I had a couple of days off, so i decided to use them to try and learn something more about the rotary. I've never been into one before, although i've spent alot of time reading threads of people who have, so i figured it would be a great way to learn.

I have a jspec in my car right now, which means the one it displaced has been sitting in my garage since then.

THE MOTOR:

It had coolant leaks or any mechanical problems, but the rear rotor had a 0psi compression reading, while the front rotor had about 20psi.

All apex seals are INTACT

Coolant seals were fine

I set out to see if i could figure it out.

 

All the seals appear smooth and scoring doesnt look bad enough to cause that bad of a compression leak.

MOST of the side and corner seals were stuck, so there's a good chance that was the culprit.

After examining the rotor housings more closely, i notice that the smaller piece of the apex seal had worn a nasty groove alont the edge of the housing... (second picture shows this if you can see it well enough) It looks ugly, is this common? The pictures may be hard to make out, i took them with my phone because my camera is in my girlfriends car

I'll probably have to replace these housings, right?

 

Opinions?

Also, the haynes manual isnt very descriptive about resurfacing the irons and i dont want to go filing through the pdf on my slow computer: does removing metal from the irons cause problems with clearances? I havent looked very closely yet at where the e shaft sits, but wouldnt it run into something if you made the engine slightly shorter?

 

I don't know for sure, but I would say that those housing are ok still. I have yet to finish rebuilding my TII engine, but my one housing looked like that and I intend to reuse it (I had to replace the other housing, someone lost a washer down the intake and the engine died with 1200 miles on a fresh rebuild.)

 

Those parts are worn, but from what I can see it's rebuildable.

Port it & put in some 2-piece seals - yummy.

 

I was thinking of bridge-porting it! mmm... and i was also thinking of 2 piece seals as well. If I'm right, the atkings kits come with 2 piece seals right? maybe i'll look again. and s6 corner seal springs and such.

Has anybody else ever taken apart a motor with no compression W/O a failed apex seal?

 

Hard to tell from those pics about the rotor housings...
If the grooves aren't too deep, reuse them.
Just make sure you don't flip them around.

How did the apex seal springs come out?
Can you measure them?
If they are flattened (overheat or detonation), that could cause the low or no compression even though apex seals are intact.

The apex seal wear looks like minimum 60k to 80k miles...or even more.
How much miles on that motor?


-Ted

 

I have no idea how many on this motor...
This motor was in my car when i got it, and my car has 180k, so its apparently not the original. I dont know much about this car's history, but this engine doesnt look like a rebuild to me. Maybe a used low mileage donor or something like 8 years ago...

Apex seal springs didn't look that bad actually, havent measured them. But a few of the side seals were completely stuck, as well as the corer seals. Corner seal springs look very bad.

 

the side seals likely got stuck from the car sitting for a while, some MMO probably could have brought it back to life but too late now.

 

hm, oh well! I need to get some experience rebuilding anyway. plus, its better to rebuild BEFORE losing an apex seal, rather than after.

Thanks for everybody's opinions!