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Bent-Valve Reader
9/9/18 10:09 p.m.

The good engine is from an automatic, as accordianfolder said, "RUH ROH".

After some research I find that since it is a 6 port it will fit. Now I need to get this off the old engine.

I read some people have trouble removing either part from the e-shaft. I notice the bolt holes lined up with the ridge on the main seal ring. I threaded the bolts through and added even pressure, a few blows from a small hammer and both the flex plate adapter and the flywheel popped loose.

It did take a 54 mm socket and this is where Pyro needs to be nominated as a Saint. I was using my very old 1/2" breaker bar and it got the first one loose, it failed on the flywheel. The 5 foot cheater pipe may have had something to do with it. I think one piece that flew past my head may be in orbit still. The pieces I found are in the bag.

So I was going to get a new 3/4 inch impact ($99) and Pyro decided to get me a pretty good HF 20v max 1/2" impact. It took the nut off in less than a couple of seconds. Advertised as 1200 ft lbs of torque, I hope it holds up I like it.

I had to use oil pan off the blown motor, so I had to clean the metal flakes out. This is with the baffles out:

And ready to seal up:

Cleaned up and baffles back in:

In the morning I plan to finish transferring the intake, electrical and exhaust stuff.



Bent-Valve Reader
9/10/18 8:09 p.m.

Totals for car right now

$2000 for the car and spare engine

While it's not a $2018 Challenge car I am building it in that spirit. So today I have to order my first parts. I found a good intake gasket and reused the exhaust gasket which was in good shape. The pan is sealed with RTV I had in the shop. I bought another tube just in case but didn't need it. The parts I have to order are the pilot bearing gasket, and a pilot bearing. I slipped getting the seal out and tore it.

But when that comes in, the "good" engine is ready to go back in.

The part I thought would be difficult was the oil injection pump. It turns out its a sensor and was a simple remove and replace. it slips over a stub kind of like a CAS on a Miata, just 2 bolts. The old one was smashed, who ever removed this engine was a little rough, sawed cables, hole in oil pan, intake vacuum tubes were mashed  and a smashed oil pump sensor. So I had to remove everything off the blown engine short block and put it on this one.

Finally I cleaned out the oil cooling system to flush metal flakes from the bearing. I used this old air compressor to blow the cleaning fluid through. It may fit the GRM spirit. A guy gave me 3 blown up air compressors (free) and this is made of the compressor from one, the motor from another and the tank from the 3rd one. I built it over 16 years ago and it is still running.

And Ziggy tortures and kills anything that moves, I feel sorry for the mice. Not. smiley


Bent-Valve Reader
9/16/18 10:12 a.m.

I made a new clutch pilot bearing shaft to handle the extra seal. It has 3 steps. The second one is .020 smaller than the seal. I'm just posting pictures of the tool for now, at 11:30 last night when I had gotten the engine in place but not bolted down I didn't feel like taking pictures, beside it's just an engine in  the bay.



Brett_Murphy GRM+ Memberand PowerDork
9/16/18 12:27 p.m.

On the RX-8, it looks I think the rear counterweights are the same for all engines, but the front is different between the manual and the automatic. While you've got everything out, it may be worthwhile to confirm this, especially since you'd have the correct manual one from the blown engine available.

Bent-Valve Reader
9/16/18 9:20 p.m.

 That odd shaped counter weight with the 6 bolts is what the flexplate on the automatic bolts to. The round part just slips off and under that is the 54 mm nut.

On the flywheel there are thick places cast in and they serve as the counter weights. Sorry I didn't get pictures of the back of the flywheel.

Either one fits on the eccentric shaft (don't say crankshaft I found out...) using sealant, a key and that crazy big nut. I took the shot below to show the seal, but it shows the automatic counterweight on the toasted manual engine. I was trying to get the pilot bearing out. The grey goop is the sealant.


This is all relevant to the 6 six port high output motors, I have no clue on the early 4 port motors.

The only thing on the front of the motor is is the main pulley mount with a toothed wheel for ignition timing. I can't find any difference in the pulleys but did use the one from from the original motor. When you asked I realized it doesn't have a harmonic balancer, I guess because there are no pistons stopping and accelerating the other direction.

Now to add to my worry there are different numbers for manual and automatic e-shafts, but from what I can find out that is for the four port motor. So if it vibrates when I fire it up I guess I get to start over....

Tonight I got it snugged down on the mounts and 2 of the transmission bolts in. I'll get the others in tomorrow if I have time. I am on the down hill part of getting the "good" motor in.

edit -- posted 2 pics for some reason, removed one

wvumtnbkr GRM+ Memberand UltraDork
9/17/18 7:12 a.m.

Does the rx8 have the issue of the Torrington bearings "falling" when you remove the front pulley without pressing on the flywheel?

Mr. Lee
Mr. Lee GRM+ Memberand UberDork
9/17/18 2:13 p.m.

It's been a long time since I've snorted the magic dorito dust, but IIRC 50k was nothing for a NA rotary. more like 200k then you started thinking about a reseal. The street port/stock port turbo motors would go ~90k between rebuilds if it wasn't abused. 

Brett_Murphy GRM+ Memberand PowerDork
9/19/18 8:23 p.m.

The front counterweight is under the front cover, number 11 in the diagram below.

fidelity101 UltraDork
9/21/18 8:10 a.m.
Brett_Murphy said:

Getting the engine out of the top is possible. It's just not easy until you do it the first time and learn the arcane tilts and wiggles you're going to have to use, and it has to come out at a steep angle. Unbolt it from the transmission for sure.

you mean the 350 shake? no problem!


@bent-Valve - why unicorn rx8 though? I see a sunroof. 

easy way would be to pull the engine alone, get yourself a series of LONG extensions and you can get at every bell housing bolt from the tailshaft end of the trans pretty easily. 


keep up the good work!

Bent-Valve Reader
9/23/18 8:30 a.m.

just drop it in...


Well I did, but now I am regretting that a wee bit.

This is what it looks like and has since last week before the front counter balance was mentioned. I started trying to get the front covers off, that means the e-shaft bolt needs to come off first.

A brand new impact that spun a 54 mm nut like it was a twist tie won't even budge it, the socket started to get warm from the hammering. I put so much torque on the one in the car I started to worry about damaging something as the parking brakes gave in and the car started to move.

I am researching front counterweights, they are different. One thread I found on another forum said its not a problem unless you run lots of high rpm.

So here is the experiment:

1) Control -- Finish install with auto counterweight, note vibration.

2) Variable -- Rebuild manual engine, install, note vibration.

I am not sure I can get this engine apart to replace the front counterweight without pulling it. Even locking the flywheel requires it separated from the transmission.

Brett_Murphy GRM+ Memberand UltimaDork
9/23/18 1:06 p.m.
Bent-Valve said:

I am researching front counterweights, they are different. One thread I found on another forum said its not a problem unless you run lots of high rpm.


High RPMs are kind of the point. It may be fine for street driving for a while. I mean, it was a used engine in the first place, right? I wouldn't run LeMons or Chump in it. 

(oh, wow, this was my 7500 Post, glad it was trying to be helpful and not in the hotlink thread)

Bent-Valve Reader
9/23/18 7:43 p.m.


I think I found what killed the last engine, Renesis are oil cooled as well as water cooled. This is the oil cooler and the other one looks the same. I think the PO just washed it with a pressure washer and mashed the fins flat.

And I got the radiator in, here I am using double sided tape to reattach the foam. There are seriously 2 billion screws that hold this bottom tray in, it is nicely designed to control air though....

Now here is where "Smoky" earns his name....


Wait for it....




Wait for it....









I oiled the short block before I spun it so this is not bad or unexpected. I could only run it for a few seconds though, there is no antifreeze in it. I have misplace the hose that comes off the MAS and have to figure that out in the morning. Oil pressure came up and it died once or twice until the air was out of the injectors then it was smooth.


Indy-Guy UltraDork
9/23/18 8:46 p.m.


yes wink

Bent-Valve Reader
9/23/18 10:33 p.m.

Couldn't leave it until morning, it was not the MAS but the throttle body, and the hose was hidden under it. So with all put back together I strained the antifreeze through a coffee filter (Pyro's idea), filled it up and ran it for a few minutes.

CEL is on, and TPS warnings, I will sort that out in the morning, no really I'll wait until morning this time. cheeky

We put the hood on and I took it for a real short drive.

Transmission or throw out bearing is whining, I'll have to check the fluid level. Engine is smooth even on really old gas.


Bent-Valve Reader
9/30/18 9:52 p.m.

Long story short -- runs, but not right.

It has a CEL and its for the SSV, which it thinks is stuck. I can move it freely, so maybe the its the switch that reports its closed. I may look at it in the morning. I have the switch off the original motor.

It is also in limp mode, without a code or light. This is due to the sensor I replaced on the oil metering pump (omp). Its misadjusted or the omp ( a stepping motor controlled valve) is bad. I have the one that was on the original engine and if I get to it tomorrow I will put that on also.

I put in the shop and got things arranged but don't feel like messing with it tonight. I was rereading DB13's thread and he is right, when its not fun, stop. It supposed to be fun.

You will consider me as mental but since it runs I wondered about pulling it out, yes, I know, and use both engines to build a really good engine this winter adding any needed parts. I would pull the transmission also and find the source of the whine. I could put the correct counter weight in since there is a slight vibration at 4k which is as far as it will wind up in limp mode.


Bent-Valve Reader
10/7/18 2:25 p.m.

so at 6000 rpm the junkyard engine starts to wake up...

I guess I should start from the beginning...

I was working on get rid of dash lights, I keep getting the limp  mode related to the omp (oil metering pump). I had clocked the sensor wrong. So here is how to put it on right. The omp sensor is a throttle position sensor and is spring loaded. It has a slot that fits over the stub shaft.

Put it on with a counterclockwise twist like so.

Now if you twist it clockwise the spring will load up and twist it back if you let go. (and yes this is the broken sensor I am demoing with)

And this fix killed the limp mode problem and the engine will run up past 4k.

So then I checked the code P2070, it says the SSV is stuck, well its not, at least not enough to feel. I worked it back and forth easy, it moves very freely. So it might be the switch that tells the computer its closed.

Then I had an oil light all of a sudden...


I had just put 5 quarts in plus a new filter. So I added another quart. Turns out if you change the oil it is only about 5 quarts, but I still had the oil light. What I did different was flush the oil cooling system. Turns out the entire system is 7 liters (7.4 quarts). Also the mark from low to full on the dipstick is almost 2 quarts.

Now the oil light is out, But the DSC and yellow skid lights are on. If you disconnect the battery you have to reset the DSC system. Its pretty easy once you know how, I jacked the front tires up to make it easier... Note the lights

Turn the ignition on, turn full lock, I went left but don't know if it matters, then full lock right and back to center, turn the key off then back on

Ta-Da! gone!

So most of this happened last weekend and I got insurance, inspected and plates. On a chip seal road I tested the engine and about 6000 rpm it gets happy. I have no idea what the compression is on this engine but I did my best to clean out the carbon which should improve it.

I Seafoamed it twice... There is Marvel Mystery oil and 2 cycle oil in the gas to help protect the seals. And new premium gas mixed in with the old gas. I have run it up to redline several times and it hasn't popped yet so I guess I am now a rotary owner!

Matt drove it today and agrees for a $2147 car its not to bad at all.

Edit -- Tonight Pyro and I went for ice cream. Sitting in a parking lot we switched after we ate and she drove around the parking lot getting to 3rd around some light poles, and it ain't that big of a parking lot....

She didn't hammer it as hard as I have but she did stand on it pretty good going home. So if you ever read the thread "Should I sell a running car to buy a broken one?", the answer is definitely yes...

BirgerBuilder Reader
10/8/18 2:23 p.m.

Nice work! A high quality budget build. 

Stampie GRM+ Memberand UberDork
10/8/18 3:22 p.m.

You could sell the bad engine and get under $2018. Just saying ... three days.

Bent-Valve Reader
10/8/18 3:28 p.m.

The quality of the build just got better...

Seriously, since it has been sitting for 2 years it has 4 recalls and an appointment Monday. I don't want the airbags trying to kill me. Also the lower ball joint and fuel line recalls seem to be important for some reason.


Bent-Valve Reader
10/8/18 5:39 p.m.
Stampie said:

You could sell the bad engine and get under $2018. Just saying ... three days.

I had thought about that. FMV for a blown 13B? Even at picknpull price it gets me under. However I just started with my present company 5 weeks ago so I have NO vacation built up. I suggested the accordianfolder drive over grab it and head south, I not sure he thought I was serious.

Bent-Valve Reader
10/15/18 8:41 p.m.

Well I broke it.

In my defense I was having fun, I turned the DSC off and a redline warning beep (or two or three ...) later the alternator start screaming it wasn't happy with this turn of events.

We considered renaming it Squeaky. People stared and commented. About the time I got home it quieted down some.

The bad part is nobody in town has an alternator and I was taking it to Eddy's Mazda to get the recalls done this afternoon.

May be unrelated but it stopped idling on the way to the dealer, now it just dies when it drops to 1000 rpm. They are going to diagnose it while they do the 4 recalls.

Ya'll want to start a pool on the repair estimate?

Brett_Murphy GRM+ Memberand UltimaDork
10/15/18 9:27 p.m.

Redline is good for the engine.

Do you have emissions testing where you are? "Google RX-8 pre-mix" and form your own opinions. 


Bent-Valve Reader
11/12/18 4:22 p.m.

Disassemble --

The first order of business was to get that dang bolt out of the eccentric shaft. Leverage is your best friend and I went a little overboard. Lifted with the engine hoist, a long piece of metal bolted to the e-shaft and a 6 foot pipe on a cheap ratchet. Oh and a strap from the engine to the leg of the hoist.

I applied torque....

You can see the green strap to the left. So what do you think happened?

Nope, the ratchet didn't shatter, the bolt gave! I will say that ratchet seems a little rougher now.

Now I am no rotary expert but I am fairly certain a bearing shouldn't look like this!

And that the front gear shouldn't look like this, that bearing is supposed to be in there attached to the other half of the bearing...

There is surprisingly little damage to the front iron but it does need replaced. The center and rear irons might be usable.

Oh and the e-shaft is hosed.

The metal is discolored from heat and it got into the retaining plate on the front gear.

But I have a pile of 13B parts!

Thanks to following Knurled's threads I definitely want to port it as I rebuild it. Thanks Knurled, thanks a lot. wink

Oh and the oil pump is hosed too.

I haven't looked at the rotors yet, the rear should not be hurt, I am unsure of the front one. Well I will figure that out next week.

Bent-Valve Reader
3/4/19 7:17 p.m.

I have read about a method used to revive rotaries* that have lost compression. It involves using ATF to soak into and dissolve the carbon deposits. I watched a YouTube thread where a person tried it, didn't work, however I am not sure they left it long enough and it was cold out.

What does cold have to do with it? A chemical reactions speed is dependent on temp. For like every 18 degrees rise it doubles or something close, I don't remember exactly, high school chemistry was back in 198..... uh a while back. blush

I also read that other things work, Simple green, I have seen the action of Mopar Combustion Chamber Cleaner. I also had a can of  cheap engine degreaser.

I cleaned the rotors from my blown motor with a brass wire wheel and wound up with some carbon flakes to test. I put them in small cups and added a little of each cleaner.


I am going to leave them overnight and then for five more days and observe. I will say as soon as I put the Mopar CCC in it dissolved the carbon, but then its very acidic and I have heard it can etch engine parts if you leave it to long.

This is seconds after putting the fluids in. I'll post another picture in the morning.


*Smoky is running fine except a vacuum leak.   There is a nice looking 2008 in CL with a "bad" engine, so tempting... And its only $1000. I want to try this "cure" for a bad engine.

Brett_Murphy GRM+ Memberand UltimaDork
3/4/19 7:59 p.m.

The ATF is good for using on flooded engines, as it will somehow let the engine build compression enough to push the gasoline out. Or something, I never really knew how it would work. 

That reminds me. In the long ago, you could get apex seals stuck through carbon deposits. That Mopar stuff is pretty neat. The only thing I'd be concerned with is stripping away the film of oil on things that need a film of oil. It looks like you use that, get some ATF in the spark plugs, hand turn it and go from there.

Everytime your thread pops up, I remind myself I don't want or need another RX-8.

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