My son and I decided to get the 90 n/a GTU, It is fairly clean..... power seems ok. BUT... it smokes when first started pretty bad, as well when warm the idle surges. I believe I have read that the idle issue is the "BACV"?? but my main question is what to do with the engine. Is it better if internals are good to rebuild... or get a 2k crate motor from Mazda? Your suggestions would be most appreciated .
Thanx
Edge and kid!

Oh and one more thing... the check engine light comes on when driving and you take your foot off of the gas, the air pump and a/c compressor are off... but cats still in place.
Thanx again

 

Oil smoke on start-up means your oil seals are going bad. Does your oil smell like gas?
You'll need a rebuild to fix it. Your budget for the project and projected type of use (reliability and stability or all out power?) will determine what path you take for that engine.

You should search this forum for threads related to idle quality, there are many.

The check engine light on a 90 is the window to your computer codes, check the service manual (available online at fc3s.org if you look in their menues) for the procedure and see what your car thinks is wrong.

Welcome to the rotary community.
We have a good group of folks here in the Atlanta area that gets together almost every week so come on over!

 

Thanx CWaters... his pocketbook is very dry. Is a seal kit and doing the rebuild ourselves expensive? Or should I say hard, any "special" tools required? Would love to meet up with your group sometimes.... Is there an Atlanta chapter web site?

 

Check se-rx7.com (doesn't change much but has some good info and the email list can be found there.) and the SE section of this forum. Anything going on usually gets posted in both places.

I have the oil seal problem myself. if you're handy, I think you can rebuild it yourself. check rotary resurection (sp?) online for a good price on a rebuild (cheepest I've seen and he's in TN.) but shop around.
If you intend on racing in any form, you can get a memebership in MazdaMotorsports (Mazda's factory racer parts program) and get ~dealer pricing on most things. Check their site for the info there as well.

I should really try to do some work now...
CW

 

Hiya Edge. Congrats on your buy. It'll be more helpful for us to diagnose the problem if you provided the colour of the smoke... white/black/blue

If it's white, thats normal. Rotaries run very rich at idle. Warm idle surges are also a common problem.

Blue smoke? Not good. Some is alright because rotaries inject oil into the combustion chamber, but alot is not good. Try some Marvel Mystery oil in your oil and gas, see if that restores the seals, or cleans some of the carbon up.

Good luck

 

These engines have oil injection, so the extra consumption from worn oil control seals is not an emergency.
Do change the oil every 3K while you save up for the rebuild.
I have a copy of the manuals linked in my sig.

 

Ok white smoke is not normal, and is not from running rich either. White smoke is from coolant. Black smoke is from running rich. Blue is from oil.

 

There's quite a few of us here in Birmingham too!

 

Whooops! my bad.

 

No problemo!

 

Looks between white and blue.... I believe more of a oil issue than a coolant leak/gasket. I took it to a mechanic today and he said that running 10w-30 is bad.... 20-50 is what he suggested..... any thoughts.

Boosted....is that a pic of you in your avatar? If so, Im not sure if we should meet... your SCARY!...LOL my cell is 540-0364... call me sometime.
Edge

 

your mechanic is half-right. 10w30 is not BAD per sé, but 20w50 is reccomended.

i wouldnt worry too much about the smoke for now. But do start saving for a rebuild, and do keep an eye at the coolant/oil level. I had an issue with my 87 na's coolant jacket. Had bubbles in the coolant... exhaust gasses were pushing out all the coolant. wasn't very nice of it. took it apart... about an ounce of metal was missing where the jacket was torn apart. I kept the housing just for memories

 

20W50 is recommended, the thicker oil won't get past the seals as quickly as thinner 10W30 and will help to keep the seals from deteriorating any more. A bottle of STP "stop smoke" will actually help a LOT (this has worked for a lot of people w/ seals that are going bad). Pour one full bottle in a motor full of fresh 20W50 and drive normally for about a tank of gas (don't beat on the car too much). You will notice a lot less smoking as the thick stop smoke helps fill the worn seal. People have driven with weak seals for years, the key is to take care of the car so they don't get weaker...this stuff will help.

 

http://www.rotaryresurrection.com

Check out this site Kevin has some really good deals on rebuiding 2nd gen rotaries.A lot cheaper than buying from Mazda.And just as good.