I just blew my rebuilt motor! Its only been a few months and not long after I had it fine tuned with an Autronic. I pushed 1.2 bar and it blew at 7000rpm. My question is, after I blew the 1st rotor, the second rotor is showing only 50psi on each bounce. Is this right? Is this a sign of another type of seal blown? I know the 1st rotor is blown because I only get one bounce, but that's at 50psi also. I'm in the process of taking out the motor but wanted to know if this might be an obvious sign that someone might've seen before. There hasn't been any fluid mixing in my coolant or oil so I can't figure it out. I'm worried that when I take apart the motor, I won't be able to figure it out either. Do you guys think this motor is not rebuildable?

 

Any 13B is rebuildable, it just depends on what parts need to be replaced

The second rotor thing is wierd since all the faces show only 50psi.. I can't explain that. With the first rotor blown you may have to replace the rotor and housings if the seal did any damage.
Anyone who knows how a rotary works, how it builds compression, will be able to tell what went wrong with the engine apart in your situation. Its gotta come out anyways, post pics of the dissasembly if you still can't figure it out.

 

Thanks. I just thought of something. If I blew the water seal, could that be why I'm getting the 50psi compression? If I did blow the water seal, is that probably due just to the high temp or could it be because of a bad rebuild or bad housings? I did push the car to where it was super hot but what temp would the water seals go at? And I don't know how to tell if my housings are bad in terms of coolant passage seals. Maybe my housings are messed up, could that be it too? I would just hate to rebuild this motor and it happen again.

 

How hot did you get it, exactly?

 

I would try a different compression tester, something doesn't sound right with 50 psi being the highest on both rotors. I suspect the tester is leaking somewhere.

 

About 116 degrees Celsius or about 240 degrees Fahrenheit. I know, pretty bad because my 3 row front mount intercooler is blocking all the air. The motor still ran strong but I noticed a super small leak after on the top of the block. It look like it was coming from where the lower intake manifold met up with the block.

 

In my opinion, this is very bad. Coolant runs through passages, wich in turn feed the turbo through a metal hose that is atached to the LIM. Now if coolant is leaking from the LIM after your engine was heated up and not before, that tells me that the irons/housings expanded to much becuase of the intense heat, and you warped the flange on the LIM or something.
anyone else think so?

 

did you break-in the motor properly? seeing how you just got your motor rebuilt a few months ago, improper break-in period and 1.2 bar of boost will easily blow the keg up.

 

chipped apex or stuck side seals on the second rotor, blown on the front, and stuck seals as well on the other face. Happens a lot.

 

Wow, everyone hear is awesome. I just got home from work and am pulling the motor tonight. I hope everything inside is ok. I did break in the motor but maybe not enough. What was hard was that I had the autronic put on right after I did the rebuild so the first thousand or so miles was a basic map that wasn't fully tuned. After that, we burnt the rest of the miles on the dyno, then tuned the crap out of it. It basically took us 7 hours to get the tuning right cause we kept uping the boost and the transition between the 550 and 1600cc injectors were tricky. I already have an upgrading cooling system but I don't think its getting enough air because of the intercooler and I have my 3 MSD ignition boxes up front. I'll probably move those and make more ducting and this time break in the motor a lot longer. Maybe 3mm might be better also?? A lot of people say Mazda OEM are better but does that mean using the older rx-7 3mm seals because there are no listings for our cars stock right? Man, this is fustrating because I actually wanted to get a bigger turbo. I was maxing out the Greddy TD06 at high rev (exhaust side too small). Between .8 bar and 1 bar, my max hp didn't go up, only the mid range shot up. Actually, when I was at .8 bar I had 315whp, but at 1 bar it was at 310. Anyways, rambling huh? I guess since you guys reply so quickly I figure I'd better get in everything before I get off the comp. Hmm, maybe water injection?

 

I'd like .8 bar.

 

50psi?? You should be getting close to 90psi. The break in for a rebuild should be around 500 miles, some shops say 1000 miles with factory apex seals, with ceramic seals is minimal but I can't say since I've never used them.
A friend of mine that has what was the fastest 13BT FC in the world until a few years ago (Rafaelito from Falito Racing in Puerto Rico) used factory apex seals on his car. Problem is that they are VERY expensive and if you break with ceramic seals usually the housings die too, good thing....they can handle a LOT of boost.

 

i read there is a more advanced way to break in then just a drive in period ....

- first couple hundread miles stagger rpms and rev to about 3k
- next couple hundred stagger rpms and rev to around 5k
- last couple hundred same thing and go to redline once in awhile

cant remember where i read that ... but the site had more exact details