no compression...
 

I have an '89 non-turbo that won't start... got a good compression gauge, tested today and got NO compression on either rotor. I looked in the plug holes with a flashlight and mirror--- and see nice shiny apex seals... for what it's worth...

the guyI got it from had poured 90 weight gear oil in the spark plug holes before I got it. I put 2 oz. marvel mystery oil in each rotor, cranked and let it sit a few days- My friend towed me around the neighborhood, which turned a nice shade of blue from smoke as high as trees.

It still didn't even think of running- so I then added 2 oz. of WD-40 per rotor, cranked, let it sit.

there's more to the story, but thought this is a good start...

ok... original owner had it 15 years, as his WINTER car! drove a mile to and from work every day. One day in February, after driving 8 miles, it lost power, he pulled over and assumed the engine was shot 'cause it lost compression. Doesn't seem as if he 'beat' it... it just lost power and stopped. does that sound normal? it has 63,000 miles...

and... the air temp sensor on the air intake had a broken lead- I fixed it, tested it and hoped it'd run....

so- does any of this sound familiar??

thanks...)

maybe it overheated...... and coolant seals are gone and it rusted the apex seal so they arent spring no more and then when u crank it, it scratched off the rust on the surface so its shinny???

just cause the apex seals are shiny doesnt mean its getting any compression my seals were shiny but when i stuck my camera in the exhaust this is what i found

http://photos.yafro.com/pics3/i/2004...2f540_full.jpg

well... there's no sign of coolant in the chambers- no oil in the coolant- and no coolant in the oil... does that mean the coolant seals are ok?
and- it was february, winter in Pennsylvania when it first lost power and stopped running... so doesn't seem as if it'd have overheated...

I didn't see any signs of rust there though- but you can't see much through aspark plug hole...!

what about corner seals...?

[QUOTE=capn]just cause the apex seals are shiny doesnt mean its getting any compression my seals were shiny but when i stuck my camera in the exhaust this is what i found

QUOTE]

WHOA! that's cool! but- what's it look like to you? scratches in the housing plating? were they deep enough to reduce compression to zero?

[QUOTE=Buffalo Bill] I think you're missing the point. Look at all the rust.

If your apex seals are stuck you'll have no compression.

Yeah, I've been hoping that the seals had stopped sealing because of rust... and that they'd pop out again when it got running- I had a 1st generation about ten years ago like that... had it running in half an hour- not as lucky with this one...

still seems like there might be a gizmo not working right that made it stop the first time----

it looks to me like there's been 'bluing'... from heat, and two score lines of scraping... or are they raised? the walls there should be perfectly smoothe and shiny, right?

do you think that after gear oil, mystery oil and wd-40 over a month in there, they'd loosen up?? maybe we should try towing again...??

th

hey, when you pull the exhaust, can you get in there and work the apex seals in and out with your fingers or tool or something? or is it too hard to reach? the exhaust has been disconnected at the front pipe... it can come off again easy -

slpin, what'd you say?

capn, did you ever get it running again? or rebuild? what happened?

josh, did you ever get apex seals loosened up?

interesting, i dont remmeber me saying anything
or if i did, i definately forgot....

use lots of ATF, and soak/drown, whatever ur enigne in there for a bit... they are really good to break stuff loose, better than wd40

if that doesnt work, o well, u wasted 4 bucks for a bottle and ur engine.... its lost hope

yep, ATF's what they all say to use- but i have heard of people using marvel mystery oil... and my cousin has his own racing engine oil additive- and said he's used wd-40 to loosen up a tractor engine...but...you're right, it's worth 4 bucks to give it another shot!!

heck no that front rotor housing was rusted, the apex seals and side seals were all rusted in and very hard to get out. plus both chambers suffered apex seal breakage and coolant seal failure. so the motor was no good as it was.

did you pull that engine and open it up? that's how you knew the seals were hard to get out? so what'd you do, rebuild it?

that engine was basically scrapped. no rebuilding whatsoever. i donated the parts to my old highschool for a demonstration. other then that it was worthless because the housing were all torn up and the irons had heat damage. so there was no saving it. but im in the process of building one for fun now

ah, i didn't see the next post you made...!
so, are you going to build another wankel and put it in that same rx7?

hey, what're the corner seals made of? it still seems odd to me that this car died in midwinter, while being driven, like normal... can't imagine all the seals going at once, can you?

no, that first RX7 is long gone, im just building one for fun and sellingit to whomever wants it. or i could dropit in a beetle my friend has.

the corner seals are steel with rubber inserts. so the engine was running when it died?

hmmm... i might need one- for an 89 non-turbo, right?
does it bolt up to a beetle?
so, are the rubber parts exposed to the heat and pressure? wow-- it seems they'd be likely to be destroyed if there was an overall failure, like oil injection, overheting- right? or is it the steel part in contact with the chamber walls?
that's what the original owner said... he had it for 15 years- drove it as his winter car in Erie, PA- drove short trips to work, like a mile each way... was driving for about 8 miles and it started to lose power- said it 'started losing compression'...which, of course, how would anyone know that for sure....? more likely to me it had a fuel or ignition or other device problem... it's been sitting now for 7 months...
the mechanic i bought it from had put gear oil in the spark plug holes- thinking it's thicker and would help compression...... then, i put marvel mystery oil, then later wd-40... just now, i put about 8 oz. of ATF in each chamber. how long should I wait? (forever?)

well the most definative way to check it is to get a compression tester, if you assume that its a good motor you are going to spend money on other things thats not the problem and end up hating yourself because of that assumption. now there may be a very small possibility that they (the apex seals) are stuck. i left ATF in my engine overnight, and now knowing the engine was no good it was useless. But try squirting some in leave it overnight turn it over for 10 second intervals 3-5 times (with EGI fuse out). and CHECK COMPRESSION with a tester. if that tester reads below 80 ish motors gone.

and the little rubber pieces are subjected to heat and oil and such and just end up getting hardend and sometimes even desintagrating (sp?)

and the motor im building right now is going to be using S4 turbo rotors, its gonna be some experimental stuff in it. and they have tranny adapters for many different engines.

Buffalo- My engine from time to time will loose compression if I start is and quickly shut it off... if I am moving it out of the driveway to get another car out or something... I have ALWAYS used ATF to make the seals come back. The ATF makes the seals swell more than WD or Marvel- Just full them full of ATF and then spin the engine over on the starter... You should begin to hear compression...Then put the plugs back in and see if she will start... If the engine starts on one rotor... Make it run to get it up to temp...then shut it down and then work on the other rotor. A little bit of temperature in the engine works wounders... You just have to be patient. ONLY USE ATF... I have never had any luck using anything else. Good luck! Keep us posted!

You apparently have never had an engine apart. Unless you actually believe that ATF can cause metal compunds to swell. The only seal any where near the combustion chamber, aside from the rubber corner seal plugs, that can swell, are the rubber oil control rings. If those have shrunk, the engine usually needs rebuilt and is smoking badly.

Raw gas from flooding removes the oil film from the inside of the housings and rotors. This does 2 main things. It removes that boundry layer of lubrication that aids in sealing the combustion gases and allows the seals to stick in thier grooves, due to carbon build up. ATF does not swell anything, it replaces the lost lubrication and can allow stuck seals to begin moving again.