Break in and oil consumption

DeeVeeEight

DeeVeeEight

Fast Pedalphile
Joined
Nov 3, 2008
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Location
Southern New Jersey, USA
How long does it take for everything to seat and seal internally in a freshly built 383? How much will spirited driving affect oil consumption? What is considered normal oil consumption during break in?



:ill:
 
:friends:

I'm in the same boat. Looking forward to responses.

How much are you buring now?

Also how do you define spirited? :crutches: I took my son for a short run yesterday and fishtailed to about 60 degrees. Would that qualify?
 
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i've never been able to do a rebuild that didn't burn a quart every 1000 miles.

and it wasn't really my fault. the machine shop bored it too big.

so to answer your question, chances are that its not going to get any better.
 
All I can say is that every damn engine I have had the lower ends bored, pistons, balanced, assembled.....has burnt oil like mad for the first ~2000 miles or so....dunno why, typically 4-5 quarts, the first quart at maybe 300 miles....

makes me wonder WTF GM/any company does for break in, so the customers don't bring every damn one back with oil problems....I would suppose they run the fuck out of them.....one way or another....stick them short blocks on a electric motor for a day or two?? maybe long blocks with no spark plugs in there??:search::shocking:
 
mrvette said:
All I can say is that every damn engine I have had the lower ends bored, pistons, balanced, assembled.....has burnt oil like mad for the first ~2000 miles or so....dunno why, typically 4-5 quarts, the first quart at maybe 300 miles....

makes me wonder WTF GM/any company does for break in, so the customers don't bring every damn one back with oil problems....I would suppose they run the fuck out of them.....one way or another....stick them short blocks on a electric motor for a day or two?? maybe long blocks with no spark plugs in there??:search::shocking:
Click to expand...

I have been wondering about that too. How do they do it? Is it simply better quality control? Better parts?
 
Back in my dealer days (daze?) warranty wouldn't even talk to anyone that used less than a quart in 500 miles.

Depending on the rings that are installed, they can seat anywhere from 100 miles to never. I built several with chrome rings and never had any problem. Rebuilt a 534 Ford with Hastings rings and it made a great mosquito killer. No idea why. Pulled it apart again and installed someone else's rings and it dried up like a prune.
 
The current method of break-in is to give the engine a quick 15 minute elevated rpm no-load run for cam break-in. Once the cam is okay, the engine should be given several hard pulls (either on the dyno or by making a few WOT runs through 2nd gear). This creates high cylinder pressure and forces the rings to seat against the cylinder walls. Once this is done, the engine is broken in, the rings are seated, and there should not be any noticable oil consumption. I've done this on all my engine builds and I've never seen any detectable oil consumption. With the cam broken in and the rings seated, we then take the engines right up to redline and run the heck out of them with no problems and no oil consumption.

Lars
 
I don't know. I go back and forth on this issue.

Why don't new cars need any break-in? There's nothing in the owner's manual about it. I don't buy these these brutal sandpaper hone jobs done to seat rings. I don't understand with the tight manufacturing tolerances we have today why the bore would not be polished and mated perfectly to the rings before the engine ever turns over.
 
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lars said:
The current method of break-in is to give the engine a quick 15 minute elevated rpm no-load run for cam break-in. Once the cam is okay, the engine should be given several hard pulls (either on the dyno or by making a few WOT runs through 2nd gear). This creates high cylinder pressure and forces the rings to seat against the cylinder walls. Once this is done, the engine is broken in, the rings are seated, and there should not be any noticable oil consumption. I've done this on all my engine builds and I've never seen any detectable oil consumption. With the cam broken in and the rings seated, we then take the engines right up to redline and run the heck out of them with no problems and no oil consumption.

Lars
Click to expand...

I have about 5k miles on the engine, would it still benefit from the above WOT runs through 2nd gear or is it too late?
 
lars said:
The current method of break-in is to give the engine a quick 15 minute elevated rpm no-load run for cam break-in. Once the cam is okay, the engine should be given several hard pulls (either on the dyno or by making a few WOT runs through 2nd gear). This creates high cylinder pressure and forces the rings to seat against the cylinder walls. Once this is done, the engine is broken in, the rings are seated, and there should not be any noticable oil consumption. I've done this on all my engine builds and I've never seen any detectable oil consumption. With the cam broken in and the rings seated, we then take the engines right up to redline and run the heck out of them with no problems and no oil consumption.

Lars
Click to expand...

:nuts: THAT is the SAME thing I used to hear from older drag racers back when, I did it to one engine over the years, no problem, but the rest being basically street machines, they never got that full a treatment right outta the box....no problem after a few miles either....

BUT, I have attempted two short block engine assy's in my life, and neither one turned out well, I tried to tell a my welder friend that I did not like doing that sort of work, but he cajoled me into it, it did not work, LOOKED good going together from anything I knew about.....but a month later it was outta there and 4 grand later it was back in.....a backwoods NASCAR type engine shop did it....located off a rather funny named...THUNDER ROAD......:rofl: ....
 
DeeVeeEight said:
I have about 5k miles on the engine, would it still benefit from the above WOT runs through 2nd gear or is it too late?
Click to expand...

You have 5K on the engine and you haven't yet run the car at WOT...? If it's still burning oil or smoking, the cylinder walls are likely glazed over at this point from not having been run hard, but I've had some limited success in taking an engine with rings that have not seated and hammering it hard for several runs to get the problem somewhat corrected - you want to force the rings into the walls as hard as possible to get them to seat, and you can only do that by running the car hard.

Lars
 
lars said:
DeeVeeEight said:
I have about 5k miles on the engine, would it still benefit from the above WOT runs through 2nd gear or is it too late?
Click to expand...

You have 5K on the engine and you haven't yet run the car at WOT...? If it's still burning oil or smoking, the cylinder walls are likely glazed over at this point from not having been run hard, but I've had some limited success in taking an engine with rings that have not seated and hammering it hard for several runs to get the problem somewhat corrected - you want to force the rings into the walls as hard as possible to get them to seat, and you can only do that by running the car hard.

Lars
Click to expand...



my engine rebuild was treated too easy by me at first and there was some oil consumption during the first several thousand miles, maybe 1 qt per 1500 miles....especially with the 700r4 the engine really never saw high RPMs.....then my kid took it to college with him during our move from NJ to VA and the car came back to me with even less oil consumption.....then I changed the carburetors and in the process changed the PCV routing and the tubing and the manifold nipple.....now there is no oil consumption.

I am attributing the change to exactly what Lars said... the engine needed to be loaded up to build cylinder pressure to seat the rings and my misguided ideas of breaking it in easy just prolonged the break time, and the college kid didn't have my same set of sensibilities..... I also think that having the PCV valve plumbed into a large diameter manifold vacuum port didn't help things out either.
 
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I have to ask was the block torque plate honed ?? as we just went through this with guy that had his 327 engine rebuilt and was complaining about the oil getting black in 100 miles and I did a leak down test and we found ring seal was a big problem, The best cylinder was 10% the worst was 40% and the average was around 20%

When he brought the engine in the shop we putt the torque plate on the deck and when it was torqued up we found the cylinders on the average were .003 out of round and you could actually see where the rings were not even touching the cylinders.

So far the engine has been running well and the oil is now staying clean.

If it was plate honed there is not much break in and if not tring to get ring to seal with bores distorted up to .003 its going to be a long time to get then to seal.

Here is a god link on plate honing I did a few years ago.
http://www.camaros.net/forums/showthread.php?t=58964

One other area we have seen problems with is with Valve seals as we have seen problems with the white teflon seals as that maybe an area to look at and make sure your PCV system is correct.
 
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