Reply With Quotehey i would run about 4 hours to let every thing get seated and then change you oil about after 5 hours so you get all the assm. lube out . that is what i have done on my past rebuilds and it has worked great. http://free.***boat.net/ubb/biggrin.gif
What is the typical time required to break in a new set of rings and what RPM's should I stay below during the break in period? I just finished putting forged pistons and rings into my std bore 460 BBF and was wondering. Thanks. Tim
hey i would run about 4 hours to let every thing get seated and then change you oil about after 5 hours so you get all the assm. lube out . that is what i have done on my past rebuilds and it has worked great. http://free.***boat.net/ubb/biggrin.gif
i ran mine about 1 hr but be sure to vary the rpm and dont lug the motor picked mine up to 45oo in bursts then back down to 350-3k.
Were the rings installed with a lot of oil on them? If so, three hours or so is plenty. Just remember to vary the rpm. If they were put in dry, 25 minutes to break in the cam and you're ready to rock.
Mister460,
I oiled up the cylinder walls to ease the installation and provide protection for initial start up. Should I have skipped the oiling? Running it for a few hours prior to opening it up and seeing what it will do is no big deal any way. I have already done the cam breakin on the trailer. I don't think my neighbors would appreciate three hours of ring break in on the trailer, so I'll do that on the first trip.Thanks for the input. Tim
Below is the recomendation from Hastings web site. You can relate mph to rpm and get the general idea. Hope this helps.
BREAK-IN PROCEDURE
1. Make a test run at 30 miles per hour and accelerate at full throttle to 50 miles per hour. Repeat the acceleration cycle from 30 to 50 miles per hour at least ten times. No further break-in is necessary. If traffic conditions will not permit this procedure, accelerate the engine rapidly several times through the intermediate gears during the check run. The object is to apply a load to the engine for short periods of time and in rapid succession soon after engine warm up. This action thrusts the piston rings against the cylinder wall with increased pressure and results in accelerated ring seating.
Wow, there are as many variations in break-in suggestions as there are replies to this post...may I offer my two cents?
To begin with, use a high grade, petroleum-based motor oil for break-in, because the synthetic lubricants have such a high film strength that your rings most likely will not seat. Get a good quality oil filter that has a fine particle filtration rating stated by the manufacturer (they rate in microns--there are 1000 microns in a millimeter).
Beavertim, I am assuming you rebuilt your entire bottom end with new bearings, etc. I don't know how much you've invested financially, but I'd think that the more money you have into it, the more care you will take in your break-in.
This can be a casual thing and it can also get very EXTREME.
It has been argued that the majority of internal engine wear (over the entire life of an engine) takes place the first time you start your motor. I am not sure of the scientific accuracy of this claim, but in some of the more expensive motors I've built, I changed the oil and filter after the first five minutes of operation. Then once again on the second start-up from cold all the way to operating temperature. And again after an hour of running time with load on the engine.
I realize this is very extreme. (The last engine I did this with was an overhead cam automotive motor that had a 10,500 r.p.m. redline and we weren't taking any chances; you don't need to do this.)
With the little info I have on your motor, I would first recommend a good quality oil and filter. Over a ten hour break-in period, vary your engine speed. Also, for the first couple hours of running time, do light load running with 1/4 to 1/2 throttle. The next couple of hours, run it about the same but with short 3/4 to full throttle bursts. Gradually increase this activity over the ten hour period. Change your oil after five hours and once again after the full ten hours.
Hope this helps,
LO
Tim, oiling the cyllinder wall is okay on assembly. I always take a clean rag with some ATF on it and wipe down the cyl walls. ATF is almost pure detergent so it helps clear the metal flakes from the rings on startup. Yes, metal flakes. The only things that really "break in" on an engine is the cam, the rings, and the vlave seats. That's it. Bearings, valve guides, rockers, timing sets, etc. don't. Anyone that tells you otherwise is mistaken. And all that break in happens in the first hour of operation. Unless you make the mistake of oiling the hell out of the rings. Then it might take a while. Give it 30 min of run time above 2000 rpm to break in the cam. Change oil and filter. Run for another 30 min taking it easy. By easy I mean no extended operation at any one rpm. Go ahead and give it a couple WOT burns down the water, just not for a long time, i.e., vary rpm. Then, life as normal. Do your next oil change at half the normal interval, though. Then change as norm.
Many thanks to all of you for your helpful insight and recommendations. Tim
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