any body go any fact based tips on engine brake in? the old manuals say go slow for so many miles. id like to know for my 40' flathead but allso for my late model shop truck, any differance?
I like to rack up some easy freeway miles to loosen a fresh motor up a little... Pick somewhere about 100 miles away that you'd like to be, and go there and back about five times (not neccessarily in one DAY or anything!)...check all bolts and hose clamps and such everytime you park the car, and change the oil after the fifth trip. Just like that, you're Disco!
I've had old timers tell me to go real easy on them for the first few hundred miles. and i've also had old timers tell be to break in the cam, then beat the living shit out of it. seems they both work just as well. just look at a top fuel motor. they hit the thottle a few times, run it for a few minutes, then they are ready to make a pass. about the only recomendation i can offer that doesn't conflict with anyone elses tried and true method is to run the motor at 2500rpm for 20 minutes to keep the cam covered in oil during it's break in period. after that, seems like the thing to do is either take it real easy, or drive it like a rental car. just don't drive it like you would your daily driver. four-thirteen
Actually, to break in the cam you want to vary the RPM between 2500 and 3500, cuz the cam lobes only get oil from splashing, so you want to try to keep the oil splashing all over the place. I just bought some stuff from Total Seal called Quick Seat. It's a dry film lube that you put on the cylinder walls. They claim that when used properly the rings will be fully seated after 5 minutes of running. It's kind of expensive ($25 for 2 grams), but I'd spend WAY more than that in fuel driving 500 miles!!! With this stuff, once your cam was broken in and your oil changed, you'd be good to go! One thing that always made wonder though... I was pretty good friends with my engine machining instructor, and I helped with the motors for his roundy-round cars. We would put together an SBC, put it in the car, fire it, time it and put it out for 100 laps at 8200rpm, and win!?! never broke the cam in, never seated the rings, and the motors would usually last a whole season! Engine break in... fact or fiction? you tell me.
I know it's not quite the same, but I've got a friend who used to race go karts. He'd build his engine, fire it up, drive the piss out of it and be faster than any other car that was broken in like you'd expect it to be. He drives his dailys the same way. "If it's not to the red in first, it's not driving." Derrick
Spent a lot of time taking with tech guy at total seal ring about a set of rings that went bad .He told me to break it in with non detergent oil.
proper break in for most internal combustion engines (exc 2 stroke karts) are usually achieved by... -soak rings in WD-40 before head installation. -do NOT run syth oils during break in period. -do NOT just drive the car 500 miles on the highway as 'break in' miles. -do get a good 500 miles of nice, easy stop and go miles. the rings seat better with varying amounts of throttle rather than crusing on the hwy (close to 0 ins of vac) as far as cam break in goes... HotRodToHell has the right idea. personally, I hardly ever break in a motor with a new aftermarket cam. I usually use the old one then, install the new one. HTH
I've heard the non-detergent oil thing, but I have never understood why??? I was always told to do a lot of acceleration/deceleration cycles on a new engine, its supposed to help the rings seat. Now I'm curious. Does anyone know what the advantage of non-detergent oil is?
from what I understand its the same deal as synthetic oil... the detergent makes it TOO slippery, so there is not enough friction to seat the rings properly.
[ QUOTE ] just look at a top fuel motor. they hit the thottle a few times, run it for a few minutes, then they are ready to make a pass. [/ QUOTE ] Thats apples to oranges. They are constantly tearing the thing apart. Dont they replace everything after X number of passes, even if it looks ok? Check this out: http://www.mototuneusa.com/break_in_secrets.htm . You'll spend hours looking at all of the other articals on the site too. You still have to break in a cam by running it at 2500-3000rpm for 20-30mins and varying the rpms the whole time (like Hot Rod to Hell said).
ive used a bunch of differnt cams and directions very but the just of it is run at around 2500 rpm 15-30 min, flathead probely less critical,cause of low spring pressure i shut it down imediatly after cam break-in and dump oil, then drive it varying rpm wind it up a few times and back out of the throttle, than normal driving , change oil 500, 1000,2000 ,3000 than normal oil change schedual, i change the flattie every 1000-1500 though
[ QUOTE ] Thats apples to oranges. They are constantly tearing the thing apart. Dont they replace everything after X number of passes, even if it looks ok? [/ QUOTE ] i agree on this one... you cant compare a top fuel engine to a street engine. what i did seems to have worked fine. 30min breakin time for the cam, varying the rpms between 2-3500rpm, a friend checked for external leaks and tuned the carb/distrib. while i sat in the car monitoring the vital signs. i also adjusted the valve lash a tad loose, then tightened them up after the cam run in... no particular reason other than not wanting to grind a 3rd cam. we then took it out on the freeway and tried to seat the rings by taking it up to 5000rpm then coasting it, rinse repeat several times. then went to a parking lot and whipped some doughnuts. what made it interesting for me was the hills... iam surrounded by steep ones. on the way back home on a particularly busy HILL, i broke a couple rocker studs which were stock components... bad idea if you are using a higher tension spring.
3 or 4 months back,I built a 408 cu in stroker, based on a Mopar 360 Magnum engine. FULL roller engine. Took it to an engine dyno so we could break it in,and get some idea as to hp and tq. We fired it,warmed it up for about 10,15 minutes,varying the rpm and only putting a light load on it. Shut it down,changed the oil/filter,checked a few things then fired it up. Got it up to temp and started the pulls. Made a total of 10,back to back pulls,2 grand up to 6000 rpm. Only stopped long enough to mess with the timing and a couple of jet changes. Engine got stronger on each and every consecutive pull,AFTER the timing and jets were corrected. Moral of the story? This being a roller engine,there really was no need to worry about cam break-in,but, it does take a while for the rings to seat in though.You can actually see the difference it makes,in the numbers! If you ever get the chance to run an engine on a dyno,or even be with someone else when they do a dyno session,by all means do it. Very educational and it is fun as hell to be able to thrash your engine without worring about the cops.......
Without question, it is pretty easy to ruin a new camshaft. The alloys used in modern engines and the supporting replacement parts today, somewhat change the old mindset used to break in a fresh engine. This is what I do and it was taught to me by a pretty darn good engine builder. I use the manufactures cam lube and I leave the inner valve springs off. I start it and run it for about 20 minutes at different RPMs, not to exceed 2500. Shut it off, put all the valve springs on, change the oil and filter and then go out and run it any way you want to. There is no mystery in seating rings. If the cylinders are round and honed properly, the rings should seat properly the instant you start the engine. If they don't, your going to have a problem that will never cure itself. Flat heads might be different, never had one, don't ever want one. Shoe
I break the Cam in by the accepted methods, but as for the rest of it, "Break 'em in the same way you intend on running it" was what I was taught.
I just finished breaking in my 351W crate motor and it took 7000 miles !!! I used the normal cam break in procedure stated above but I used regular multigrade 10-30 oil for the first 1000 miles and switched to synthetic. The engine burned a quart every 500 miles. I finally went back to a 15-40 multigrade and took it on a 400 mile trip running it at 3000 rpms all day long. When I got back,it was perfect,no more oil burning.Obviously, the statement above about not enough friction was probably right. I have put 2000 miles on the engine since then and the oil is still full and it doesn't smoke anymore.
"the statement above about not enough friction was probably right" I know its right. Back when Slick 50 first came out, I had about 500 miles on a newly rebuilt 355. I decided to change the Break-in oil and add Slick 50. I put about 20K on that engine before I sold it and the Rings had still not seated.
In MI it's usually like $500 to rent the dyno for the day. more if you want them to tune it for ya. Most people won't need it for a full day though, so it's like $100 an hour or so... the new speed shop opening by me is gonna charge $150 for 3 pulls on the chassis dyno, with tuning in between. So I'm figgerin about $300 should get me pretty close to where I want to be...
[ QUOTE ] "the statement above about not enough friction was probably right" [/ QUOTE ] good info guys. so thats why after 300 miles my 85 toyota(o/t) shop truck smokes lightly on start up. ill try the 15w40.
I dont know after forty years of buying, selling, hauling,blending, loading, unloading,slipping,sliding,pumping,going to semimars of three major companies over the years, and spilling more before breakfast than anyone else here when it comes to oil, but check out my post in reply to Deyomatic on Jan 23. After cam break in, go out and hammer that motor from 30-40 mph to 80 mph and coast down. Repeat a dozen times and then change oil to what you run and drive like you had it for years.
Everybody is talking about whether to break in, when to break in, how to break in, but noboady has asked WHY to break an engine in. Is that because everybody here KNOWS about how the average manufacturers machine everything to a cheap and sloppy 'near enough' fit and finish, to save money and sell more cars/parts, and how you have to run 'em gently pretty much for a couple hundred miles to wear down all the lumps and bumps, tight bit and bad fits. Or is it just because nobody thought to ask about it? Run an engine in too soft, and you'll glaze the bores and burn oil forever. Do it too hard, and you burn up bearings and rings, cams and followers. Do it right and your motor will last for years
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