Check this out - cracked corner seals
 

So about 6 weeks ago I lost my motor, after going back and forth on rebuild options I decided to take the time off from work and rebuild it. I found some very interesting things upon tear down and I was wondering what your opinion might be as to how these things happened.

Motor background:
04' with 110K on the clock, has run 5w-30 Royal Purple and Idemitsu premix since 38K. It was driven hard on occasion but it was mainly a DD with mostly highway mileage.

All of the corner seals on the rear rotor's front face were cracked.

The front iron looks like it tried to port itself but I'm curious as to how.

The front rotor is beyond beyond repair one of the apex seals was completely gone and there was no trace of it at all but the little piece of that apex seal was still there. The other apex seals are there but they are a part of the rotor now. That rotor also had these marks on the front face.

The side seals were in good shape but the springs had disintegrated (I have to say that those pieces are INCREDIBLY sharp), there was basically no spring tension on the seals.

Here is a pic of the front stationary gear bearing - All the bearings looked fine for the mileage on the motor. I was expecting them to be heavily worn given what others have experienced with the higher mileage motors.

Thoughts??

looks like something was seriously eating away at the housing wall -- pic #2... guess we know where your seals went!

Looks like it lost an apex seal in the front rotor and as it went for a ride it did alot of damage to the rotor and port on the face of the front iron.

I would bet that when the front rotor blew it put extra pressure on the corner seals of the front of the rear rotor. Here is how I would guess it affected it: I would suspect that the apex seal floating around and getting lodged cause the shaft to flex a little putting the pressure on the rear rotor and breaking the corner seals.

I have been wrong before.

The only way to crack the corner seals on stock ports is w/ pressure outside of combustion pressure.

Good luck rebuilding it.

No, no, no.

Your supposed to put a title up like "5w30 DOES CUT IT. Pics of good bearings after 100k!"

And then sit back and watch 50 pages of carnage.

:lol: :)

anybody want to talk about the side seal springs?
How the heck does apex seal get pass a side seal?
from what I can see is--not much carbon buildup at all?
Thanks for sharing this OP.
Little more history?
Redline limit--temps--??

Rotary Inspired -

That makes sense, but on a totally stock motor? The rotor housing was scratched up quite a bit but the plates themselves weren't at all.


LOL, well I was contemplating posting them in the synthetic oil thread, bring the popcorn!



I'm confused as well OD, I was thinking that those marks on the side of the rotor are from that piece of the side plate but it's on all three faces. I was expecting those plates to be ruined from what I've heard about the renesis when a seal fails. There were NO scratches, or marks of any kind on them. The apex seal appears to have disintegrated, there was a fine powder in the exhaust port. Might be a question of what came first.....the seal failure or the side plate failure.

Yea, the carbon that was there came off very very easy. The rear rotor had more but it wasn't built up badly. The exhaust ports had a good deal of carbon buildup though.

Redline was stock @ 9000, quite a few times it went to the fuel cut off @ 9500

Temps - It saw from -10 to 110F, and I used 5w30 the entire time. Sometimes I would let it warm up, but most of the time I would start it and wait until the rpm would drop down and then drive off (30 seconds max). Oil was changed ~3000


Any other questions, or if you want to see more pics just lemme know as I took quite a few.

more rotory porn please

Interesting. Any mods? Any overheating incidents? Any milky oil problems? What was the amount of premix added? What do you think your average commute leg was? Oil consumption?

While the 5w-30 seems okay for the bearings, it seems in this case the 65k of pre-mix didn't help the seal wear.

Here ya go:

1st is the rear iron
2nd is the carbon buildup in the exhaust port
3rd is the front rotor front face
4th is the middle iron front face
5th is the eccentric shaft


I have more on the camera but it will have to wait till later when I can get the usb cable.

No mods to the motor other then reliability ones....BHR Fuel pump and ignition...

No overheating that I'm aware of, though this past summer it did get hot enough for the temp gauge to move and I know that it's not the most accurate thing in the world.

Only the normal milk on the dipstick in cold weather.

It varied from no less then 4oz up to 8oz per tank. For the past 2 years I have been adding 8oz per tank.

The average commute varied over the years. It was anywhere from 3 miles up to 45, but has been at 45 one way for the past 2 1/2 years. Those 3 mile commutes the car barely even got warm by the time I was where I needed to be.

Oil consumption was about a quart every 3000 miles. It remained roughly steady the entire life of the motor.

oh man that exhaust port is pretty nasty. all of them like that?
OD

Subscribing. There are tons of marks on your rotor faces and side housings. Ouch. It's unfortunate to see the premix didn't help your apex seals. :(

This makes me want to strip my motor apart and see whats going on. I see there isn't much that is salvageable. I would like to know what ate away at your rotors like that. That carbon build up is pretty intense as well, did you ever seafoam the vehicle?

OD - Yes they are

Shaun - That pic of the rear iron I like because it shows the wear patterns very well, but they really aren't that badly worn.

Doc - The rear and center plates are reusable, they have around .002" of wear on them which makes them a little more then halfway through their usable life. The rear rotor is also usable. I would like to know as well, there were no pieces of the damage causing agents left so I don't really know.

I was under the impression that the stock apex seals don't disintegrate when they fail, looking at the dead rotor it really looks like something hit the apex seal making it bend over into the rotor and caused it to fail, the next apex seal in line was cracked but remained in it's groove, the third was hit by shrapnel but didn't crack. They are however permanently jammed in their grooves. Looking at the damage done I'm kind of leaning towards the plate having a failure. I'd really like to hear opinions on that.

I'll get pics up of the damage to the rotor and housing in a little bit.

Okay here's some more pics of the ruined rotor and that rotor housing. Yes those scratches are as deep as they look.

Also the third pic is of the rear housing, wanted to show that there were no cracks at the spark plug holes.

Yikes, thanks for sharing. I'd like for the experienced builders to chime in.

dude--i really think--on seeing that rotor face--that a seal didnt do that.
Plate failure makes more sense to me?
That would somewhat answer the side seal spring mystery also?
Which came 1st seal or plate--dont know.
No cracks around the spark plug hole--lots of seal skip going on--you liked rpms?
OD

^ What do you think it's going to look like with a whole metal apex seal running around loose in there?

;)

wow i can't believe that it's scratched up so badly!!

hopefully you can figure out what caused.

Yes I do OD :) it sounds so glorious.

The apex seals were worn more in the middle, which I don't get since I was premixing....makes me wonder if 8oz isn't enough??

I am glad I am doing 1oz per gallon, hopefully it helps.

dan--that is a large amount of bad gashes? Plus he couldnt find any of his apex seal that broke off and the 2 parts off his plate had to go somewhere?
I have never seen one that scarred. Yall have probably seen more than I have so tell me --would one apex seal cause that much damage that fast?
Why did the side seal springs disintegrate like that?
OD

well if thats the case the question would be did the apex seal wear down, or did the apex seal split a piece off. If the apex seal had a piece break off then MAYBE its feasable, but I would think this was something else because the seal could have found the path of least resistance. Speaking of which.

Did you have a cat on the vehicle? have you checked inside the exhaust for any more pieces of the engine?

Then you haven't looked around enough! lol

When my last motor came apart from a bad front stationary gear bearing, the front rotor was practically round instead of triangular.