broken corner seals
 

What causes this to happen ,two corner seals were broken on the front and rear rotor,does porting play a role in this and oh yeah one corner seal was stuck inside the rotor we had to break it to get it out.

well, my best guess is that the engine had overheated or it's OMP had failed at some point ...

Have any pics? I know the rubber insert melts away alot. I always thought it was a dumb idea to have a rubber insert on something that gets as hot as the rotors.

I had a rotor where I couldn't get the corner seal out. It had a coolant leak on that rotor.

Diabolical1, I saw a pic of a rotor housing that had a working omp. The apex seal going past the oil injection hole leaves a distinct pattern on the housing, and it didn't look like the oil was getting spread out more than and inch and a half. I could be wrong, cause I'm not 100% sure how the corner seals get lubed. I plan on running pre-mix when I get my engine together.

no pics
 

I took the rubber inserts out and i was using premix ,oh yeah its all 3rd gen parts installed ,.

Its a 3rd Gen motor, or 3rd gen corner seals in a different model motor?

use solid corner seals..... they wont break ever!!!

solid corner seals
 

I am using 3rd gen corner seals in a 3rd gen motor,what you mean solid corner seals ,i thought all corner seals were solid once the rubber insert was taken out.

i think he may be referring to the corner seal that don't use the rubber inserts ... however, i'm not sure where you'd get them for a post-'86 engine. the only ones i know of can only be used on engines with 3 mm apex seals.

Got pics? The only ones I know of that don't use the rubber insert are these found at mazdatrix.com for the pre '76 rotary engine.

Sounds like a temperature problem, combined with a oiling problem, i know the corner seals like to get coked up with carbon, also the rubber melting can be cause by blowby and also insufficeient rotor cooling, which is a problem on the 86-92's with a the e-shaft bypass plug, which seems to be a chronic failure point..Max

those were actually the ones i was referring to. though i have no way to confirm this (because i didn't actually see it) i've heard of them being used in engines up to '85.

Here is a pic of the corner seals with not rubber insert.
http://www.mazdatrix.com/pictures/b-engprt/cornearl.jpg Those are marked pre '76.

I bought the e-shaft plug that replaces the original thermal plug, the one allows oil to flow through the e-shaft all the time, instead of waiting til the oil gets up to a certain temp.

are those 2mm
 

Are the corner seals before 76 all 2mm .

I don't know, it doesn't say. The only corner seals Atkins Rotary has listed for pre '76 is 3mm. Mazdatrix sells the 93-95 corner seal springs as a better proformance springs in place of the OEM spings for all years 74-92.

yes ... most apex seals '85 and older (North America) are 3mm ... i believe there were some that were wider on the REALLY early engines ... i'm tempted to say 5 or 6 mm ... but don't quote me on that.

however, everything that's '86 and newer came with 2 mm seals.

This is the stock corner seal spring from 74-92 (2mm)
http://www.mazdatrix.com/pictures/b-engprt/sprgcorn.jpg

This is the 93-95 (2mm) which will fit 74-92 as an upgrade.
http://www.mazdatrix.com/pictures/b-engprt/spgcorrc.jpg

I have these for my 87 motor I'm working on. What I would recommend to London is that you email Mazdatrix and see if the '76 corner seals are 2 or 3mm and whether or not they will fit your motor. They are usually good about answering email. If you ever try to contact atkinsrotary, you have to call them, they don't answer email for shit.