Apologies ahead of time fot this long post. There is a wealth of knowledge here so here it goes.

I just bought a '90 N/A RX7 in California. My background, I was a mechanic for the Army, so I am mechanically inclined. I'm in between the South Bay and Monterey in California. Long time member but have been inactive since I blew my first FC back in 2005.

I plan to do a rebuild if the problems I have can't be solve via basic maintenance. There is about 174xxx miles on it.

I just want to confirm I'm on the track in thinking through my problems.

I have torn apart 2 13B's in the past, buthave never attempted to rebuild one. I know I'm getting the gasket set and apex seals at least for the rebuild.

First, my temp gauge does NOT go past normal operating temp (stays in middle). Add Coolant light comes on, then goes away. It comes back on intermittently .Coolant sensor was spliced, so I recit.nected it. I noticed the overflow reservoir tank gets full after a day of driving doing errands. I've just flushed tje radiator, and notice rust in the upper tube.
I replaced the thermostat that opens at 180 degrees Fahrenheit. The radiator is an unknown aluminium aftermarket with no bleedplug like OEM. coolant tends to disappear, or go out the reservoir tank. Thinking coolant seal is about to go.

I can't go past 4-5k RPM or crazy smoke, mostly white, comes out. No liquid of any sort comes out of exhaust. Normal driving, there is little to no smoke what so ever. My friends tell me I'm running rich, but they don't know a lot how a rotary functions aside from triangles for rotors.

When I fill up gas, I start up and it smokes white at idle until I get on accelerator and take off. I plan to replace fuel filter and check the system.

Previous owner had a straight pipe om the exhaust. I was thinking og gettimg unversal catalytic converters to put back on, or MagnaFlow directfit converters. Just don't know whichnwould be best to help pass smog, as it has been labeled as gross polluter.

I also replaced the sparkplugs. After doing all that, of need be prior to going to a ref I will probably rebuild it. But if the problems I've mentioned can ne solved with what I'm thinking, I may not to. Opinions on that?

I plan to make it to a meet coming up to talk with other rotary enthusiasts about this and find out what more I can do.

 

I'd compression test the engine.
I think you are on the right track that it may need to be rebuilt.(my .02 though.)

 

welcome.

well i tend to agree with your suspicion (and by the way, by the time it becomes symptomatic, it's not about to go. it's gone - just how far is the only question). it sounds like you may have compromised coolant seal(s). if you're inclined to investigate, then I suppose you could have the antifreeze checked for traces of combustion gases (I don't know where it's done or how much it costs) or maybe pull the exhaust manifold off and turn the engine by hand and see if antifreeze is in the combustion chamber(s).

for your emissions issues ... you may want to browse the regional forum that includes Cali, as there's probably advice on building a system that can still pass emissions there, if you're not inclined to run a fully stock system.

 

I may have figured out the coolant problem. As I've mentioned (or tried to using my phone), Add Coolant keeps coming up intermittently, even tho' my temp gauge stays at normal op. After looking through for a radiator, I went to Mazdatrix and read their nice Note at the bottom for radiators. That's exactly what's going on with my FC. Gonna find that leak somewhere, or replace hoses, possibly the radiator as well. I drove around today, and by the end of the night, my reservoir tank was full to the top, and I saw traces of coolant on my front bumper from where the spout comes from reservoir tank.

As for the smoking, I'm suspecting the straight pipe may be the culprit. I noticed smoke coming from the the middle from under the FC, so I'm thinking there's a leak on the exhaust as well, plus most of the sound comes from that area.

Diabolical1, I've looked into CA regional forum, and found threads that are similiar to what I'm going through with smog.

Thanks again for everyone's input and advice.

 

I did a compression test earlier and noticed possibly excess oil on the front rotor leading spark plug. I remember from looking through the FAQ, that oil in the chamber is normal for the apex seals. However on the rear rotor housing, there was no oil as was on the front rotor leading spark plug. Did I find a possible/new problem or am I just worrying?