mmonaco

now that i got your atention, i have a question. When you get a new engine what are you breaking in on a rotary. Is it the apex seals, the rotor in the housing. I know that the cam is being broken in on a piston, so what is it? Thanks Marc

DomFD3S

I would like to say that I hate it when people make a random title in the post for the SOLE purpose of getting a member's attention. I am reluctant to post a reply to your thread, but I will nonetheless.

Now, back to your question. When you are breaking in an engine (regardless of type), you are allowing the multiple surfaces and seals to "seat" properly against each other. In effect, this allows the seals to do their job, basically "seal". It is not just any one area in particular. All of the parts in/on the engine are forming a tight seal against itself. If you are talking internally, you could say that the apex seals are wearing themselves into what you can say, their proper or normal seating area. (I only used the apex seals as an example. It is more than just the apex seals). Kinda like new shoes. When they are new, they are stiff and hurt like hell. But as you wear them more, you wear a certain distinct pattern in them. This pattern also shows where your foot would typically be at. Same idea.

mmonaco

thanks for the responce. Marc

Piston Pete

mightyslash

ianewk

...but this is what I was told by the rotary god of Europe...if it had to "break in" then it's not sealed, and the compression would show it as a bad engine.

I know this is an age old argument, but it begs the question...is break in really necessary?

I think the argument stands to this day because nobody is willing to gamble a few grand on finding out. WELL I AM AND I DID!!!.

On the knowledge of what has been aforementioned as the rotary god of Europe...and I say this because Mr. Frey owns the premier Mazda dealership in Europe and has at least one of every rotary vehicle EVER made (this includes prototype Citroen rotaries that never hit the market gentlemen...bet you all didn't know that!), and everything from pristine Cosmos to a couple of FDs...when he did my swap I asked him out of common knowledge what the break-in period should be. His response..."There is no break-in required. Break-ins are held over from the days of bad machining and imperfect design...everything now is CAD and lasers. If the apexes needed to be sealed, it's a bad engine, period."

If I blow my engine before the norm I'll eat my share of crow...if not, I hope it sheds some light on the break-in argument.

FLAME SUIT ON!!!!!

user 84205

You know I have a buddy with a 12AG I think it is. He wanted to see if this was true about the break in period, he does his rebuilds for pennies... So it put it all together, and jumpes on the gas a little, he said there was no power at all, just bogged, and he went about another 100 yrds and BOOOMMMM!!!!!! there goes that engine.... So I would have to say a break in period is NEEDED......

I know even on aircraft, we have to do like a break in type thing too. When to metal objects will be rubbbing togther, you need that time to them to work to EXACT specs.... Thats something to cant grind, or sand before the engine is put together....

JoeD

i hate it when people do this ****.

i feel that there should be a new rule for the forum that says thread titles to get attention should not be allowed.

i think Johnny should get rid of these types of threads, or at lease edit the title.

rynberg

If no break-in is necessary, why is it repeatedly proven that cars get faster as they get some miles on them? Albeit this is with piston engines, but all the car mags that do long term testing have found many times that the car is faster at 10000 miles than new. Also, I'm sure some members can attest to the fact that compression improves during the first 1000 miles or more.

yy4u

I know BMW might not be the rotary god of europe, and i know my car has pistons, but those guys over there in germany are pretty sharp and they told me that the engine in my 330 needed to be broken in (not over 4500rpm or 100mph) for 1200 miles. From personal experience with machines on a smaller scale, i'd have to say that i believe break in periods serve a purpose.

jspecracer7

You are breaking in the oil seals. Letting everything heat up and cool down so everything seals right.

...and PLEASE do not make stupid threads like this again

user 84205

nicely put JSPEC haha

jspecracer7

I think he should have put the title as "Engine Break in questions?" or "Engine Break in period"

user 84205

oh, very much agreed..... I think from everyone....

ianewk

The proof is in the pudding so to speak.

I'm not foolish enough to slam on the gas and tear out of the shop that did my swap at 12 psi with a cold engine...but I did run medium/hard in the first 2000 miles (with low boost) on the autobahn.

Some say oil seals, some say rotor housing, some say apex seals, some compare apples with oranges (or pistons to rotors)...

I'm really not rabble-rousing here...
...I merely seek the definitive answer on the break-in question, not regurgitation of "common knowledge".

Hmmf, I guess we'll see.

But don't be suprised if you see a post from me in about 50,000 miles saying DAMNIT DAMNIT DAMNIT!!! You guys were right!

RedR1

iTrader: (5)

the pistons in yer FD are located in your brakes.