H_PersÆng

I bought a 12A about a month ago for the price of 100$ (pretty cheap imo). There is alot of work to be done like an engine revision and some rustgrinding before it will be roadworthy ofcourse....but all in all not to bad, seems like the wheelarches are completely rusted through and there is some rustholes on the bottom to the rearside of the car, dented fender and some engine trouble like a busted startermotor and such.

Tell me i did a good deal

I finished revising the engine now....i didnt get a chanse to take it appart completely because i could by no means in the world unscrew the big bolt that goes all the way through the engine and where the flywheel is attached to.

Seems like the problem with the startermotor was a simple wire wich was almost completely broken...

I clean out the carb and cleaned air filter, resealed the cartercasket.

Put new belts on it, fixed the exhaust collector, fixed the oilcooler...also cleaned out the fixed and cleaned out the ingnition a bit...

I had a few questions of stuff wich seems very weird to me....this is the first rotary i ever put my hands on so there is some stuff i dont quite crasp....

First of all...

What the hell does the airpump do?? :s

i was taking apart the engine and came across a part wich i had first mistaken to be a weirdlooking waterpump....but it wasnt, no im really wondering what its for...it seems to go into the inlet....

Is this some kind of prehistoric compressor or what am i looking at here?

second....

There seems to be an unused beltwheel....there also seems to be an unused set of bolts....i could not figure out what these where for....am i missing an engine part here or is this spot simply for possible optional addons like powersteering?

Also, the nr2 compressionchambers egnition wires where switched....the trailing was switched around with the leading wire...the previous owner of this car never noticed any problems with the engine and how it was running (actually he was convinced it was a 5 cilinder engine) so im wondering....whats up with that? Shouldnt it be running like a dieseltrain with the ignitionwires switched around?

I also welded the exhaust collector...it had a hole in the side and i closed that up....it also seems like there is another plate on the inside of this collector...this plate seems to be totally broken into several pieces...is there any harm in this? I was planning on pulling out the interior broken plating to prevent it from clanking while driving since its broken anyway......does this plating have any significant use or is it just for noisedamping or something?

My final question....is the big bolt that goes all the way through the engine (where the flywheel is screwed onto) right screwed or left screwed? I been janking and pulling it for about 4 houres with all sort of levers and stuff in both directions but it wont even budge :s

The engine is nice and cleaned up now and fixed (i hope). Aside from a few things that are beyond me it should run fine now (unless it has no compression ofcourse).

That was another thing i noticed....the engine doesnt seem to have much compression....meaning you can turn it by hand if you turn the flywheels. i can just turn it around....i can hear the rotors suck and blow but i dont feel the compression.....is this normal?

Well anyways i hope itl run when i put it back in....im fixing the body now, after that its the interior...

Btw....howmuch hp does a 12A have? Its completely stock. Right now im just a little worried about the compression....since i dont know howmuch compression these engines are supposed to have :s. So yeah.... i dunno howmany miles it has...the dash shows 75000 kilometers.....but it doesnt have a 6th digit so there is no telling howmany times it went round already hehehehe

Btw howmuch would i need to pay for a block with decent compression?

djmickyg

WOW long post. cant belive i read it...
anyways now i gota answer..

the air pump, pumps air..
to the exhaust were via the magic of television turns the bad gasses into good.

the missing bolts? are these on the side of the engine with the spark plugs?? these are prople where the air con pump gets bolted to and thats where the extra pully and belt go too.

and the big bolt is sure dam hard to break! that thing is torqued like no other bolt! when looking at it, it should unscrew like a normal bolt. ( thats anti-clock wise i think )
have u got a socket that big to fit over it??? or u hacking into it with a hammer and chissle?


and..... last of all the the 79 rx7's are usally the import jspec ones. and they have a little less power because of the smaller carb but there still got aroung 100hp. the compression should be above 95psi (i think)

and dont look at the km on the dash.. i got a 79 and its had 4 engines now that i know off. so who knows how many km the engine i got now has done???

H_PersÆng

Cool thx for the reply......sry bout the long post, i tend to do that :s.

About that bolt.....i wasnt trying to unscrew it at the flywheel side and exactly because of the reason i dont have a wrench that fits it....i would even think about hammering it off as that could prove catastrofic considering the amount of leverage i been putting on the other side of it.....

I'm actually trying to get the bold loose at the side of the pully. I tryed using a wrench with a metal pipe over it of about 1.5 meter and it didnt even budge !

The only thing that moves is the car when i pull that wrench.....to hammer the flywheels nut woudl probably result in a very fucked up nut that will never come off again...And i'm fearing compressionproblems so sooner or later itl have to come off nomatter what (have no idea how though).

The thing is.....the guy that used to drive it sayd it was running like a gem and was very fast....but it stood there in his backyard for about 6 months so that means it hasnt run for about 8 months....could 8 months of no running be awfully bad for this engine? I heard these engines dont take kind to not running for a while...

Im still not quite sure what you mean by that turning bad air into good.... Is it something that helps the exhaustfumes pass standards or something? Or does it really do something for the engine except make it more enviromental friendly?

And what about those switched ignitionplugs? Doesnt that cause the engine to run bad? The formal owner sayd it ran fine....but they were switched around....seems heller weird to me....right now im getting the feeling like this engine will prolly never run...lol

Anyways thx for the help, any other imput would be cool.

djmickyg

in the burnt exuast fumes lyes carbon monoxide, a bad gass, which causes water eyes, and light headedness as well as making a hole in that ozone layer..
with help from the catlitic converter in the exuast systems. this carbon monixide is turned into water vapour which is less harmfull for everyone..
it does this by.. in the cat there is is miles and miles of metal honey comb mesh wraped up in it and its all zinc coted, the air pump feeds cold air into the cat to help the cemical reaction (air is the catalits) between the monoxide and the zinc..

the car can run with out this nooo worries, and will run better. i havent got mine running anymore and im sure thats the same with 70% of the people here.

djmickyg

forgot to answer the other questiong about the sitting rotary..

of course the guy would tell u it ran like a gem, he wanted to sell it.

and no rotaries dont like sitting around for long periods because the rotary are oil cooled and the oil that sits around the roaties cant drain out back into the sump like oil in a piston engine would. so sitting around for a long time the old tries up and sezzes the rotor...

and one more this, i duno if u said this in the first post cus it was ages since i read it.. had u tried starting the engine b4 pulling it apart???
dont pull it apart unless ur sure u need to.. other wise ur gona have to start replacing unesseary seals that u didnt have too..

H_PersÆng

I did try to make it run but it wouldnt. It was willing...kinda stuttering but it wouldnt go....

We tryed to get it to run by hooking it up to a van...in the process of this the oil cooling radiator poped out from underneath the car and got a hole blown into it (DOH!) Also after some yanking there was suddenly a grinding noise wich later turned out to be the coplingplate wich is totally KIA now....i replaced already.

Like i mentioned earlyer....i didnt pull appart the engine completely, i took off the carb, alternator, air pump ignition ect....so i basically had nothing but the assembled block, i cleaned it up and did the same for the deassembled parts....i cleaned up some nasty rust and repainted here and there but basically just cleaning, some welding and some rewiring here and there.

Basically the block itself hasnt been open and is just the same as it ever was. I replaced all the seales of the parts i took of and added sealing goow to make it really really sealed :p.

About that guy who sold it to me....well hes not lying, its a friend of a friend and he confirms the old guys story that it ran very nicely....the only problem he had was the rust, the old guy wanted to fix the car but never got around to it so my friend (who has a scrapdealership) took it off his hands with the entention of selling it for parts.....so i bought it from him.

Id like to add that i was not the one who hooked it upto the van and totalled half the car that way just in case you were wondering if i would be that stupid :p.

So basically the deal is....the car ran fine, but my friend totalled the oilcooler and the coplingplate with his van (and the fender two)....so i fixed that and i fixed some things that should have been fixed ages ago aswell.

So basically it should run....

Im just puzzled by the ignitionwires that were switched around and i am questioning if the exhaust collector (the box located right underneath the carb) will still function properly seeying as the interior plating is broken and the exterior plating had a big hole in it (welded).

Im just wondering what this exhaust collector is for basically. I wouldnt want it to catch fire or anything because of the damaged platework.

ps: thx again for your replys

Wankelguy

'79s don't have catalytic converters, what you have is called a thermal reactor. Unburnt gas from the rotary engine's incomplete combustion enters the thermal reactor's inner chamber, where it is mixed with fresh air from the air pump to complete the combustion within the thermal reactor. Air is also pumped into the outside shell of the thermal reactor to keep it from overheating. It sounds like the thermal reactor is toast, due to the inner chamber being all broken like you say. You will probably want to replace it with a header anyway. Then you can ditch the air pump, and air control valve on the side of the intake manifold as well. If the thermal reactor is retained, the air pump must also be used to avoid overheating the thermal reactor which can have severe consequences. The flywheel needs to be locked somehow to facilitate removal of the front pulley nut. That "bolt" that goes all the way through the engine is the eccentric shaft, the rotary counterpart to a crankshaft. The front pulley bolt is usually loctited in place and takes some doing to get it broke loose. The flywheel nut is a 54mm nut torqued to 300-350 ft/lbs. and can also be difficult to remove.

H_PersÆng

Damn, thats alot of accurate info m8....

There is a few things though.....

The airpump does not pump into the collector i was talking about.....there was a heatshield over this collector wich was doubleplated (and also toast btw) and had one tube going up to the airfilter...the airpum basically just goes into the inlet of the engine and sucks from the airfilter....thats all it does...

The collectorbox i was talking about also has (aside from the main exhaust pipe) a smaller pipe heading to what looked like a catalytic converter.....i had to cut this pipe because the nut wouldnt come off the collector box...

Damnit i wish i payed better attention in mechanicclass :s

BUT here what im gonna do...

This typing about engine parts isnt really working so im going to go get a cam now and post some pics of what im talking about....that will make things much easyer...

What your saying looks like it makes sence but there are a few things that dont match with the parts i have lying around here so il just make things easy and post some pics...

Sry bout being such a troublemaker :p

thx for the help, il have pics here soon!

Wankelguy

I found a very simplified diagram which details the routing of the air from the air pump. The cooling air for the thermal reactor actually comes from the air control valve (ACV). What looks like a catalytic converter is actually the heat exchanger. The cars with thermal reactors had no catalytic converters, that was the thermal reactors job. Hope this helps. -WG

H_PersÆng

Yeah that looks about right! Now il only need to figur out whats what :p.

From what i can from the picture it seems like the thermal reactor you are talking about is the same part as the heatshield i was talking about....

What was left of it looked like a heatshield but then working the oposite way, it kind of looked like a doubleplated muffler....that one is totally screwed...but thats not what i welded (there was nothing left to weld really).

But like i sayd i will post pics of what i welded as soon as my damn pccam arrives

Wankelguy

Save the top part of the thermal reactor heatshield when you switch to a header. It makes a dandy heatshield (duh.) as well as providing a lower attachment point for the carb pre-heater hose.

Rex4Life

Might try the ATF trick to get them engine/oil seals lubed up. I think they tend to not work when they lose all their oil from sitting around.

H_PersÆng

Well, wankelguy...first of all thxx for all the help ....

Il see what i can salvage from that thermal reastor thing but if i look at your replys it seems like its toast nomatter....im not planning on paying big for something like that so il prolly be replacing it with a header than....

But wont that create toxic exhaust fumes? (not that i really care but ;p)

So when i install a header i can get rid of the airpump then? Moreso it might not be so evidently to get ris of the airpump because the pump is also used to tighten the pullybelts....so when i get rid of that i will have to find some other way to tighten that belt....unless ofcourse im being an idiot andthat belt is used solly for the airpump....i dunno i should go and have a look :p

About that ATF treatment.....yes i was planning on doing that for sure....il just need to do a search for it, i tryed searching for it but i didnt really find anything...nomatter, il figure it out, thx for the help sofar..

And about that heatshield....all thats left of it is the top one so i was gonna hold on to that one anyway...the rest of it is just a pile of redbrown dust lying in my garage right now

LOL, man, if im gonna have to rebuild this engine im gonna need a wigg couse i think il be pulling my hair out right around that time...hehe. Id have to say that this rotary is totally unlike my celica engine...i used to think the celica was hard to handle but this..lol, anyways, thx for the help :p

H_PersÆng

OKOK, i think i finally got it figured out now.....i took that diagram you posted over to my car and took a look at it....

Well it seems like the heatexchanger is useless! On top of that my entire exhaust system is beyond (any sensible) repair so the thermal reactor has to go two...

I guess il be getting a new exhaust and covering up airpump holes then...

Now that i know this i am in need of a fair dealer that could provide me with these parts....im in belgium...any ideas??