(Engine) Video: 13B Rotary Engine Rebuild
 

As part of my '76 Cosmo project, I just built a 6 port 13B NA engine and posted the entire process to YouTube. I then realized that the video applies to basically all 12A and 13B rotary engines, so I'm going to also post the video in the 1st, 2nd and 3rd gen forums for anyone who is building a rotary.

If you've never built an engine, or are just about to, then you want to watch this video. Covered is the entire build process of a 13B rotary including: measuring rotors, clearancing side seals, assembling all rotor seals, assembling the short block, setting eccentric shaft end play, assembling the "under the front cover" stuff and finally installing the front cover as well as torquing the front hub bolt. As far as I know, this is the only full process free rotary rebuild video out there. This video, combined with the Haynes/FSM manuals, should enable anyone to be confident in putting together their first engine. While the engine shown in this video is a hybrid engine made from both RX-5 Cosmo and GSL-SE parts, the steps covered are the same for any Mazda rotary from 12A to 13B-REW.

http://www.youtube.com/watch?v=ijJeUk_GqiI

Enjoy!

i'm moving this to a sticky!

Great video Aaron

Awesome video Aaron, I just watched it start to finish. I must say, I find myself wanting to drive as fast as I can to pick up some Royal Purple Max Tuff Engine Assembly Lube..... and I can only imagine the looks at wal mart when I'm checking out with a cart full of vaseline and shop rags! Thanks for taking the time to record the assembly, and sharing the video.

Ya know, that's probably not unusual for the typical Wal Mart customer. ;) But you need a kid strapped to your back and your baby-mama needs to push the cart wearing her old ballet costume. Now that's a proper Wal Mart customer.

Dude, that was great. Thanks a ton for making and posting that! Im gonna be rebuilding my first engine ever soon (12a from a GSL), and that is an awesome resource. Lots of shit missing from they haynes manual (like the color coding on the oil control ring springs) that you covered.

Also, your entire cosmo project seems slick as hell. Thats something to be proud of. What an awesome car.

"people of wal-mart" fan are you?? Seriously, that was a great video. :icon_tup:

Nice video, Im sure many will appreciate you taking the time to do this :bigthumb:

Fantastic video. Me and my boys are about to attempt our first rotary rebuild. This video definitely makes me feel more comfortable about it.

amazing video man. i just got my engine pulled and in the garage wednesday and am about to head out to start tearing it down. i watched this so i could have an idea on what to expect with the tear down. amazing timing too.

I am so glad someone did this fixin to rebuild the ole 12-a backup engine in a few weeks !!

Glad you enjoyed the videos!

These two may help as well. They cover engine disassembly and cleaning. The engine which is taken apart is a 13B from a 76 Cosmo, but it shares many similarities on the external equipment with a 12A. And of course, the internals are the same as any late '70s to present rotary.

Disassembly:

http://www.youtube.com/watch?v=W1MXfs_Srs4

Cleaning:

http://www.youtube.com/watch?v=U5A5q61bzRI

Hell, if you want to do some porting, I have that too. Just use whatever templates you prefer:

http://www.youtube.com/watch?v=y1Gy5sVMK3o

i watched the first 2 videos just before going out to work on it and except for the thermal reactor everything was the exact same. one question though, did you use any kind of stop when taking the flywheel off?

When you use an impact gun, a flywheel stop is not required. I generally just hold it by hand.

Hmm.
FD corner seals in the 76 cosmo rotors.. really?
*shifty eyes*



edit: Fail on my part. Im assuming these must be newer cosmo rotors? But then how are you comparing the apex seal grooves with the GSL-SE rotors?
I guess I should have paid better attention. Ive confused myself. :(

No, he IS using the 76 Cosmo rotors with FD corner seals

'76 cosmo 13Bs have 2mm apex seals? fo real?

Still confused.
In that case how would the apex seals interchange with the GSL-SE rotors in the measuring demonstration?

Corner seal springs- OK... but corner seals? mind-f***!!

I said "seals" in the video when I meant to say "seal springs". They are obviously not FD corner seals because early 13B rotors are 3MM while FDs are 2MM. They are, however, FD corner seal springs. It is actually harder to fit the FD corner seal springs on 3MM rotors because there is less wiggle room in the mouth of the spring. The springs need to be positioned just right to allow the apex seal to slide in.

aha!! thats what I thought :)

Anyways, I should have also mentioned that its a great video!


Thanks for sharing your adventures with us!!! :)
Two thumbs up!

The only thing I could see to improve was showing a close up on the corner seal springs..Great Video Will definatly use it on my 79-7 finally got the turbo on the other day cranked it up and got the blue smoke of death so time for a seal kit and Thank You for sharing the Video for the rest of us!!!!!

Yeah, I had intended to get a few closeups on the corner seals but in the heat of the moment I kind of forgot. Actually I got distracted because one of the brand new OEM coolant o-rings was cracked right out of the box and I had to dig around in the gasket bin for another...all the while the sealants were drying and time was ticking away. :)

He he just fly on down here to good ole HOT Louisiana and help me rebuild my 12-a and I'll forgive you:lol:

Man sick build mate. Thats got me ready to rebuild my next engine instead of being lazy like ive been the last few months. :egrin:

Great Video man. This is going to be really helpful in the near future. Do you know of any decent rotary shops in the London area? I can't find any down here in Sarnia, So this video is definitely gonna bail me out of trouble i think. ha ha :icon_tup:

Amazing video I liked the detail and subtle (or not so subtle) humour bits :D

I DO remember criss cross. They've never made me jump though like they said. Numbering those bolts was genius! Why no cheezy automotive porn music like in the atkins vid? :icon_tdow (jk)

Vernors FTW by the way!

I am going to take a look at that porting vid next ^_^ I'll be saving this to my HD for future reference if you don't mind. Cheers and thanks for this!