Cam break in?

hasa68mustang

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my dad mentioned something about having to "break" the cam in? I have everything installed and was doing a compressiong test before starting when my mom called and said we had to come home to eat dinner... I cant wait to hear the new "lopey idle" I havent heard my car run in a few months... I just want to start it and drive it home... I will have my camera and video camera on hand when I leave in a few minutes so a quick reply would be helpfull, Thanks, Tommy
 
OK, You should set the shortblock with #1 at TDC on the firing stroke.

Ensure the lifters are all greased with assembly lube, as is the cam. :!: Remember that cranking the motor before it starts up, is wiping a lot of this off, risking damage to the new cam. :shock:

Verify your ignition before installing. Do this by hooking up the dizzy and coil etc, but not installing the dizzy. Clip a ground lead from the distributor case to the block or body. Power up. Now spin the dizzy with your hand twisting the drive gear, and see that you get a good healthy spark out the coil lead.

Now install the distributor with the rotor button lined up with #1 terminal. This corresponds to the piston position set before, so you are sure it will fire easily.

The head can go on. After allowing the correct relax time between torque settings, install and adjust the rockers. Use assembly lube to both ends of the pushrod, and on the rocker arm wear surfaces. The correct setting for a lifter in this case, is with no pressure, give it a few minutes to fully extend. Grasping the pushrod between your thumb and first finger, you should feel a little slack as you try to jiggle it up and down. The assembly lube will make this feeling a bit claggy.

Tighten the adjuster until you can no longer feel any up-down motion possible. Now add one full turn. Do this separately for each of the inlet and exhaust on #1.

Now, if your valve stem tips are within say 60 thou of each other in height, you can cheat. Measure the amount your rocker ajuster protrudes from the arm after setting, and copy this measurement to all the other cylinders.

That's the presets; don't overtighten the rocker cover and use a sealant like Permatex to hold the gasket in.

Now, you need to be sure the carb works. Use a carb from a motor you heard running within the last few days. Once they dry out and sit, problems increase in potential. Fill it through the bowl vent, and verify by tweaking the throttle shaft. As only the head was off, not the whole motor apart, there's no real need to prime the oil supply.

Check your electricals again, connect the radiator up and fill with coolant. Check your oil for contamination, and level. Use non-synthetic oil for the break-in period. The motor should now fire up without any hesitation.

Run it at 200RPM without any speed variation, for a good 20 minutes. Monitor the time elapsed. If you have to stop it, next restart should be at the same speed, for the remaining time.

After that, check your lifter adjustment and oil, and it should be able to run a few miles before dropping the oil and filter.

See! Simple. :wink:
 
thanks, Thats exactly what my dad said but I wanted to make sure he said run at 2k for 20 minutes.. is there a cheaper way of doing this.. I mean gas prices and all... :lol:

*edit* I had a feeling addo would see this and post a huge thing about it... ok well the motor was already completely assembled the way you described so Im o.k. there but one thing.. I dont think my car will idle at 200 rpms... lol my dad does have a 41 chrysler that runs smooth enough to run something terribly slow.. slow enough were you can count the fan spinning... ok well I am off to start the beast! I have my camcorder and camera with me so I can show off my freshly painted engine/compartment/accesories! Tommy
 
Tommy, welcome to the cam club.
Do as Adam said, but I also add EOS, this is an additive sold by GM dealers specifically for camshaft brakin. Its called engine oil suppliment.

Just add it to the crankcase or better yet after the moly lube is put on the camshaft & lifter submerge the lifter contact area in EOS & pour the rest on the camshaft.

Using Adams post & the additve EOS I have never had a camshaft problem. William
 
It is easy to get excited and distracted when starting a new motor. :shock: When it fires, first look at the oil pressure. This sounds like a no brainer but it is the most expensive screw up and happens more often than you think.
 
Tommy, before engine lite off you should have prelubed the engine by using a power source to spin the oil pump before the distributor was installed so you have full oil pressure before starting.
As Stubby mentioned it is a very good practice to make sure you have oil pressure before lighting the fire.

With the light spring pressures used on our engines I don't think you will have a problem.

If you were starting with an engine with 400# of spring pressure you better have your act together, but with 90-110# of spring pressure you shouldn't have a problem. William
 
hey you guys described me.. extremely excited.. well she started right up, and I put the pedal down a little bit and noticed I didnt have my tach hooked up (turned out I didnt have the ground wire attached so we turned it off) It was also 10 pm so I couldnt peacfully go out and keep the rpms above 2000 rpms (Its in the middle of a neighborhood and with my glasspacks) before I turned it off I had to let off and it idled for a mere second.. and I couldnt stop grinning... if only you guys knew how much I just want to open the door and drive her... I am stuck driving an ugly gas hogging truck but it makes up some with its flowmaster exhaust and 360ci engine... I remember the good ol days, windows down, radio cranked up, wind in my hair... I say 25 days before someone runs into me... and I have a feeling it will be in aparkign lot and theyll leave...
 
You can even use a Fluke style meter as a tach, if it has frequency. Hook it across the coil terminals, and divide by three. That means, you're looking to read 100Hz.

(Why? It fires six times per two revolutions; that's three times per rev. 2000RPM is 33 1/3 revs/second.)
Sounds like you still need the full 20 minutes @ 2KRPM. Sorry about leaving off the zero.
Run it at 200RPM
Thought I was going to pay for half another cam. :oops:
 
lol your joking right??? :shock: No I knew what you meant, I read the article Alex said to read along with some others ans what you guys suggested so I think I was pretty well prepared, so now hopefully today I will push the car outside start it and run it for the 20 minutes... Ill get a video of how it sounds, I dont know if anyone is like me but I still want to hear what a "lopey idle" sounds like, Im used to hearing my steady drone of an exhaust note.... then I goto the mopar nationals and the cars have some outrageous cams... and I know mine wont sound like that but I was unsure on how much of a lobe I could expect... If it sounds like what it did when it idled before I shut down I will be impressed.... well the car is starting to come together.. I took some clips of the engine compartment as well as some other things... right now I have the body assembled for the last couple coats and clear, and we got a piece for our hvlp gun that we needed so were spraying good! hmmm I also put in the heater core, and I ran out of paint unfortunately so I am stuck trying to find retarded things to do... ummm I think thats about it... Tommy
 
Howdy Matt and All:

Awww, the thrill of a new engine start up!!!

You've got good advice here. And it sounds like your Dad has been around the block a time or two too.

One thing that we recommend is to do initial startup with the valve cover off so that we can observe the oil pressure coming up and coursing through the rocker shaft and out each rocker. A plugged shaft or rocker hole can quickly ruin a rocker, the shaft, or a pushrod tip.

You will also note that the upper oil drains down each pushrod and onto the lifter and then the cam. That supply and system give our engines an advantage over any V8 or slant type engine when it comes to getting oil to the cam shaft lobes.

Also make sure that your carb does not have too high float or too rich choke on start up. Too much gas can dilute the oil. Not good!

Gas is too expensive to waste.

After initial start up and check, plan to drive the car softly for the 1st 300 - 500 miles. It is best to avoid short trips, stop and go traffic and high speed blasts down the freeway. Change the oil and filter after this period. It is fun to tear apart the filter cartridge and inspect the innerds for junk. A new filiter and fresh oil is cheap insurance.

I think you're going to have a very good day.

Adios, David
 
CZLN6":214988fq said:
After initial start up and check, plan to drive the car softly for the 1st 300 - 500 miles. It is best to avoid short trips, stop and go traffic and high speed blasts down the freeway.

Your joking right???...hopfully... (kidding) the only way I can drive my car is in town so I really dont have much of a choice... 300-500 miles eh? thats a few weeks of having to drive my car softly... I remembered right before I parked my car she was tuned well Iand taking off I could really get going, stock it wasnt hapenning... also when I just bolted on the holley... both ways to drive normally it was to the floor, and ol... er elderly ladies would pass me and smile.... :oops: well I still never got to run the car, but I will take the cover off to check about the pressure, I have to goto work then a friends birthday party where its always fun.. we stay up all night and if you dont you get drawn all over by yours truly :D ok well I am off for work... and I will post some pics of the freshened compartment... I scrubbed and cleaned and painted everything so shes looking pretty good... this has got to be one of the most random posts in the forums history...
 
Ok well heres the story... 99% good stuff to say... ok Well I got everything ready and started the car I set the idle up to 1900 and gave it gas to bring it up whiel listening to the radio... after the 20 minutes I set the idle back down to something like 800 rpms... its sounds like a race car... the idle is mpressive although it isnt practical for driving... it only took me 5 starts to get her outta the garage and another 1 to turn around.. I have to set the idle up a bit.. I got a video of my stalling and starting.. I bet you would all love to see that.. Ill get another in a week after the cam is fully broken in and I can do a burnout "safely" I also painted 75% of the car I had to go home because of the time, tomarrow I will finish painting and possibly clear then I can get the chrome on and drive her to school friday!!! :D I cant wait... oh and the 1% wrong was the fact that it idles liek a race car and stalls all the time.. I got the hang of it after I got it turned around and drove it back up and in without stalling.... I am sure the car will turn heads... it revs alot faster and seems better but I haved really driven it.. ok time for bed for energy tomarrow...
 
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