run my cams only using the inners which reduced the pressure on the lobe and bottom of the lifter. You need to keep reving it up and letting it fall back to a slower RPM to get oil splashed on the cam and reduce speed top keep from wiping it all off quickly.

After a half hour to forty or so minutes the lobes are worn in enough to shut it down and drain out most of the iron filings that you produced by rubbing the metal together to allow the softer lobe to wear into the harder lifter. If you think that first oil change gets rid of all of the metal, replace your stock drain plug with a magnetic one. Next oil change you might be amazed to see all of the metal it attracted.

By the way I built motors in the old days before ZDDP went away, and I still occasionally wiped cam lobes. GM EOS added to the oil is a good insurance policy.

If you can afford it now would be the time to upgrade to a roller lifter engine; before you fill it with cam lobe filings. Roller camed motors need no break in period as the rings seat within minutes if you honed the cylinders with a head plate, and there is no break in for the lifters.

Big Dave
 

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Agree 100% with Dave. Would go one step further given the history of the engine.
Pull the valve covers and intake. Remove the lifters one at a time and first make sure none has already started a bad wear pattern. If so, may as well upgrade to a roller now. The for sure won't get better on their own.

Assuming the lifters all look good and are still slightly convex, clean each one, and lube generously with a good camshaft break in lube. Don't use white grease. Use a product designed for initial install of new cam and lifters.

If you are running the factory stock springs, you are ready to go. If you have aftermarket springs, I would check at least one valve spring for seat pressure. Stock is about 105 on the seat. If it is much higher than that, you may need to break it in with just the inners (some guys do just the outers) to protect the camshaft. Pain in the butt, but so is replacing the cam.
 

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Discussion Starter #10 (Edited)
If you can afford it now would be the time to upgrade to a roller lifter engine; before you fill it with cam lobe filings. Roller camed motors need no break in period as the rings seat within minutes if you honed the cylinders with a head plate, and there is no break in for the lifters.

Big Dave
Well I think I'll contain my excitement for getting the motor going and take your advice and upgrade to a roller before doing any damage to what I have.
So I guess the next question is which cam kit to choose.


Here's what I have:
427 4-bolt main .030 over 1975-87 truck block (454 block) roughly 10:1 compression
Closed Chamber oval port heads 2.06 intake/1.72 exhaust / Minor bowl work
Edlebrock RPM Air Gap
Aluminum Holley 850 double pumper
Muncie M-20 Wide Ratio 1963-65 / 2.56 1st - 1.91 2nd - 1.48 3rd - 1.00 4th - 3.16 reverse
12 bolt with 3.90 Richmond gears


Any suggestions?
Thanks, Jim
 

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Discussion Starter #13
I want to thank everybody for their input and for making me come to my senses. I spoke with the friend that built it so many years ago and he agrees. We'll work together on this and because of which I'll get to learn along with getting it right. What's even more special is I'm able to reacquaint myself with a friend I've lost touch with over the years whose a great car guy. So thank you! This is a great website/resource for us guys who aren't too knowledgeable but still love Camaros. I've gained a lot of knowledge over the last couple of years and am excited to continue to learn with your help.
Thank you again, Jim
 
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