Hi im really considering getting a new mazda block for my 87 T2. But I havto break it in wich sorta bothers me. i heard you cant run any boost until like atleast 500 k and that they are not good on aircare right away until it fully breaks in , whenever that is. if anyone has got a new mazda block share your experiences please. Maybe i dont know what im getting myself into

 

You have to properly break in ANY freshly built engine, brand new or reconditioned. Keep it under 4000rpm, absolute minimal use of boost and no long trips at constant speeds. Do this for around 1000km.

 

damn i was thinkin of goin on the freeway for a day. but i guess not. after 1000 k can you start going nuts ? oyea when you break in a engine what actualy happens inside the engine ?

 

i thought you were suppose to break in your engine like your gonna drive it? thats how it is for dirt bikes anyway, but i'm sure i'm mistaken

 

NZ convertible and others...

Ive been building a few engine lately and I usually use old housings, so nothing is all that tight. I tell the customers to keep it under 4k for the first 500 miles, then change the oil, then raise it up to 5k, change the oil again at 1500, then do with it as they will. Ive had good success so far, and the engine seems to develop to all it should be around 2500 miles.

ANyway Ive heard several times, off and on, not to drive on road trips at near-constant rpms. Why is this?Ive never heard of anyone having ill effects from doig this on a new engine, so Im looking for other engine builders' thoughts here.

 

That's good advice. I forgot about the oil changes, they're important. Any thoughts on "running in" oils?This is something I've heard dozens of times but never with a good engineering explanation. I sure there is one but I don't know it! I did a quick Google search and found this page on proper engine break-in procedures which says to avoid constant road speeds, but not why.

 

I got a headache trying to read what you're trying to say...



-Ted

 

Change your oil after about 500 miles to rid of foreign contaminants. You don't want to redline until everything has seated in. After about 1000 miles do another oil change and gradually redline during shifts. If you installed a new clutch, that takes time to break in as well. If you drive on the freeway most of the time, the clutch will take longer to break in. Compression will be somewhat low but will gradually increase during break in. I don't understand what " breaking in an engine sorta bothers me". Oh boy. I hope you don't go boosting on a cold engine.

 

The "don't use constant speed" thing is more a piston engine thing than a rotary.

But in essence it is my understanding that if you use a constant speed (such as 55 MPH or 2500 RPM) the break in occurs at an engine speed that is not constantly used.

So things like valve springs or in our case Apex seal springs are not tensioned evenly over the whole operating range of the engine. Same idea for the piston rings or apex seals. The contact area is theoretically the same, but the pressures and tempatures applied are different based on engine speed/demands.

Now if the engine was to run at only 3500 rpm day in and day out like some of the hybrid electric/rotary test mules, then yes the constant speed break-in would be what you want.