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Author Topic: Rebuilt engine....picking an oil and breaking it in  (Read 15153 times)

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Offline BenM

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #15 on: April 18, 2011, 10:32:03 PM »
I use diesel oil in everything (especially the diesel). Usually Rotella. The 5-40 synthetic is good year round, and you can get it at nearly any truck stop if you need a quart. That's great for a part-time car where you may not get 7,000 on it every six months.

The diesel oil still has more ZDDP (zinc) and other wear additives then regular oils, plus high detergents required to keep diesel soot in suspension. It really cleans out your sludge well.
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1987 AMC Eagle Sedan -- 1976 Pacer Coupe -- 1968 Pontiac Tempest Custom S -- 1940 Mercury (& a 2002 Jetta Turbodiesel, 5 spd., the Wife's Daily Driver)

Offline priya

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #16 on: April 18, 2011, 10:39:22 PM »
High Zinc oil is a MUST HAVE for breaking in a flat tappet cam.
No questions asked.
I've seen people ignore it and wipe a cam in less than 500KM.

Most diesel oils don't have much zinc in them anymore aswell as Casper stated.

I've seen plenty of flat tappet high performance motors eat cams using regular oil.
When you've got a 5,000-10,000$ motor whats a bit of extra money for an additive or decent high zinc oil?

When I ordered my cam from Comp Cams, they specifically said the camshaft WOULD fail without high zinc oil or an additive... Every motor I've built that's flat tappet, Ive used additive or high zinc oil.

Such stories remind me of other stories of conventional wisdom are often wrong, like how gas pumps often have a picture of a cell phone with a red line through it when there is no possibility of a cell phone giving off a spark and causing a fire.  Or, the old standby that sugar in the gas tank will melt in the cylinders and seize up an engine.  After many years of believing that one and hearing many stories of someone who had a motor ruined by sugar in the tank or someone who knew someone who experienced that one day it occurred I thought "I bet sugar won't even dissolve in gasoline" - it won't.  A short time later I saw a test on TV (mythbusters?) where they put it to the test and sugar in the tank had no effect on the motor.   A few months ago someone brought a car into my husbands shop because someone had put sugar in the gas tank.  He dutifully drained it as the customer requested and then when the other mechanics didn't believe him that it was unncessary he poured the sugared gas into the tank in his truck making sure to included the undissolved sugar grains that were at the bottom.  We still laugh about that one.  Still people will absolutely insist that sugar in the gas tank will ruin a motor because it happened to them, or someone they know.

We won't be using Zinc additives to break in my motor.  As far as new diesel oils containing more zinc, new diesels have catalytic converters so if the zinc was removed for the sake of catalytic converters this does not seem likely.
« Last Edit: April 18, 2011, 10:43:32 PM by priya »

68AMXGOPAC

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #17 on: April 18, 2011, 11:24:55 PM »
So the conclusive answer is Obscurity , if your not confused by all this yet, you will be after a few more posts !!

ok, here's my 2cents. I rebuilt a 1952 4cyl . 403cu.in last year.I used assembly prelube on everything when assembling( this is a must) ,and plastigauged all the tolerences, then ran straight 30w for a break in oil to seat the rings.It has flat top Ross raceing pistons and Total Seal - gapless rings.I ran it through break-in, then switched to a 5w-30.With the piston wieght reduction and balance , I can run about another 15-20% above normal max rpm, no issues.

So now that your still wondering what to do , at least I got to tell you my story : )

All kidding aside, compile all the info you have just got from everyone and make a decision.Better to be safe than sorry.

Offline eaglefreek

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #18 on: April 18, 2011, 11:45:24 PM »
We won't be using Zinc additives to break in my motor.  As far as new diesel oils containing more zinc, new diesels have catalytic converters so if the zinc was removed for the sake of catalytic converters this does not seem likely.
You can do whatever you want, it's your car. You may be fine, but is the gamble worth it to save $10 for a bottle of additive?  Zinc was not removed just reduced. Do an internet search for flat tappet cam failures and you will have plenty of reading to do.
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Offline Sunny

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #19 on: April 18, 2011, 11:52:30 PM »
Such stories remind me of other stories of conventional wisdom are often wrong, like how gas pumps often have a picture of a cell phone with a red line through it when there is no possibility of a cell phone giving off a spark and causing a fire.  Or, the old standby that sugar in the gas tank will melt in the cylinders and seize up an engine.  After many years of believing that one and hearing many stories of someone who had a motor ruined by sugar in the tank or someone who knew someone who experienced that one day it occurred I thought "I bet sugar won't even dissolve in gasoline" - it won't.  A short time later I saw a test on TV (mythbusters?) where they put it to the test and sugar in the tank had no effect on the motor.   A few months ago someone brought a car into my husbands shop because someone had put sugar in the gas tank.  He dutifully drained it as the customer requested and then when the other mechanics didn't believe him that it was unncessary he poured the sugared gas into the tank in his truck making sure to included the undissolved sugar grains that were at the bottom.  We still laugh about that one.  Still people will absolutely insist that sugar in the gas tank will ruin a motor because it happened to them, or someone they know.

We won't be using Zinc additives to break in my motor.  As far as new diesel oils containing more zinc, new diesels have catalytic converters so if the zinc was removed for the sake of catalytic converters this does not seem likely.


Mythbusters is a great show. They actually also tested the cellphone at a gas station myth.

I don't see what the harm is, for an extra few bucks to gaurentee it.
I spent my childhood at a track, as my father built racecars up until about 10 years ago.. [15 years ago he stopped fulltime, then did it only part time.]
I have first hand watched cams be wiped on non stock motors because conventional oil does not provide a proper break in.

Call any major cam company, and ask them and most state the cam WILL be damaged if it is not properly broken in with high zinc. [Infact a lot of camshafts I've ordered lately have come with a free zinc additive for the break in.]

Shell Rotella was the last oil I knew that had zinc, but I'd assume it's gone now.

Also, I have to agree with Eaglefreek.. what uses a flat tappet these days?

My vote is for the extra few bucks, what can it hurt.
Proper break in is important andI've NEVER seen a performance shop break in a new flat tappet motor with just regular 5w30 off the shelf.

Offline BenM

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #20 on: April 19, 2011, 12:00:13 AM »
I get all my oil info from the bobistheoilguy forums. If you have any questions on additives, who has them, doesn't and how much there is in something, go over there and lurk around. Those guys are serious about oil, they have the lab tests to prove it.
NSS#47184

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Offline Sunny

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #21 on: April 19, 2011, 12:17:29 AM »
I get all my oil info from the bobistheoilguy forums. If you have any questions on additives, who has them, doesn't and how much there is in something, go over there and lurk around. Those guys are serious about oil, they have the lab tests to prove it.

GREAT website. Pretty good unbiased information.
The articles from the site hosts themselves are great, the forums are full of arguing though hah.

Here's what I'm going by:
-Every Flat Tappet Cam I've installed says in nice big bright letters DO NOT BREAK IN WITH CONVENTIONAL OIL.
-I've seen cams wiped out in less than 500KM due to improper break in
-It's 7$ to protect a motor

I don't listen to someone just because they're a mechanic. Having worked in a few [and still currently working in] a shop, it's very clear mechanics don't know everything. Plenty of mechanic's cant peice together a properly matched high performance motor. They can just replace XX part on XXX car. I quit my apprenticeship because these days it's just "hook scan tool up.. read codes.. replace part." So I went to persue a different career track, and keep it as a hobby. I learned a lot though, growing up with a father, and both grandfathers being mechanics.. hah.


That's not a shot at Priya's husband, to clarify.

Offline Sunny

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #22 on: April 19, 2011, 12:34:27 AM »
Z-max is mineral oil.. DO NOT USE IT.
Lab test's have proven it, and the FTC had a lawsuit pending because it was causing more harm then good.
Carrol Shelby got a pretty decent sum of money to promote it.

I'll send you a PM with a few different good zinc additives you can use for break in or constant use.

68AMXGOPAC

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #23 on: April 19, 2011, 07:17:31 AM »
Shell Rotella is still around. I just picked some up at Tractor Supply,I needed it for a 58 Porsche I am working on.

Offline Sunny

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #24 on: April 19, 2011, 10:57:49 AM »
Shell Rotella is still around. I just picked some up at Tractor Supply,I needed it for a 58 Porsche I am working on.

Not sure of the Zinc and Phosphorous content anymore, but I know it was one of the last off the shelf oils to have high ammounts. Guy's here were buying it in truckloads hah. A few engine builders around here still stock it in bulk.

Offline BenM

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #25 on: April 19, 2011, 01:38:28 PM »
Here's what I'm going by:
-Every Flat Tappet Cam I've installed says in nice big bright letters DO NOT BREAK IN WITH CONVENTIONAL OIL.
-I've seen cams wiped out in less than 500KM due to improper break in
-It's 7$ to protect a motor

Yes, always follow directions.  ;) If you're not sure of what to do, all the cam manufacturers have service lines, and they definitely want you to be happy and be a repeat customer. If they're recommending a grade, style, or even brand for breakin, it's worth the cost for long term life of your engine. Talk to those guys and get a recommendation.

The last time I looked at the numbers, even the modern low-emissions diesel oils have higher zinc and phosphorus levels then normal oils. If you can find CH-4 or CI-4, those should be the older high-zinc formulas. CJ-4 is the lower catalyst friendly blend, but CJ-4 still specs more zinc then the newer gasoline oils. However, I haven't looked at oil in at least a year, so I may be out of date.
NSS#47184

1987 AMC Eagle Sedan -- 1976 Pacer Coupe -- 1968 Pontiac Tempest Custom S -- 1940 Mercury (& a 2002 Jetta Turbodiesel, 5 spd., the Wife's Daily Driver)

Offline Obscurity

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #26 on: April 21, 2011, 05:47:04 PM »
Well, I've come to the conclusion that I'm definitely using the Zinc additive, and a relatively generic oil (one the guy at NAPA said he knows other people have broken engines in with).
I'm sure that the guys at the shop used the proper lube when assembling the engine, they were VERY good respecting the fact that I cared about this engine, and the amount of money I put into it. They mentioned that they had thrown in a couple hours for free because they realized how costly it had been. True or no, it wouldn't surprise me, they did a LOT of research at very least, most likely for free, they were.
The landlord/tranny mechanic....I got my oil, additives, spark plugs and oil filter. A couple more parts yet to come in and it'll be good to go....I'm going to talk to him, perhaps print out this thread and take it to him. I want to insist that he primes the motor, and that I am THERE when it starts for the first time, and I will thoroughly explain the break-in to him. Here's hoping though that it starts the first try!!! It could turn out to be quite the ordeal.
He pulled the car out, since we were waiting for parts and he had other work to do (fix his plow so we could use the driveway!). I honestly think he expects to just throw the absolute minimum parts on to get it running and then pull it into his shop to finish the work. He isn't going to be pleased when I correct this idea of his, but hey, he is getting "paid" for this. (he is actually getting my Grand Am in return for it....I could sell it for about $2500 if I wanted to take the time)
Thanks for the info everybody, I'll probably read this thread a dozen more times before break-in day! :)
"In order to attain the impossible, one must attempt the absurd" -Miguel de Cervantes

wagoneerhauler

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #27 on: April 21, 2011, 06:30:36 PM »
Another thought.  Fresh gas for the tank since this has been sitting awhile.  Get a few 5 gal cans and add it, depending on how full it is now of course.  (or maybe I should have used liters  ;)  )

Offline BenM

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #28 on: April 21, 2011, 07:49:14 PM »
No, you don't want to put a few gallons of liters in the tank. I've heard that stuff is thicker then diesel. Better stick to gas. ;)
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wagoneerhauler

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Re: Rebuilt engine....picking an oil and breaking it in
« Reply #29 on: April 21, 2011, 08:00:31 PM »
 ;D

 

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