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How long for a break-in period for a new motor?

  • Thread starter Thread starter 95CobraMike
  • Start date Start date Aug 25, 2005

95CobraMike

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Apr 12, 2004
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Aug 25, 2005
#1
  • Aug 25, 2005
  • #1
built a new 306 with rings and bearings, wondering how long break-in period i need to do before "normal" driving
thanks
 

Grn92LX

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Aug 25, 2005
#2
  • Aug 25, 2005
  • #2
Click this link and follow Barry R's response. You're broken in now Just come home and change the oil and drive it as you normally would. Just check for leaks and odd noises before you take it out.


http://bbs.hardcore50.com/vbulletin/showthread.php?t=12510&highlight=engine+break
 

Pokageek

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Jun 10, 2005
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Aug 26, 2005
#3
  • Aug 26, 2005
  • #3
They told me to take it at variable speeds until 1k so I figured that was the definition of "break-in." They also said don't change over to synthetic until 1k miles or so. I am at 450 miles now and run it hard on occasion. No problems.
 

Grn92LX

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#4
  • Aug 26, 2005
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Who is "they"? I switched to synthetic @ 500 miles which was fine after I asked Mark O'neal From probe/chp.
 

95CobraMike

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#5
  • Aug 26, 2005
  • #5
whats wrong with synthetic oil right away?
 

BlueOvalStangGT

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Oct 27, 2003
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Aug 26, 2005
#6
  • Aug 26, 2005
  • #6
Something about glazing cylinder walls?
 

Pokageek

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#7
  • Aug 26, 2005
  • #7
They meaning the engine manufacturer (precision engine out of Texas)
 
H

HUNTED

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Aug 2, 2005
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ENID, OKLAHOMA
Aug 26, 2005
#8
  • Aug 26, 2005
  • #8
Your engine is broke in after 30 mins of start up. Either the rings are gunna seat or they arent. When you have your block bored they glaze the walls of the block in order to break the glaze you have to run a non synthic oil to do so
 

Rootus

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Feb 8, 2003
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Aug 26, 2005
#9
  • Aug 26, 2005
  • #9
HUNTED said:
Your engine is broke in after 30 mins of start up. Either the rings are gunna seat or they arent. When you have your block bored they glaze the walls of the block in order to break the glaze you have to run a non synthic oil to do so
Click to expand...
+1
 
W

wytstang

Mustang Master
Mar 14, 2004
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Summerville,SC missing South Fl. weather :(
Aug 26, 2005
#10
  • Aug 26, 2005
  • #10
Hunted is correct.
 

95CobraMike

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#11
  • Aug 26, 2005
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sweet action so when i first started my engine i had regular oil in it.... i started the engine, warmed it up reved it up a few times (to 3k) ket it idle for a while and then shut it off and drained the oil and put in synthetic, its been about 300 miles since and it hasnt seen even 1 pound of boost yet.... so all that taking it easy for nothing
 

Redsnk95

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Aug 26, 2005
#12
  • Aug 26, 2005
  • #12
As the racers say, after you back if off the trailer its broke in. In all reality I do initial crank-up on dyno oil, to help the bearings. After that back to Royal Purple.

Troy
 

Grn92LX

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#13
  • Aug 26, 2005
  • #13
95CobraMike said:
sweet action so when i first started my engine i had regular oil in it.... i started the engine, warmed it up reved it up a few times (to 3k) ket it idle for a while and then shut it off and drained the oil and put in synthetic, its been about 300 miles since and it hasnt seen even 1 pound of boost yet.... so all that taking it easy for nothing
Click to expand...

Thats incorrect. You really needed to go out once the cars running/driveable and put a load on it. Too late now though.
 

ROLLIN5.0

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Nov 19, 2004
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Tulsa, OK
Aug 26, 2005
#14
  • Aug 26, 2005
  • #14
The regular oil is supposed to break the glaze from honing, so that the rings can properly seat. That is quickly accomplished by putting a load on the pistons. If you are at 400+ miles, break-in is way back in the rearview, where you can hardly see it. Go ahead and drive it like you stole it, and run whatever oil you were planning to switch too. It amazes me how many engine builders give bunk instructions on how to break it in.
Brandon
 

95CobraMike

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Apr 12, 2004
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Aug 27, 2005
#15
  • Aug 27, 2005
  • #15
so the consensus is that you have to take it out for a drive and put it under load before it is ready for synthetic?
 
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