Break In For new Motor
Thread Starter
On The Tree
Joined: Nov 2001
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From: Washington, D.C.
Break In For new Motor Just re-did the bottom end of my stock 346. For the first fire-up planning to:
drain any left over antifreeze and fill enignine and radiator with hot water,
fill the crankcase with 10 w 30 detergent oil, start engine and run for 25 to 30 minutes @ 2,500 rpm, occasionally pushing up to 3,000 rpm.
Shut off motor and let the car sit overnight,
then change oil, filter and refill antifreeze the next morning;
go to the track and hope that the rings have seated properly.
This is a track only car, so no chance to drive on the street. Any suggestions/ experience would be appreciated.
Thanks,
Chuck
drain any left over antifreeze and fill enignine and radiator with hot water,
fill the crankcase with 10 w 30 detergent oil, start engine and run for 25 to 30 minutes @ 2,500 rpm, occasionally pushing up to 3,000 rpm.
Shut off motor and let the car sit overnight,
then change oil, filter and refill antifreeze the next morning;
go to the track and hope that the rings have seated properly.
This is a track only car, so no chance to drive on the street. Any suggestions/ experience would be appreciated.
Thanks,
Chuck
TECH Senior Member
Joined: Nov 2001
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From: Mississauga, Ontario
Re: Break In For new Motor Thread Starter
On The Tree
Joined: Nov 2001
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From: Washington, D.C.
Re: Break In For new Motor Thanks for the link. Very interesting. Not sure that I agree with everything this guy says, but he makes some very valid points. I wish he could have been a little more specific on exactly "how hard" to break in...with some rpm numbers. I had already planned to vary the rpm higher, just not sure how much is too much.
Anyway, thanks again for the help.
Chuck
Anyway, thanks again for the help.
Chuck
TECH Enthusiast
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From: CLARKSVILLE,TN
Re: Break In For new Motor The best way I know is to start the engine and keep it at around 1800 rpm until it warms up then go out and punch it from 2000 to say 4500 rpms with it in second gear once or twice. Then park it, let it cool and change oil, tighten up header bolts etc. Then normally I'd say go easy for 500 or so miles, but for a drag car I guess I'd just give it hell.
TECH Veteran
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From: Ft. Lauderdale, FL, USA
Re: Break In For new Motor What the hell does he mean by this sentence?
"The pressure takes the path of least resistance, which means it passes over the top of the ring, and gets behind it to force it outward against the cylinder wall."
If the pressure passed over the top of the ring and then behind it, it would force it outward, FROM THE WALL AGAINST THE PISTON. Wouldn't it?
"The pressure takes the path of least resistance, which means it passes over the top of the ring, and gets behind it to force it outward against the cylinder wall."
If the pressure passed over the top of the ring and then behind it, it would force it outward, FROM THE WALL AGAINST THE PISTON. Wouldn't it?
TECH Resident
Joined: Jan 2002
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From: dallas,tx.
Re: Break In For new Motor </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Quickin:
<strong>What the hell does he mean by this sentence?
"The pressure takes the path of least resistance, which means it passes over the top of the ring, and gets behind it to force it outward against the cylinder wall."
If the pressure passed over the top of the ring and then behind it, it would force it outward, FROM THE WALL AGAINST THE PISTON. Wouldn't it?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">no. when the piston reaches TDC the ring is seated on the bottom of the ring groove with some clearence on the top of the ring that will allow the pressure of combustion in behind the ring and force it outward against the cylinder wall as the piston assembly travals downward.
initially some gases might get by, but that is why you have two rings, both acting in similar fashion.
clear as mud now?? <img border="0" alt="[chug]" title="" src="graemlins/gr_chug.gif" />
<strong>What the hell does he mean by this sentence?
"The pressure takes the path of least resistance, which means it passes over the top of the ring, and gets behind it to force it outward against the cylinder wall."
If the pressure passed over the top of the ring and then behind it, it would force it outward, FROM THE WALL AGAINST THE PISTON. Wouldn't it?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">no. when the piston reaches TDC the ring is seated on the bottom of the ring groove with some clearence on the top of the ring that will allow the pressure of combustion in behind the ring and force it outward against the cylinder wall as the piston assembly travals downward.
initially some gases might get by, but that is why you have two rings, both acting in similar fashion.
clear as mud now?? <img border="0" alt="[chug]" title="" src="graemlins/gr_chug.gif" />
Thread Starter
On The Tree
Joined: Nov 2001
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From: Washington, D.C.
Re: Break In For new Motor I agree that some of his statemtents were a little over the top and geared more towards motorcylces. I do think he makes a valid point, though, about a limited amount of time using the cylinder wall crosshatching. he never really speaks clearly about an rpm range, but I've heard that I should keep rpm above 2k.
Chuck
Chuck
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From: Ft. Lauderdale, FL, USA
Re: Break In For new Motor Well, the mud is a little less cloudy. <img border="0" title="" alt="[Smile]" src="gr_stretch.gif" />
Whats your opinion, you may have read my thread about this. I'm having my new ARE 436ci installed next week, the shop is 150 miles away. Should I drive it on the highway for its first 150 or trailer it home and do it in the city?
Whats your opinion, you may have read my thread about this. I'm having my new ARE 436ci installed next week, the shop is 150 miles away. Should I drive it on the highway for its first 150 or trailer it home and do it in the city?
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Verdad Gallardo TECH Resident
Joined: Jan 2002
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From: dallas,tx.
Re: Break In For new Motor The highway would be okay, just vary your speed/rpm's occasionally. hit the frontage roads from time to time. rebuilds break-in alot faster than new engines, so don't be too nervouse about pushin it a little bit. also, when you get it home do an oil change into a clean pan and see what comes out. always better to catch any potential problems as soon as possible.
good luck with the new mill!!! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
good luck with the new mill!!! <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />
Staging Lane
Joined: Nov 2001
Posts: 68
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From: Sydney, Australia
Re: Break In For new Motor Any chance of them running her in on an engine dyno. This is the best way I know of. It can be cycled under controlled conditions over a preset program. Then just bolt her back in and away you go. Well worth it the extra cost .
TECH Fanatic
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From: pa
Re: Break In For new Motor he is talking about bikes, and that is my thing, have a shop and worked at them for years. BULLSHIT!
I have and know many others who have seized bike motors due to getting on it too soon. those are tight tolerances at first, heat = expansion!
can't believe everything on the net.
I have and know many others who have seized bike motors due to getting on it too soon. those are tight tolerances at first, heat = expansion!
can't believe everything on the net.
TECH Veteran
Joined: Dec 2001
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From: Ft. Lauderdale, FL, USA
Re: Break In For new Motor </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by 8POTS:
<strong>Any chance of them running her in on an engine dyno. This is the best way I know of. It can be cycled under controlled conditions over a preset program. Then just bolt her back in and away you go. Well worth it the extra cost .</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No engine dyno, but he has a regular dyno that he'll be using when everything gets installed.
<strong>Any chance of them running her in on an engine dyno. This is the best way I know of. It can be cycled under controlled conditions over a preset program. Then just bolt her back in and away you go. Well worth it the extra cost .</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">No engine dyno, but he has a regular dyno that he'll be using when everything gets installed.