I am new to the forum but not new to my '89 RX7 GTU non-turbo as I bought it 14 years ago when it only had 27K and now has 108K. I'm a shade tree mechanic but have kept it well-maintained through the years with few problems. Now I'm at a loss and my primary question is does anyone know a rotary mechanic in Reno, NV?

If not, here's the issue: I started it three weeks ago and moved it about three feet to get it away from a car that had practically parked on my bumper. Next day, I went to start it and it turned but showed no signs of firing, just whirring.

Starter is new, ignition switch, plugs, wires also, it's getting spark and pressurized fuel, checked resistance of coils and crank angle sensor, all with correct values. Finally I checked compression and had absolutely none. I've been reading the FAQ section here and scouring my Haynes. Downloaded a factory service manual but my brain is swamped and I fear this is out of my league. Seems to keep leading back to these Apex seals, but I'm wondering if it could also have to do with the regular oil pump or metering pump. I'm not sure how to distinguish exactly what it is. But with the car still in such great shape, I hate to toss up my hands and try to sell my baby for parts. It just doesn't warrant it with so few miles and body in near perfect shape.

I did check a plug and there was some light oil covering. Would this tell me that it is definitely seals? I know a licensed Subaru mechanic who has shown the willingness to do the work despite the fact he's never opened a rotary motor. But he's requested that I do my best to isolate the problem as specifically as I can so that he can study the manuals and do the repair research. Though I sure wish I could find a rotary person in Reno. I've called two dozen so far with no luck.

I apologize if this is covered in a thread that I haven't found yet. Thanks for any help finding a mechanic or answering the mystery.

 

rather common on engines that sit for periods of time and have a bit of carbon buildup. basically your apex seals stuck in the rotors and aren't sealing.

pick up an oil squirt can from a tool store and a bottle of marvel mystery oil from your auto parts store. remove the 2 vacuum caps on the lower intake manifold ports, get a short piece of vacuum line and shoot about 5 pumps of MMO into each port. crank the engine for 5 seconds and let it sit for 15 minutes. pump 5 more shots into each port and cap them back off, now try to start the car, rinse and repeat until the battery dies or the engine starts.

beware, if it starts it will smoke like a train for about 5 minutes, longer if more MMO is pumped in.

if you are lucky and get it running, do a search for "water treatment" or "decarb treatment" and follow the procedures. if it recurs then the engine is producing too much carbon and likely just needs to be torn down and rebuilt.

worst case, bring the motor down here.

 

Thanks so much for the help. I'll try this next once I locate the vacuum caps. Usually takes me a while with new stuff, but I'm tenacious, and I have a bunch of manuals. Even if it starts, though, I may bring down to sin city and do a rebuild so I know she'll keep going and going and going. If it doesn't start, I'll have to look into shipping it down to you from Reno. From what I've read, it's worth getting it to someone like you. Marc

 

good luck and if you have any questions feel free to PM me.

 

Thanks for the offer, Rotary Evolution. But apparently I can't send a PM as this is only my third post on the forum. Unfortunately, though, I do have a quick question. Forgive my ignorance, but I see three hoses coming out of the intake manifold, but not sure where these caps must be. I'm assuming I'm looking for just the little black caps that pull off, not something else. When I'm looking in at the intake manifold from passenger side should I be seeing them? Or am I completely off base? Any direction is greatly appreciated by my addled brain. Marc

 

up at the right front strut tower in the engine bay front side is a small black box with a vacuum line attached to it, follow that hose to the engine and you will see multiple connections on the passenger side of the engine, just above where it attaches you should see 2 metal lines coming up and facing out kind of buried under the BAC idle solenoid, they will have vacuum caps on them and are auxiliary ports that i use for checking individual rotor vacuum, doing water treatments and inject oil oil into to build compression with.

 

Or you could just remove the top two (trailing) plugs and squirt a little ATF in there. Put the plugs back in and see if you can build the compression back up. This worked for me before.

 

I have an 85 GSL-SE. Mine used to do the same thing when I'd start it and shut it down without warming the engine up. Tended to do this more frequently after the car had some miles on it. I'd bet you have plenty of life in the engine, though, just be careful to avoid the short starts. Take a look at this, it may be a little helpful:

Rotary Performance - Tech - 84-85 GSL-SE Unflood Procedures

 

Thanks for the tip. Never would have thought to use ATF to squirt in there. I'm assuming you are referring to Automatic transmission fluid.

 

Thanks for the help. I did try just holding the pedal to the floor but had not used the procedure with the coils. I'll give it a try.

 

Yes. ATF is automatic transmission fluid. Dont squirt a whole bunch just a little. It isn't going to harm the motor but it will smoke like crazy for a bit when you get it started. You referenced a plug that you pulled being oily. A flooded rx7 plug will be oily like that. I suspect the short start and then moving it only three feet and shutting it off flooded it. Very common for rx7s. Your engine is most likely okay and your apex seals are probably just fine. here is what I would do.

1) get a new set of spark plugs. there are leading (lower) and trailing (top) plugs. You can get them at O'reily's usually or if you can order them online from rockauto.com.

2) take out the old soiled plugs. Keep track of which plug wire goes to which plug.

3) before you reinstall the plugs, pull the egi (injector fuse) from the fuse block under the hood. It's marked EGI.

4) once that is pulled, with the plugs out, crank the engine over for a good five count. wait a few counts and crank it over again for a five count. This will expel whatever is flooding the rotors. gas and oil usually.

5) put the egi fuse back in.

6) install the new plugs and re-attach the wires. don't mess them up.

7) get back in the car and crank it up. Don't touch the gas pedal. It may start right away, or it may not. with fresh plugs and gas blown out of the rotors it should be good to go. Be patient. I had an 88 that would do this occasionally and I always got it running.

good luck.

 

Marvel Mystery oil will deff. do the job used it on every seized engine ive had and fires it right up even engines that are seized for years and have been in the rain...Good luck hope you have the rotors turning again but deff. good advice you have gotten and especialy about changing the plugs you have to be careful with the 88 flooding too i have had to wire the fuel pump to a switch on several of them for some reason they like to flood themselves.

 

Thanks so much for all the valuable assistance. And for being so kind to a newbie. I'll be diving back into the problem this weekend once I'm off work with renewed hope and hoping for some good luck from the RX7 gods. It's my only rig and it's been so reliable for so many years it's odd having her sit. But hey I'm getting lots of exercise walking everywhere.

 

i prefer marvel mystery oil because it is less harsh on the internal seals where ATF will cause them to swell, it also doesn't smoke as much or for as long as ATF will. aside from that it does the same job of aiding in compression due to stuck seals and freeing them up.

i have also used it on siezed rotaries with good success, one was a rotary pickup that hadn't been run in over 25 years and the engine was siezed up. worked it loose and it ran perfect.

carbon buildup does dry out over time so any engine that has excessive carbon buildup can stick the seals in either the out or in position which results in a siezed motor or one that spins totally free but builds no compression. without compression the engine can't combust the air/fuel to get it running.

pull starting is also an option but one i have never had to attempt.

 

A day after my last post, my elderly mother was in need of assistance and I was called to the East Coast to care for her over the past four months. I returned on Thursday and today utilized all of the valuable suggestions to get the car up and running again.

After following the procedures put forth in this forum, the car started on the first attempt. About forty seconds of 'train' smoke blew out, then it purred. I immediately added "Sea Foam" additive to the gas in hopes of cleaning out the carbon (this product was recommended by a guy at AutoZone. If anyone has any other suggestions, please pass them on). Then I let it run for three hours.

Before I shut it down, I held the accelerator down for a couple of minutes and halfway through came an extended blast of blue, then, black, then gray smoke. Finally no smoke and I let it return to normal idle. I'm hoping that was cleaning out some of the gunk. If it starts again tomorrow, I'll take it on the highway and see how it runs.

I thank everyone for helping me out with this problem. Not sure if I'll still need a rebuild, but, if so, I'll have to save up some cash after the recent outlay with my beloved mom. RX7club rocks.

Thanks again. Marc

 

Just regular old carb cleaner (make sure it is safe for rubber) sprayed into the spark plug holes (get each side of the rotors by rotating the engine between sprays) will dissolve carbon. Then put about ounce of oil into each chamber and rotate the engine to flush out the carbon.

"Sea Foam" and other in tank additives are going to have very little, if any, effect. They are just snake oil.

Now that the car is running, some long driving on the highway, gradually increasing the load on the engine (higher RPM and throttle) over a period of a few days will do wonders to clean things out. No need really for any tricks and such.