How did the factory break in cams?

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MrJLR

MrJLR

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Did they actually run them in for 30 minutes, varying the RPMs, then change the oil and filter again?
And if so, was the engine in the car or on a stand?

Seems so costly and laborious. ....?!

Anyone know someone who worked the line back then?

Thanks

Jeff
 
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That is a good question, my best guess is they did not, oil was not a concern back then and the spring rates on stock factory built engine are not as high as some of todays performance cams.
 
d1970 said:
X2. Check the operators manual for any car and it has a section about break-in recommendations for motors
Click to expand...

Yes.....but no elaborate cam break in like today.....
I'm specifically curious about the cam break in.
 
in was through the Oshawa plant back in the 60's.Every car was test run on rollers
as part of the production process...at least that's what they showed us.
..on a side note i don't think you vary rpm during cam break in..steady 2500 rpm 15 min.
 
Dont know about the factory, but you should......
Here is my recipe: I try to run it approx. 20 minutes between 1600 - 2800 rpm's, and I usually do this by ear because I'm under the hood.
Here are a few tips:
1. Have someone there to help watch & help. They will help look for leaks, radiator level, heat gage, and hand you something if needed, etc. I had my teenage son help on the last one, but your wife can help just as much. Just give her her a few heads up....
2. It isn't a bad idea to have a garden hose handy incase the temp begins to get uncomfortable, you can put a nice mist on the radiator.
3. leave the distributer somewhat loose so you can "smooth it out" by turning it a little so it doesn't have to be shut off.
4. Use a carb that you know is in good working order.

Should your car shut off or you need to shut it off, get it going again and continue the break in procedure. I'm sure I've left some things out..... Remember, I'm a hobbiest, not a professional shop. I've done this a few times through out my years, but not daily or weekly like a machine shop. I've never lost a lobe, though...
 
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ir3333 said:
in was through the Oshawa plant back in the 60's.Every car was test run on rollers
as part of the production process...at least that's what they showed us.
..on a side note i don't think you vary rpm during cam break in..steady 2500 rpm 15 min.
Click to expand...
Comp Cams recommends 2000 rpm with occasional blurps to 2500 rpm for 30 min. with the one I just broke in.
 
ir3333 said:
in was through the Oshawa plant back in the 60's.Every car was test run on rollers
as part of the production process...at least that's what they showed us.
..on a side note i don't think you vary rpm during cam break in..steady 2500 rpm 15 min.
Click to expand...

Yes that is correct. GM and probably the other car makers ran the new cars on rollers to test the transmission, brakes, check for leaks and other things before shipping the cars to dealers, but it was only for a few minutes. They still do it today, but the testing equipment is more sophisticated today. That's why there is the a section on motor break-in, in the operators manual.
 
They busted the motor off and pulled the cars out into the storage yard and cut them off.
 
Not sure on the mopars but GM had some pretty stout factory cams in the L78 396 and the L88 427 ,I would think those would have been broken in before hand.
 
RustyRatRod said:
They busted the motor off and pulled the cars out into the storage yard and cut them off.
Click to expand...
That is what they did. Got to the end of the line, started them, drove out the building to storage area, shut them off. did not turn on again till they were loaded for shipping. I saw this first hand at GM plant in Flint. My father was a Hocho for GM before he passed.
 
... lots of zinc in the oil and lead in the gas back then.
no one was cutting corners on metallurgy / quality steel and alloys.
 
Back in the old days, I heard that they used to hot test every engine at the end of the line for 10-15 minutes. I know this because some of the old timers used to tell me about how they would put too much advance on the 440 six packs when installing the distributors and they would shoot flames to the roof when they backfired.... (sometimes the workers did it on purpose for the entertainment value...)

But I don't think that they ever ran them more than 10-15 minutes at the factory...
 
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Plenty of zinc in the oils and much lower spring pressures made all the break-in that we now do not needed in standard production cars. Heck, when I started gearheading in the 70's we did not go through all this break-in bother AT ALL for run-of-the-mill performance cams even with heavy duty valve springs. Maybe the top level engines were doing it, but not everyday hot rodders; the break-in focus was more on rings.

If you have a good zinc oil, and standard cam, I'd not bother with it even today for a standard stock cam and springs. All of this has to do with the rash of cam failures in the middle of the last decade, when ZDDP levels in oil were dropped by mandate from the EPA, along with higher and higher lifts and spring rates being used more and more commonly. This is why, if the spring seat pressures are under 300#, I decided to not bother removing inner springs for cam break-in; it is below a critical level of lifter-to-lobe pressure IMHO. The cam manufacturers will tell you to do it, but much of that is for their protection, IMHO.
 
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a lot of truth in above post ^^^^^. Spring pressure and zinc play a big part in it. I still follow a break in procedure because its not hard to do...
 
How did the factory break in cams?

They handed the car to the customer and told them via owners manual not to sit and let it idle, and don't beat the hell out of it.
 
i know dealers would tell clients to break in their new car by driving it like you will be driving it all the time.And i know young guys who bought new cars back in the day and wound them up
and drove them hard from the very first day.
 
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