Here are some pics of a customers motor that I just tore apart.



Rear Iron

Attachment 19281



Attachment 19282



Rear Rotor

Attachment 19283



Attachment 19284



Center Iron

Attachment 19285



E-shaft

Attachment 19286



Attachment 19287





Front iron also had some heat marks and damage to the edges of the rotor as well. All apex seals were intact and the housings where not damaged either.

The rear rotor bearing definatly spun, it was working its way out of the rotor....



This motor had 12,000kms on it. No visible blockages, no metal shavings in the oil either, the motor smelt very bad when coming apart, like burning death!



Any ideas why this happend? Over revving? crappy oil? oil cooler lines plugged?



Either way, he's getting a completly new motor lol.

I thought the troops would be all over this??????????



Anyway the bad smell ov overheated oil is a help. The fried irons is a help. The corner seals do not appear to have been dragging on the iron. So, the rotor stayed fairly square (parallel) with the irons.



Whenever you build an engine you must seat the rotor gear with a press or a big block of aluminum and a big hammer. Set the rotor on a piece of aluminum plate on a strong surface and whack the aluminum plate on the top real good. Or if hitting things with big hammers is below you, put it in a press and give it a good hard push.



You can measure it first if you like but it surprises me how many used rotors have the gear walked out a bit when I get them. That distance is controlled by the land area on one side and the thrust surface on the gear.



I run a DA (orbital sander over the both side to increase the clearance a bit and put the orbital sanding marks in the metal, so the next time you see it, if those marks are gone, the rotor has been touching the irons again. Take off a couple of thousandths from each side. Take at least .005"off the side of the rotor around the corner seals. In a lathe with very sharp tooling (So you don't wipe metal across the seal grooves)or with a DA and fine paper.



When you remove material from the thrust faces, the rotor can tip more without touching anything. If it can tip further the corner seal area can touch also. So you reduce it also.



So. if you miss a shift or select the wrong gear on a downshift, you could scream the engine and get away with it. Leaving only the rotor bearing loading as the last failure point.



If the rotor appears very clean on the combustion face, it may have detonated and load failed the bearing.

But the oil would only overheat that was actually in the bearing at the time. So, a big bad smell when you open the pan is more likely oil too hot for the load on the bearing.



The center of the irons fried indicates the rotor got to be too long and was dragging on both sides. So it ran for a while with the rotor dragging but not the corner seals. So the bearing failing and the rotor stopping were sparated by some amount of time, long enough to boil some of the oil, and crack it into some lighter foul smelling crap. Some ends up like lighter fluid, and some turns into black snot.



To further fog the situation, the bearing may have held up for several trips prior to failing totally and the event that failed the bearing may have been further back in history. Then a week later while zipping down the freeway, the engine goes soft for no appearent reason.



Very generally, when you see all of this and the corner seal area dragging, It all happened at once, and the driver knows damn well what the cause was. When in a case like this you have one of the symptoms but not the other, you may be reduced to guessing what happend, and or how far apart the events took place.



I have been gifted running engines with over stressed bearings turning gleafully inside the rotor and the engine running just fine. The bearing walks out the gear side and stats getting machined away. With very little bearing supporting the rotor. But you can limp around like that for a while.



Remember that big oil pressure is to move heated oil off of the bearing at a higher rate (faster) so as to keep the bearing overlay cooler. Because the silver looking stuff has a low melting point. Note that damage seems to stop at the copper layer? Note that some people machine off the silver stuff (about .001" thick) when building the engine because the copper makes a real good bearing surface, and is very strong and has a high melting point. Did you not think of that before?



On the other hand this information may be worth what you are paying for it. Or even less.



Picture is from Mid Ohio.



Lynn E. Hanover

i agree with lynn....



actually i took apart a motor that looked just like that, and i found that the front cover o ring was pushed out

I took one apart that was a Hayes rebuild. It looked like that. The owner was showing off for some friends and while reving, the oil line blew off (found a washer in the front oil pressure reg). The oil lines were replaced with new AN braided lines but the engine locked up after a while. I tore it down and the first thing I noticed was the oil pickup tube had fallen into the pan. The side seals were welded to the rotor. The front stationary bearing was welded to the shaft. The side plates looked just like the pictures above.

Front Eshaft bolt fell out on this one at full boost. Car was towed in and would actually start, very nice engine sound however https://www.nopistons.com/forums/pub...IR#>/smile.gif

N3C1-11-408 is a little plate that goes over the front pulley bolt, and mechanically holds it in place

^^^^NICE^^^^^ I actually was looking for that P/N recently!