Rixevo

hey guys! nice site you got going.

Well i am just after as much info as i can get regarding rotary engines.

I want to build one and was wondering what would be the best one for a learner!!
I was thinking about a 13b and start of by getting the housings, are all 13b housings the same? are all the parts interchangable?

cheers!

Aaron Cake

iTrader: (1)

All 13B housings are dimensionally the same, that is, they will swap in place so you can mix and match irons/housings. HOWEVER, emissions passages are not all the same, intake bolt locations/flanges may be different, and spark plug locations vary somewhat. Also, prior to '86 coolant seals were in a groove in the housing, then in '86 were moved to the irons. Then for the Renesis, moved back to the housings. Speaking of the Renesis, the housings don't have exhaust ports.

I don't suggest you start mixing and matching until you have a bit of experience.

Just to give you an idea of what the process is to rebuild a 13B:

These videos will help you in the process of rebuild a 13B or 12A engine. While they deal with an older 13B from an RX-5 Cosmo, the engine internals are basically the same for any 12A or 13B. The only real difference is that on engines newer than '85, the coolant o-rings are in the irons instead of the housings as shown in this video.

The first video is engine removal. While it is an RX-5 Cosmo, an car that few will ever see let alone work on, the process will give you the general idea of an engine removal. Steps are similar for most rotary vehicles, it's the details that differ.

http://www.youtube.com/watch?v=zgsbVp22pOE

The next video is engine disassembly and some cleaning. This is an old carbureted 13B so the accessories bolted to the engine are different than newer engines. However the process of externally disassembling any rotary is about the same. Covered here is also flywheel removal (same for any rotary) and engine parts cleaning.

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

Cleaning of all engine parts continues in this video. Provided here are examples of how this is accomplished with a minimum of tools and supplies. It's a lot of labor to clean old parts until they are looking new again. At the same time, parts should be inspected.

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

Finally, here is the engine assembly. This video includes clearancing side seals, assembling all the seals onto the rotor, then assembling all the parts into a 13B short block.

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

Rixevo

thanks for the advice aaron, i actually stumbled across your cosmo rebuild by doing a google search and then this site also came up, i have been watching all your videos, i am currently up to the "installing auto windows" at the mo and will probably watch the rest this weekend

Anyways back on topic..

So am i better just to buy a complete engine and strip it down and rebuild it to get more familiar with the process? and what one do you recommend?

I dont actually have a shell yet, for some reason i want to start with the engine :p
I do how ever want a series 1 rx7, i love the shape also i dont want a turbo, but if i bought a turbo engine is it hard converting to non turbo?

Aaron Cake

iTrader: (1)

Converting a turbo engine to a non-turbo just means swapping in the higher compression NA rotors, then finding an intake manifold to fit the 4 port block.

Any engine is going to be fine as a learning experience. Probably best though to find one that matches your car.

ThePlatypus

Ha I just watched those videos sometime last month while I was getting stuff for my research paper on rotaries. Gotta say, it was pretty distracting.

audoetuk

I know NZ has a big rota seen so try to make some meets & talk to owners...plus yall have ppre & Mad Mike, you should maanage lol

Rixevo

I have got my eyes on a 12a turbo motor its complete, the guy recons it has 20psi compresion in the rear rotor, so will need a rebuild, hopefully theres no major damage.

My question is, will i need to get higher compression rotors if i convert it to non-turbo?

Aaron Cake

iTrader: (1)

Best to use the higher compression rotors otherwise you are just wasting power potential.

A turbo engine with low compression on a rotor generally means apex seal damage, which generally means housing/rotor damage as well.