New Engine Break in Anxiety Woes

[DT1]

I just received my Chevy Performance 350 and I'm installing it this weekend. I've broke in quite a few engines in the past but I still can't get over the anxiety of running a new engine at 2000 rpm for 30 minutes straight. You know...The smell of new paint frying, checking around for water/oil leaks and listening for any sound that doesn't seem normal.

In the past I would run the engine at 2K RPM for 10 minutes, shut it down to cool and repeat two more times. I've never had a problem doing it this way but I've always wondered if I was just lucky.

I'd like some input about this procedure. Is it an acceptable way to go or am I risking catastrophic cam damage?

[geezer#99]

I’ve always gone 20 minutes straight time. Varied the rpm between 2000 to 2500 rpm.
That 20 minutes is like an eternity!

[mattfranklin]

I'm the most worried about what my neighbors think when I first fire mine up. Vintage spec. motor with mechanical cam and loud pipes. I've heard 20 min at 2000 is what I'll need. Maybe I'll do mine mid-day when most folks are at work.

[weq92f]

I would go the full 20/30 minutes first run rather than trying to spread it out with multiple shorter runs.

Remember, it's about bringing the components up to full operating temp as much as it is about mating/bedding the surfaces together. 10 minutes really isn't enough time to get there IMHO.

Hth,

-klb

[Captainfab]

With the oil these days engine breaking with a flat tappet cam is critical to your camshaft living. I would follow the breakin procedure recommended by GM as well as using the recommended breakin oil. Plus recommended oil change intervals thereafter.

[YoungPup1977]

The reason I believe for the concern on oils of today is that most of the engines of today are roller type camshafts....breaking in a Hyd flat tappet camshaft is critical regarding the type of oil you use...look for zinc based oils to break your engine in....if in fact you do not have a roller type of camshaft....

the duration of "break in" can be debated by others but I recommend what the engine builder (GM) calls for....thanks.

[BigRandy]

If you want to read up on oil and flat tappet motors this is a long but informative blog from a guy who claims to have done extensive, scientific research on the subject. He
doesn't believe that oils with more zinc and phosphorous are the end-all be-all to protection. They are important, but only part of a more complex "recipe" of additives.

https://540ratblog.wordpress.com/201...-test-ranking/

IOW, you shouldn't just pick a high zinc oil and call it good. I like facts backed up with science, but I don't know the guy or see the testing so I can't say he's right or wrong - just posting the link. The only oil fact that I know of is that everyone has a different opinion based on reports, neighbors, brother-in-laws, some guy at work, or real experience in a shop.

It's normal to want what's best for a new engine and I'd be in the same boat as the OP on this one if it were mine. It's hard to argue with experience so for the break-in I'd probably ignore any marketing hype and listen to people who build motors for a living .

OP - let us hear her run when you get it fired up.

[YoungPup1977]

Not to debate this zinc oil stuff, I would simply follow the instructions provided by the company (GM) who the OP bought the engine from.... they would be the ones who will ask the questions after the break in takes place and if issues arise. GOOD LUCK !!!!

[panhead59]

Use oil specifically designed for break in. Won t hurt to run it a couple hundred miles. Then change with high zinc oil. Just make sure it is ready to start before cranking. You don't want a ton of revolutions before she fires and the oil gets circulated. Prime with drill first !

[nikwho]

I only shut down prior to full break in time if I have a significant issue that I need to immediately resolve. That's only happened to me once. Make sure that you KNOW that you're on TDC, not 180° off. You'll need to pull the distributor to run the oil pump. The reason for the varying between 2000-2500 RPM is to get some splash oiling from the crank. I've read that allegedly the crank will splash oil in different places on the camshaft between those RPM's. I've always taken a carb that's known to run well and turn the idle mixture screw up a bit. I try to quickly get the engine speed turned up with the idle speed screw so that I don't have to hold it by hand. I like to have a tach, an oil pressure gauge and a temp gauge hooked up for break in. After everything is checked and working well, I'll adjust the timing when I get bored. It's not a huge priority to me, but I've always had time sitting and staring at the engine run, so I take a couple of minutes to set the timing. It's fairly normal to see higher than normal engine temp during break in. I've read that this is due to tight bearing clearances. Use the oil and procedure and any additives that the engine manufacturer reccomends. Like stated above, you'll have to answer to them about break in procedures if there are problems. You will not want to tell them that you did something that contradicts their procedure. As for oil to run after break in, I like to run Valvoline VR-1 Racing Oil. It's got the ZDDP/zinc in it already.

Good luck!

[YoungPup1977]

Did the engine come with instructions of "HOW" to break the engine in ?

Its cool to ask experts on a forum, but if you do not follow the engine makers procedure for their "break in procedure" it might void the warranty, just wondering exactly what GM (or whoever you got the engine from) recommends.. Thanks.