New engine break-in - The 1947 - Present Chevrolet & GMC Truck Message Board Network

6TNiner · 09-04-2009, 05:01 PM

What is the proper way to break-in new engine? I've got a new GM Performance 350 crate dropped in on my 69. Mechanic said to run it hard? Any suggestions. Have under 20miles on run gently. thanks all.

Todd327 · 09-04-2009, 05:27 PM

I have always heard that you need to do a mix of driving. A little around town, a little at high speeds. You were supposed to avoid putting on the highway and running it at a constant speed for a long time. I seem to remember that most mfg. recommended a short oil change after 600 miles or so.

LOW DOUGH · 09-04-2009, 05:33 PM

I have been told to run Non-Detergent straight 30 oil for the first 500 miles or so. To seat the rings. That's what I did. I think that my motor I got came with a tag that said to do this.

You might get more feedback in the engine section.

cparman · 09-04-2009, 06:37 PM

my .02 is to run it like TODD described. When I put my 330 hp crate motor in my Blazer, I will run it for 15-30 minutes, and change the oil. Then run it 100-200 miles and change it again. 500 miles and do the same. all the while running at differing speeds. never running at a steady rate, like 40 mph or so. after i get to 1000 I will change it again, and when it gets to 4000 i will use a true synthetic like AMSOIL

mclairmo · 09-04-2009, 06:55 PM

I would also use a zinc additive like ZDDPlus so you don't wipe out a cam lobe, assuming you do not have roller lifters.

**special-K** · 09-04-2009, 09:58 PM

What`s a good break-in oil to use?

rico7769 · 09-04-2009, 10:01 PM

switch up your driving patterns. NOTHING consistent and definitely not freeway driving. Change the oil for sure. The crate probably recommends it like the other post said if you read the warranty info that shipped with it. The oil is break in and not what you would want to keep in it after around 20-30 miles or so. I would change again at around 200 too. All good advice in the previous posts. Good luck and congrats on the new motor!

jamesi20 · 09-04-2009, 10:12 PM

Quote:

Originally Posted by special-K

What`s a good break-in oil to use?

used to be shell rotella t but I think it has changed in the last few years.

texanidiot25 · 09-04-2009, 10:13 PM

What's wrong with freeway driving, I never quite understood the "no constant RPM"

BCOWANWHEELS · 09-04-2009, 10:42 PM

Definatly use non-detergent 30. 500 miles max. And drive it like your gonna for as long as your gonna own it. No super hi rpm,s also..... Jmo

P.S
DOCUMENT WITH RECIEPTS AND MILAGE DRIVEN FOR WARRANTY PURPOSES.

unclewatts · 09-04-2009, 11:07 PM

Quote:

Originally Posted by special-K

What`s a good break-in oil to use?

When I was a kid whenever we bought a new car the dealer put in 10 weight non-detergent. I have heard (Cause I don't buy new cars) that now the dealers are just putting in 10-30 detergent. One thing I do know is don't use synthetic to break in a new engine! Wait until about 5000 miles and then switch over. I'm not recommending anything just relaying what I have observed.

**Green Machine** · 09-05-2009, 02:35 AM

Check out this thread - lots of good info -

http://67-72chevytrucks.com/vboard/s...d.php?t=355062

**special-K** · 09-05-2009, 05:20 AM

For decades the recommendation has been break it in easy with no constant rpm/load.For decades motors had no problem making enough cylinder pressure to seat the rings.It`s all about letting everything seat itself.If it`s a manual the clutch needs to seat itself as well.

In that thread someone said they use moly rings because they break-in faster.I was taught the opposite.Cast is softer and you want the rings to seat to the cylinder,not take material off the cylinder.The rings are the wear part.Moly is harder and will last longer and resist cracking better.I would use cast rings on a motor to assure a good break-in on a motor that I overhauled.I`d use moly on a motor I rebuilt and expected a long life from.
I`m no expert,but that`s who I get guidance from.If I`m wrong I`m all ears.

AusMarty · 09-05-2009, 05:36 AM

When I had my big block run in on the engine dyno the guy loaded it right up at full throttle but didn't let it rev above 3000 rpm, he did this three times and a total of 15 minutes in all, then we done two pulls one at 5000rpm and one at 6000rpm to see what hp and torque we got, the idea of loading the engine up and not letting it go above 3000rpm is to increase the pressure in the cylinders which forces the piston rings against their bores and bed them in, so if I were driving while running an engine in I would find some hills and load it up without reving it too hard to avoid glazing

09-04-2009, 05:01 PM	#1
6TNiner Registered User Join Date: Sep 2008 Location: Seattle, WA Posts: 24	New engine break-in What is the proper way to break-in new engine? I've got a new GM Performance 350 crate dropped in on my 69. Mechanic said to run it hard? Any suggestions. Have under 20miles on run gently. thanks all.

09-04-2009, 05:27 PM	#2
Todd327 Registered User Join Date: May 2009 Location: Salisbury, NC Posts: 24	Re: New engine break-in I have always heard that you need to do a mix of driving. A little around town, a little at high speeds. You were supposed to avoid putting on the highway and running it at a constant speed for a long time. I seem to remember that most mfg. recommended a short oil change after 600 miles or so.

09-04-2009, 05:33 PM	#3
LOW DOUGH I'M TRUCK CRAZY! Join Date: Oct 2006 Location: Sachse, TEXAS Posts: 1,737	Re: New engine break-in I have been told to run Non-Detergent straight 30 oil for the first 500 miles or so. To seat the rings. That's what I did. I think that my motor I got came with a tag that said to do this. You might get more feedback in the engine section.

09-04-2009, 06:37 PM	#4
cparman sharp as a marble Join Date: Jan 2007 Location: atlantic beach,florida Posts: 1,082	Re: New engine break-in my .02 is to run it like TODD described. When I put my 330 hp crate motor in my Blazer, I will run it for 15-30 minutes, and change the oil. Then run it 100-200 miles and change it again. 500 miles and do the same. all the while running at differing speeds. never running at a steady rate, like 40 mph or so. after i get to 1000 I will change it again, and when it gets to 4000 i will use a true synthetic like AMSOIL

09-04-2009, 06:55 PM	#5
mclairmo Registered User Join Date: Jan 2006 Location: Take Off Posts: 1,908	Re: New engine break-in I would also use a zinc additive like ZDDPlus so you don't wipe out a cam lobe, assuming you do not have roller lifters.

09-04-2009, 09:58 PM	#6
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,861	Re: New engine break-in What`s a good break-in oil to use? __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

09-04-2009, 10:01 PM	#7
rico7769 Hybrid67 Join Date: Jan 2009 Location: Martinez, GA Posts: 195	Re: New engine break-in switch up your driving patterns. NOTHING consistent and definitely not freeway driving. Change the oil for sure. The crate probably recommends it like the other post said if you read the warranty info that shipped with it. The oil is break in and not what you would want to keep in it after around 20-30 miles or so. I would change again at around 200 too. All good advice in the previous posts. Good luck and congrats on the new motor! __________________ Keep em' Running! All show.....no go

09-04-2009, 10:13 PM	#9
texanidiot25 Eat My Rust Join Date: Jan 2007 Location: Cypress, Texas Posts: 3,362	Re: New engine break-in What's wrong with freeway driving, I never quite understood the "no constant RPM"

09-04-2009, 10:42 PM	#10
BCOWANWHEELS Registered User Join Date: Nov 2006 Location: KINGSPORT,TN. Posts: 3,035	Re: New engine break-in Definatly use non-detergent 30. 500 miles max. And drive it like your gonna for as long as your gonna own it. No super hi rpm,s also..... Jmo P.S DOCUMENT WITH RECIEPTS AND MILAGE DRIVEN FOR WARRANTY PURPOSES. __________________ I BELIEVE IN JOHN 3:16 Last edited by BCOWANWHEELS; 09-04-2009 at 10:43 PM.

09-05-2009, 02:35 AM	#12
Green Machine Senior Member Join Date: Jul 2004 Location: Estherville, Iowa Posts: 3,371	Re: New engine break-in Check out this thread - lots of good info - http://67-72chevytrucks.com/vboard/s...d.php?t=355062 __________________ 1968 C10 307 3spd Long Fleet ------ http://67-72chevytrucks.com/vboard/s...d.php?t=201103 1970 C10 305 Super T10 Long Fleet --- http://67-72chevytrucks.com/vboard/s...d.php?t=202285 1971 C20 383 TH350 Dana Posi ----- http://67-72chevytrucks.com/vboard/s...d.php?t=206894 2001 GMC Sierra 1500 C3 6.0

09-05-2009, 05:20 AM	#13
special-K Special Order Join Date: Nov 2004 Location: Mt Airy, MD Posts: 85,861	Re: New engine break-in For decades the recommendation has been break it in easy with no constant rpm/load.For decades motors had no problem making enough cylinder pressure to seat the rings.It`s all about letting everything seat itself.If it`s a manual the clutch needs to seat itself as well. In that thread someone said they use moly rings because they break-in faster.I was taught the opposite.Cast is softer and you want the rings to seat to the cylinder,not take material off the cylinder.The rings are the wear part.Moly is harder and will last longer and resist cracking better.I would use cast rings on a motor to assure a good break-in on a motor that I overhauled.I`d use moly on a motor I rebuilt and expected a long life from. I`m no expert,but that`s who I get guidance from.If I`m wrong I`m all ears. __________________ "BUILDING A BETTER WAY TO SERVE THE USA"......67/72......"The New Breed" GMC '67 C1500 Wideside Super Custom SWB: 327/M22/3.42 posi.........."The '67" (project) GMC '72 K2500 Wideside Sierra Custom Camper: 350/TH350/4.10 Power-Lok..."The '72" (rolling) Tim "Don't call me a redneck. I'm a rough cut country gentleman" R.I.P. ~ East Side Low Life ~ El Jay ~ 72BLUZ ~ Fasteddie69 ~ Ron586 ~ 67ChevyRedneck ~ Grumpy Old Man ~

09-05-2009, 05:36 AM	#14
AusMarty Registered User Join Date: Jan 2005 Location: Australia Posts: 215	Re: New engine break-in When I had my big block run in on the engine dyno the guy loaded it right up at full throttle but didn't let it rev above 3000 rpm, he did this three times and a total of 15 minutes in all, then we done two pulls one at 5000rpm and one at 6000rpm to see what hp and torque we got, the idea of loading the engine up and not letting it go above 3000rpm is to increase the pressure in the cylinders which forces the piston rings against their bores and bed them in, so if I were driving while running an engine in I would find some hills and load it up without reving it too hard to avoid glazing



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