TempestRaces

Hello all,

I have a 1990 RX-7 N/A which has totally lost compression. I was wondering if anyone could give me advice on what to do with the car now. I live in the smallest province in Canada and no one will work on this car, so getting a shop to rebuild it is out. I had one guy lined up but he kept the car 6 weeks, said he had it almost ready, said that the new seal kit was in but the car backfired a lot. Well, that's what it was doing when I took it up to him. Took it to a new garage who said it has no compression because the first guy didn't do anything with it *sigh* Well, I only took it to someone because I wanted it fixed for summer. Well, summer's over so now I have no rush, long as it's done by next summer. I am a first year automotive tech student and my teacher, while rotory impaired is one of the best intructors in this field. He's willing to let me take in to the school shop to do the rebuild on fridays, which are student days to work on our own rides. My question is this, is this something that I can do with the help of my teacher and class, even though we don't know rotories, or should I look to purchase an engine already rebuilt online. My second part of this question is, if I wanted to go to a TII anyway would it be best to just find a TII engine that needs to be rebuilt, rebuild that and just drop it in when done or should I look for a rebuilt already TII. I'm not afraid of the work, I just want to know if it's feasable and obviously there's a call for someone who knows how to do this in my area so i'd kinda like to learn, if others who've been there think it's possible...Sorry for the lenth of this but while I know lots about piston engines the whole rotory thing is kinda throw'n me. How long would it take to do a rebuild on this engine if you worked at it 8 hour days in a well equiped shop? Any incite anyone wants to offer would be super!

SICKRX7

I admire your enthusiasm. Rebuilding a rotary is not all that complicated if you know what your doing but have tghe right tools is a big part of it. Depending on whats wrong with the motor you might be able to rebuild it. but if the rotors need to be machined your gonna have to send them out and that can be costly alone, you also need a rebuild kit. i have never bought one but im told there around $1000.00. so its not going to be a cheap rebuild and most people when doing a rebuild upgrade to the 3mm seals. lets face face it if your gonna spend that much might as well do it all. 3mm seals also require machineing of the rotors. If you do rebuild please keep us posted to let us know how it comes out. I personally am on my 3rd rx and when a motor goes in my car or a friends we usually just look for a used motor or a rebuilt one from a shop or somthing. As for the TII conversion i have already done this on an 86 na. but I had a whole wrecked turbo to work with so it was fairly trouble free. You need to have the motor,computer,tranny, and the na rear will work but its a differant gear ratio than the na's. it took us (me and a friend) about a month to do it but its done and there are no current problems. Let me know if you have any more questions you can email me if you want.

Jodoolin

Phew, long post and I am confused. If you "Totally lost compression" I doubt it would run but you sa it "Backfires a lot" It would not run with zero compression.

Please let us know if it runs, if you have done a compression check, or what it sound like when you try to turn it over. If you have zero compression and it is turning over but will not start it may be as simple as a badly flooded engine.

Better description of symptoms would be real helpful.

TempestRaces

Ok, more info coming up. It ran like hell for a week after I bought it. I bought it because I was told that it only needed to be worked on and a garage was willing to do the work for a reasonable rate and I got the car dirt cheap. The rear rotor needed work was what I was told.

Didn't drive it at all after I bought it but to get it home, then went to drive it to garage that was gonna do the work but changed my mind and had it towed. Before it went up there it would run if you revved it but would only idle sometimes and would idle really rough and backfire. It would also stall out a lot at idle

It went to the garage of hell where it sat for 6 weeks on his lot while he lied to me about the progress of the work, at first a guy was out sick, then he had to order the kit..etc for 6 weeks. Then he said he did the seal kit on it but it still backfired when it was back together.

I went out to get my car back because quite frankly I wasn't waiting any longer and it was backfiring when it went up to him. I had the guys from the garage next door to the garage from hell push it to their shop because I asked around and these guys are good but as is the story around here don't really work on RX-7's. They agreed to see what they could do/find out, they figured it needed new plugs and maybe injectors.

They did a compression test and it aparently doesn't have any. At all. When I went to get it from the first garage after he told me it was running but backfiring, it would click over but would not catch at all, as far as I knew it was running on one rotor when he got it. I don't think it is just flooded. I have been told by the good garage that I need a motor or a rebuild. So I just wanted to know if it's possible to do it yourself and what to look for/if I should go to a tII now if I can get my paws on one. I'm pretty sure the current engine is FUBAR and will either need a rebuild or a replacement.

Again any adivce would be super, and thanks for the info on the 3mm seals. I apreciate it greatly, if I rebuild I will look into that. Oh and due to my course I get all parts at cost, same as the price a garage would pay so that may help

5 point whoa

little tip, rx7s backfire like crazy all the time, does it have any exhaust work at all done?? if it does, then backfiring shouldnt be a problem at all, but if theres low compression, I'd just say get it rebuilt, or look for an engine in the parts for sale/ wanted on the forum.

Jodoolin

Ok, let me see if I understand. A compression test was done by a mechanic who claims there is absolutely no compression in both rotors? If so, the engine is not in need of a re-build. It is very badly flooded. If injectors are leaky you have been seeping gas for the 6 weeks it sat unused. The gas has washed out the oil film that helps maintain seal integrity.

Save yourself a ton of grief, money, and being taken by mechanics who do not know RX7s. Do a search on flooding, compression, ATF trick, and unflooding. Use the "SEARCH" button at the upper left top of the page and be willing to take the time to learn a bunch. Unflooding is relatively easy but may be a bit more difficult if you have zippo compression. It can be done... be patient. This is one of the times I can speak from experience. I also totally lost all compression and restored with the ATF trick but I used MMO.

All this will do is get her running. If you have a weak rotor that becomes another issue you will have to address some time.

5 point whoa

nicely said, thats exactly what you should do

TempestRaces

Thanks guys! so no compression at all means badley flooded eh? Good to know. I'll see what I can find out about that and just have the car towed to my school anyways. Then if it is something worse then it's already there and if the fixes for the flooding get it working then I'm all set. That's great to know. Anyone have any fav sites about tech issues on RX-7's they'd care to share? And if it has a weak rotor is that a rebuild issue?

Jodoolin

A follow-up with stuff that may be helpful. 1. Read the Sticky at the top on "FAQ for FC". It has a lot of info that you, as a new 2nd Gen owner, will find very useful. 2. Within that sticky will be links to Factory Service Manuals. If I were you I would download the one for the "89 + or go through the trouble of printing each section. You will use it a bunch as you work on your car or 3. Get a Haynes Manual for the RX7. 4. Only bring your car to school to be worked on if and only if you have either the FSM or Haynes. Piston mechanics, as you have found out the hard way, know diddle about rotaries as a general rule even if they are auto mechanic instructors.

This is what I did to unflood my '90 NA that was badly flooded. A bit unconventional method but it worked. Symptom? When I tried to turn it over all it did was whine. The rotors sounded as tho they were freely spinning. When I remove the trailing plugs from each rotor there was absolutely no pressure puffs. Flooded!

1. Removed the EGI fuse from the fuse cluster in the engine bay. 2. Removed all 4 spark plugs 3. Turned it over, with the pedal to the floor, in 10-15 second increments about 1/2 dozen times. (the attempt here was to blow as much liquid and vapor out as possible) 4. Poured in about 2-3 oz of MMO into the leading (lower) plugs and put spark plugs back. 5. Repeated #4 for the trailing (upper) plugs. 6. Let it sit 3 days. 7. With the EGI fuse still out, removed all 4 plugs. Repeated #3. 8. Replaced spark plugs which had been dried and cleaned up. 9. Replaced EGI fuse. 10. Attempted to start with pedal held to the floor (do not pump). 11. Did not start but wanted to. 12. Removed EGI fuse only and went thu the unflood process. 13. Replaced EGI fuse. 14. Started on the third attempt and has not flooded since. Phew!! Was frustrated and miffed it took so long.. so be patient.

Good luck.. Jerry

TempestRaces

Jerry,

Wow, thanks so much! I'll get those books, Hayse and see what I can find online plus the owners manuals.

We also have the program called Mitchell on Demand that has all the instructions for jobs, with diagrams and everything that should be helpful too. So many piston mechanics mean well but just don't get it. And as I fall into that catagory myself I really want to learn all I can about this car.

The unflooding process is as long as that huh? Well, it's worth a shot at least. I really can't thank you enough for all the great info, I'm going to start reading. Again, thanks bunches to all that took the time to answer.